Scientific Discipline: Atmospheric Sciences

Speaker: Kerry Emanuel

Abstract
Since the revolutionary work of Vilhelm Bjerknes, Jule Charney, and Eric Eady, geophysical fluid dynamics has dominated weather research and continues to play an important in climate dynamics. Although the physics of radiative transfer is central to understanding climate, it has played a far smaller role in weather research and is given only rudimentary attention in most educational programs in meteorology. Yet key contemporary problems in atmospheric science, such as the Madden-Julian Oscillation and the self-aggregation of moist convection, do not appear to have been solved by approaches based strictly on fluid dynamics and moist adiabatic thermodynamics. Here I will argue that many outstanding problems in meteorology and climate science involve a nontrivial coupling of circulation and radiation physics. In particular, the phenomenon of self-aggregation of moist convection depends on the interaction of radiation with time-varying water vapor and clouds, with strong implications for such diverse problems as the Madden-Julian Oscillation, tropical cyclones, and the relative insensitivity of tropical climate to radiative forcing. This argues for an augmentation of radiative transfer physics in graduate curricula in atmospheric sciences.

Scientific Discipline: Atmospheric Sciences

Speaker: Meinrat O. Andreae

Abstract
Aerosols serve as cloud condensation nuclei (CCN) and thus have a powerful effect on cloud properties. Increased aerosol concentrations resulting from pollution lead to higher cloud droplet concentrations, but smaller droplet sizes. This in turn affects the physical processes inside clouds that lead to the initiation of precipitation. Depending on a number of factors, including aerosol composition, atmospheric stability, and cloud water content, increasing CCN concentrations may either decrease or increase rainfall. In convective clouds, early rain formation is suppressed, which makes more water and energy available to rise higher in the atmosphere and form ice particles. This may invigorate the dynamics of convection, encourage the formation of hail and lightning, and enhance the transport of materials to the upper troposphere. In turn, cloud processing also affects the concentrations, composition, and distribution of atmospheric aerosols. In order to understand and quantify the effects of air pollution on climate, and precipitation in particular, knowledge of natural abundance and characteristics of aerosols is as essential as the observation of perturbed conditions. I will present recent advances in the conceptual understanding of aerosol-precipitation interactions, as well as results of measurements on aerosol and cloud characteristics in pristine and polluted conditions.

Scientific Discipline: Atmospheric Sciences

4:00 - 4:15pm PT - The Relevance of Detection and Attribution for Loss and Damage Policy
Speaker: Dáithí A Stone
Abstract: Click here for abstract

4:15pm - 4:30pm PT - The Tropical Pacific and Sub-Arctic Weather in North America
Speakers: Dennis L. Hartmann
Abstract: Click here for abstract

4:30 - 4:45pm PT - Recent Changes in Blocking Characteristics Assessed Using Self-Organizing Maps
Speakers: Jennifer Ann Francis
Abstract: Click here for abstract

4:45 - 4:55pm PT - Superensemble Climate Simulations for Attribution of 2013-15 Western U.S. Drought
Speakers: Philip Mote
Abstract: Click here for abstract

Scientific Discipline: Atmospheric Sciences

5:00 - 5:15pm PT - Providing the Larger Climate Context During Extreme Weather - Lessons from Local Television News
Speaker: Monica Woods
Abstract: Click here for abstract

5:15 - 5:30pm PT - Analysing the Response of European Ecosystems to Droughts and Heat Waves Within ISI-MIP2 Simulations
Speakers: Marie Dury
Abstract: Click here for abstract

5:30 - 5:45pm PT - Identifying Casual Effects of Climate Extremes on Societies
Speakers: Solomon M. Hsiang
Abstract: Click here for abstract

Scientific Discipline: Atmospheric Sciences

8:00 - 8:24am PT - Those Pesky Humans: Emissions and the Future of AnthroGeoscience
Speaker: Tami C. Bond
Abstract: Click here for abstract

8:24 - 8:48am PT - Dark Targets, Aerosols, Clouds and Toys
Speaker: Lorraine A. Remer
Abstract: Click here for abstract

8:48 - 9:12am PT - What Has Prevented Us from Reducing the Uncertainty in Aerosol Cloud Mediated Radiative Forcing and What Can We Do About It?
Speaker: Daniel Rosenfeld
Abstract: Click here for abstract

9:12 - 9:36am PT - The Sources, Properties, and Evolution of Organic Aerosols in the Atmosphere
Speaker: Jose L. Jimenez
Abstract: Click here for abstract

9:36 - 10:00am PT - Biogenic Organic Emissions, Air Quality and Climate
Speaker: Alex B. Guenther
Abstract: Click here for abstract

Scientific Discipline: Atmospheric Sciences

10:44 - 11:08am PT - Subtropical Circulation, Tibetan Plateau, and Asian Summer Monsoon
Speaker: Guo-Xiong Wu
Abstract: Click here for abstract

11:08 - 11:32am PT - Electromagnetic Scattering: Applications to Atmospheric Sciences and Beyond
Speaker: Ping Yang
Abstract: Click here for abstract

11:32 - 11:56am PT - Challenges in the Development of Next Generation Climate Models
Speaker: Philip J. Rasch
Abstract: Click here for abstract

11:56am - 12:20pm PT - Stratospheric Temperature Variability and Trends from Observations and Models
Speaker: William John Randel
Abstract: Click here for abstract

Scientific Discipline: Atmospheric Sciences

1:40 - 1:55pm PT - Arctoc Oscillation Cannot Be Used as Analogue to Predict the Response of Atmospheric Blocking to Arctic Amplification
Speaker: Pedram Hassanzadeh
Abstract: Click here for abstract

1:55 - 2:10pm PT - Response to Northern Hemisphere Midlatitude Circulation to Arctic Amplification in a Simple Atmospheric General Circulation Model
Speaker: Yutian Wu
Abstract: Click here for abstract

2:10 - 2:25pm PT - US CLIVAR Working Group: Arctic Change and Possible Influence on Mid-Latitude Climate and Weather
Speaker: Judah Levi Cohen
Abstract: Click here for abstract

2:25 - 2:40pm PT - Projected Changes in Regional Weather Patterns and Associated Temperature Extremes Arising from Arctic Sea Ice Loss
Speaker: James Screen
Abstract: Click here for abstract

2:40 - 2:55pm PT - Exploring the Tropically Excited Arctic Warming Mechanism with Station Data: Links Between Tropical Convection and Arctic Downward Infrared Radiation
Speaker: Steven B. Feldstein
Abstract: Click here for abstract

2:55 - 3:10pm PT - Two Distinct Influences of Arctic Warming on Cold Winters Over North America and East Asia
Speaker: Baek-Min Kim
Abstract: Click here for abstract

3:10 - 3:25pm PT - The Early Winter Sea Ice Variability Under the Recent Arctic Climate Shift
Speaker: Yang Xiao-Yi
Abstract: Click here for abstract

3:25 - 3:40pm PT - Influence of the Arctic Frontal Zone on Summer Cyclone Activity and Precipitation in the Central Arctic Ocean
Speaker: Alexander Crawford
Abstract: Click here for abstract

Scientific Discipline: Atmospheric Sciences

4:00 - 4:15pm PT - Assessments of Regional Climate Change and Land-Cover Change Impacts on Fire Weather in the United States
Speakers: Warren E. Heilman
Abstract: Click here for abstract

4:15pm - 4:30pm PT - Climate Responses to Changes in Land-Surface Properties due to Wildfires
Speakers: Yongqiang Liu
Abstract: Click here for abstract

4:30 - 4:45pm PT - Assessing the Impacts of Wildfire Aerosols on the Diurnal Cycles of Stratocumulus Clouds over Southeast Atlantic Using WRF-Chem
Speakers: Zheng Lu
Abstract: Click here for abstract

4:45 - 5:00pm PT - Increasing ENSO-Driven Drought and Wildfire Risks in a Warming Climate
Speakers: John Fasullo
Abstract: Click here for abstract

5:00 - 5:15pm PT - Development of a Region-Specific Fire Scheme in the CESM Framework
Speakers: Yufei Zou
Abstract: Click here for abstract

5:15 - 5:30pm PT - Drought and Wildfire Impacts on Carbon and Water Cycles in Terrestrial Ecosystems
Speakers: Jia Yang
Abstract: Click here for abstract

5:30 - 5:45pm PT - Trend Analysis of Carbon Monoxide Distributions for Changes in Fire vs. Anthropogenic Sources in Diverse African Regions
Speakers: Helen Worden
Abstract: Click here for abstract

5:45 - 6:00pm PT - Experiments on the Multiphase Chemistry of Isocyanic Acid, HNCO
Speakers: James M. Roberts
Abstract: Click here for abstract

Scientific Discipline: Atmospheric and Space Electricity

How Lightning Works Inside Thunderstorms: A Half-Century of Lightning Studies
Speaker: Paul R. Krehbiel

Abstract
Lightning is a fascinating and intriguing natural phenomenon, but the most interesting parts of lightning discharges are inside storms where they are obscured from view by the storm cloud. Although clouds are essentially opaque at optical frequencies, they are fully transparent at radio frequencies (RF). This, coupled with the fact that lightning produces prodigious RF emissions, has allowed us to image and study lightning inside storms using various RF and lower-frequency remote sensing techniques. As in all other scientific disciplines, the technology for conducting the studies has evolved to an incredible extent over the past 50 years. During this time, we have gone from having very little or no knowledge of how lightning operates inside storms, to being able to 'see' its detailed structure and development with an increasing degree of spatial and temporal resolution. In addition to studying the discharge processes themselves, lightning mapping observations provide valuable information on the electrical charge structure of storms, and on the mechanisms by which storms become strongly electrified.

In this presentation we briefly review highlights of previous observations, focussing primarily on the long string of remote-sensing studies I have been involved in. We begin with the study of lightning charge centers of cloud-to-ground discharges in central New Mexico in the late 1960s and continue up to the present day with interferometric and 3-dimensional time-of-arrival VHF mapping observations of lightning in normally- and anomalously electrified storms. A particularly important aspect of the investigations has been comparative studies of lightning in different climatological regimes. We conclude with observations being obtained by a high-speed broadband VHF interferometer, which show in unprecedented detail how individual lightning discharges develop inside storms. From combined interferometer and 3-D mapping data, we are beginning to unlock nature's secrets concerning mysterious, high-power discharges known as narrow bipolar events (NBEs) and, more importantly, the long-standing question of how lightning is initiated inside storms.

Abstract
AGU will present and pay tribute to the 2015 Union Prize Recipients, Awardees, Fellos and Medalists.

Scientific Discipline: Biogeosciences

Speaker: Gary King

Abstract
Carbon monoxide, which is ubiquitous on Earth, is the 2^nd most abundant molecule in the universe. Members of the domain Bacteria have long been known to oxidize it, and activities of CO oxidizers in soils have been known for several decades to contribute to tropospheric CO regulation. Nonetheless, the diversity of CO oxidizers and their evolutionary history remain largely unknown. A molybdenum-dependent dehydrogenase (Mo-CODH) couples CO oxidation by most terrestrial and marine bacteria to either O₂ or nitrate. Molybdenum dependence, the requirement for O₂ and previous phylogenetic inferences have all supported a relatively late evolution for "aerobic" CO oxidation, presumably after the Great Oxidation Event (GOE) about 2.3 Gya. Although conundrums remain, recent discoveries suggest that Mo-CODH might have evolved before the GOE, and prior to the Bacteria-Archaea split. New phylogenetic analyses incorporating sequences from extremely halophilic CO-oxidizing Euryarchaeota isolated from salterns in the Atacama Desert, brines on Hawai`i and from the Bonneville Salt Flat suggest that Mo-CODH was present in an ancestor shared by Bacteria and Archaea. This observation is consistent with results of phylogenetic histories of genes involved in Mo-cofactor synthesis, and findings by others that Mo-nitrogenase was likely active > 3 Gya. Thus, analyses of Mo-dependent CO oxidizers provide a window on the past by raising questions about the availability of Mo and non-O₂ electron acceptors. Extremely halophilic CO oxidizers also provide insights relevant for understanding the potential for extraterrestrial life. CO likely occurred at high concentrations in Mars' early atmosphere, and it occurs presently at about 800 ppm. At such high concentrations, CO represents one of the most abundant energy sources available for near-surface regolith. However, use of CO by an extant or transplanted Mars microbiota would require tolerance of low water potentials and high salt concentrations. Assays with both novel isolates and a variety of saline brines, sediments and soils show that extreme halophiles use CO in solutions of saturated NaCl (5.4 M) and at water potentials as low as -118 MPa. The latter observations are consistent with metabolic activity for conditions inferred for the recurrent slope lineae on Mars.

Scientific Discipline: Biogeosciences

8:00 - 8:15am PT - Decadal Changes in Carbon Emissions and Sinks Optimized Using a Bayesian Fusion of Multiple Observations
Speaker: Philippe Ciais
Abstract: Click here for abstract

8:15 - 8:30am PT - Changes in the Global Methane Budget Since 2000
Speaker: Philippe Bousquet
Abstract: Click here for abstract

8:30 - 8:45am PT - The Full Budget of Greenhouse Gases in the Terrestrial Biosphere: From Global C Project to Global GHG Project
Speaker: Hanqin Tian
Abstract: Click here for abstract

8:45 - 9:00am PT - A New Data Product: Gridden Uncertainty Maps of Fossil Fuel Carbon Dioxide Emissions
Speaker: Robert J. Andres
Abstract: Click here for abstract

9:00 - 9:15am PT - Climate Constraints on the Carbon Intensity of Economic Growth
Speaker: Steven J. Davis
Abstract: Click here for abstract

9:15 - 9:30am PT - The Dominant Role of Semi-Arid Lands in the Trend and Variability of the Land CO₂ sink
Speaker: Anders Ahlström
Abstract: Click here for abstract

9:30 - 9:45am PT - Nitrogen Dynamics are a Key Factor in Explaining Global Land Carbon Sink
Speaker: Deborah N. Huntzinger
Abstract: Click here for abstract

9:45 - 10:00am PT - Changes in Terrestrial CO₂ Budget in Siberia in the Past Three Decades
Speaker: Kazuhito Ichii
Abstract: Click here for abstract

Scientific Discipline: Cryosphere

8:00 - 8:15am PT - Black Carbon and Other Light-Absorbing Impurities in the Andes of Northern Chile
Speaker: Penny M. Rowe
Abstract: Click here for abstract

8:15 - 8:30am PT - Dust, Elemental Carbon and Other Impurities on Central Asian Glaciers: Origin and Radiative Forcing
Speaker: Julia Schmale
Abstract: Click here for abstract

8:30 - 8:45am PT - Factors Controlling Black Carbon Deposition in Snow in the Arctic
Speaker: Ling Qi
Abstract: Click here for abstract

8:45 - 9:00am PT - Hydrological Response to Black Carbon Deposition in Seasonally Low Snow Covered Catchments in Norway Using Two Different Atmospheric Transport Models
Speaker: Felix Matt
Abstract: Click here for abstract

9:00 - 9:15am PT - Hydrologic Impacts of Land Cover Disturbances in the Upper Colorado River Basin
Speaker: Ben Livneh
Abstract: Click here for abstract

9:15 - 9:30am PT - A Review of Measurement and Modeling of Light-Absorbing Particles in Snow and Ice and Their Climatic and Hydrological Impact
Speaker: Yun Qian
Abstract: Click here for abstract

9:30 - 9:45am PT - Antarctic Black Carbon Tracks Southern Hemisphere Climate Throughout the Holocene
Speaker: Monica M. Arienzo
Abstract: Click here for abstract

9:45 - 10:00am PT - Fire Impacts on the Cryosphere
Speaker: Natalie M. Kehrwald
Abstract: Click here for abstract

Scientific Discipline: Cryosphere

Ice Sheet Systems and Sea Level Change
Speaker: Eric J. Rignot

Abstract
Modern views of ice sheets provided by satellites, airborne surveys, in situ data and paleoclimate records while transformative of glaciology have not fundamentally changed concerns about ice sheet stability and collapse that emerged in the 1970's. Motivated by the desire to learn more about ice sheets using new technologies, we stumbled on an unexplored field of science and witnessed surprising changes before realizing that most were coming too fast, soon and large. Ice sheets are integrant part of the Earth system; they interact vigorously with the atmosphere and the oceans, yet most of this interaction is not part of current global climate models. Since we have never witnessed the collapse of a marine ice sheet, observations and exploration remain critical sentinels. At present, these observations suggest that Antarctica and Greenland have been launched into a path of multi-meter sea level rise caused by rapid climate warming. While the current loss of ice sheet mass to the ocean remains a trickle, every mm of sea level change will take centuries of climate reversal to get back, several major marine-terminating sectors have been pushed out of equilibrium, and ice shelves are irremediably being lost. As glaciers retreat from their salty, warm, oceanic margins, they will melt away and retreat slower, but concerns remain about sea level change from vastly marine-based sectors: 2-m sea level equivalent in Greenland and 23-m in Antarctica. Significant changes affect 2/4 marine-based sectors in Greenland - Jakobshavn Isb. and the northeast stream - with Petermann Gl. not far behind. Major changes have affected the Amundsen Sea sector of West Antarctica since the 1980s. Smaller yet significant changes affect the marine-based Wilkes Land sector of East Antarctica, a reminder that not all marine-based ice is in West Antarctica. Major advances in reducing uncertainties in sea level projections will require massive, interdisciplinary efforts that are not currently in place but are getting there. Projection scenarios are overwhelmingly conservative, pushed up by observations, awaiting more detailed knowledge of ocean circulation, winds, ice-ocean interaction, and mechanics of rapid ice fracture, not to mention the mere definition of static boundaries (ice thickness and sea floor bathymetry).

Scientific Discipline: Cryosphere

1:40 - 1:55pm PT - Investigating the Greenland Firn Aquifer Near Helheim Glacier Based on Geophysical Noninvasive Methods and in Situ Measurements
Speaker: Clément Miège
Abstract: Click here for abstract

1:55 - 2:10pm PT - Supraglacial Fluvial Landscape Evolution on the Greenland Ice Sheet
Speaker: Leif Karlstrom
Abstract: Click here for abstract

2:10 - 2:25pm PT - Greenland Englacial Drainage: Conditions Favoring Water Transport Through a Fractured Aquifer
Speaker: Timothy T. Creyts
Abstract: Click here for abstract

2:25 - 2:40pm PT - Water Levels in Crevasses Reveal Subglacial Water Pressure Variations at Helheim Glacier, South East Greenland
Speaker: Alistair Everett
Abstract: Click here for abstract

2:40 - 2:55pm PT - Effects of Isolated Drainage on the Seasonal Evolution of the Greenland Subglacial Hydrologic System
Speaker: Matthew J. Hoffman
Abstract: Click here for abstract

2:55 - 3:10pm PT - The Role of Meltwater Variability in Modulating Diurnal to Inter-Annual Ice-Sheet Flow: New Insights From a ~Decade of High-Temporal Resolution GPS Observations on the Western Greenland Margin
Speaker: Laura A. Stevens
Abstract: Click here for abstract

3:10 - 3:25pm PT - Patterns of Rapid Deceleration Observed at Two Tidewater Outlet Glaciers in West Greenland
Speaker: Leigh A. Stearns
Abstract: Click here for abstract

3:25 - 3:40pm PT - Seasonal Ice Flow Patterns as Indicators of Subglacial Hydrology on the Greenland Ice Sheet
Speaker: Twila A. Moon
Abstract: Click here for abstract

Scientific Discipline: Education

1:40 - 1:55pm PT - Introductory Remarks on the Intersection of Climate Literacy and Misconceptions

1:55 - 2:10pm PT - Reasons and Resources for Being Explicit About the Practices of Science
Speaker: Anne E. Egger
Abstract: Click here for abstract

2:10 - 2:25pm PT - The World Climate Exercise: Is (Simulated) Experience Our Best Teacher?
Speaker: Kenneth Rath
Abstract: Click here for abstract

2:25 - 2:40pm PT - Barrier Busting: Leapfrogging Zombie Science Arguments to Get to Solutions
Speaker: Susan Joy Hassol
Abstract: Click here for abstract

2:40 - 2:55pm PT - Motivated Rejection of (Climate) Science: Causes, Tools, and Effects
Speaker: Stephan Lewandowsky
Abstract: Click here for abstract

2:55 - 3:10pm PT - Who Trusts Scientists for Information About Climate Change? Nuclear Power? Vaccines?
Speaker: Lawrence Hamilton
Abstract: Click here for abstract

3:10 - 3:25pm PT - Measuring Engagement with the Potential Consequences of Climate Change
Speaker: Neil Young
Abstract: Click here for abstract

3:25 - 3:40pm PT - Student Leadership and Climate Literacy
Speaker: Jessica Lura
Abstract: Click here for abstract

Scientific Discipline: Earth and Planetary Surface Processes

Variability Matters: New Insights into Mechanics of River Avulsions on Deltas and Their Deposits
Speaker: Vamsi Ganti

Abstract
River deltas are highly dynamic, often fan-shaped depositional systems that form when rivers drain into a standing body of water. They host over a half billion people and are currently under threat of drowning and destruction by relative sea-level rise, subsidence, and anthropogenic interference. Deltas often develop planform fan shapes through avulsions, whereby major river channel shifts occur via “channel jumping” about a spatial node, thus determining their fundamental length scale. Emerging theories suggest that the size of delta lobes is set by backwater hydrodynamics; however, these ideas are difficult to test on natural deltas, which evolve on centennial to millennial timescales. In this presentation, I will show results from the first laboratory delta built through successive deposition of lobes that maintain a constant size that scales with backwater hydrodynamics. The characteristic size of deltas emerges because of a preferential avulsion node that remains fixed spatially relative to the prograding shoreline, and is a consequence of multiple river floods that produce persistent morphodynamic river-bed adjustment within the backwater zone. Moreover, river floods cause erosion in the lowermost reaches of the alluvial river near their coastline, which may leave erosional boundaries in the sedimentary record that may appear similar to those previously interpreted to be a result of relative sea-level fall. I will discuss the implications of these findings in the context of sustainability management of deltas, decoding their stratigraphic record, and identifying ancient standing bodies of water on other planets such as Mars. Finally, I will place this delta study in a broader context of recent work that highlights the importance of understanding and quantifying variability in sedimentology and geomorphology.

Scientific Discipline: Geodesy

5:00 - 5:05pm PT - Award Presentation

5:05 - 5:10pm PT - Introductory Remarks

5:10 - 5:50pm PT - Turtles to TerabytesL The Ongoing Revolution in Volcano Geodesy
Speaker: Daniel Dzurisin
Abstract: Click here for abstract

5:50 - 6:00pm PT - Discussion

Scientific Discipline: Global Environmental Change

10:20 - 10:25am PT - Special Assessment Reports: A Critical Part of the Sustained National Climate Assessment Process
Speaker: Glynis C. Lough
Abstract: Click here for abstract

10:25 - 10:30am PT - Assessing and Synthesizing the Last Decade of Research on the Major Pools and Fluxes of the Carbon Cycle in the U.S. and North America: An Interagency Governmental Perspective
Speakers: Nancy Cavallaro
Abstract: Click here for abstract

10:30 - 10:40am PT - The State of the Carbon Cycle: Ten Years On
Speakers: Anthony W. King
Abstract: Click here for abstract

10:40 - 10:50am PT - If the North American Carbon Cycle Was Changing, Would We Notice?
Speakers: Kenneth J. Davis
Abstract: Click here for abstract

10:50 - 11:00am PT - Inventory of U.S. Greenhouse Gas Emissions and Sinks: an Overview of Planned Improvements to the Methodologies and Activity Data Used to Develop the Carbon Estimates in the Land Use, Land-Use Change, and Forestry (LULUCF) Sector
Speakers: Thomas Charles Wirth
Abstract: Click here for abstract

11:00 - 11:10am PT - The Loss of Late Successional Species Has a Disproportionate Impact on Terrestrial Carbon Storage in North America
Speakers: David J. Moore
Abstract: Click here for abstract

11:10 - 11:20am PT - The Contribution of Soils to North America's Current and Future Climate
Speakers: Melanie A. Mayes
Abstract: Click here for abstract

11:20 - 11:30am PT - The Alaska Land Carbon Assessment: Baseline and Projected Future Carbon Storage and Greenhouse Gas Fluxes in Ecosystems in Alaska
Speakers: Anthony David McGuire
Abstract: Click here for abstract

11:30 - 11:40am PT - What Have We Learned About Arctic Carbon Since the First State of the Carbon Cycle Report?
Speakers: Edward Schuur
Abstract: Click here for abstract

11:40 - 11:50am PT - Aquatic Carbon Fluxes from the Conterminous U.S. and Alaska
Speakers: David E. Butman
Abstract: Click here for abstract

11:50am - 12:00pm PT - The Carbon Budget of Coastal Waters of Eastern North America
Speakers: Raymond Najjar
Abstract: Click here for abstract

12:00 - 12:10pm PT - Advances on Interdisciplinary Approaches to Urban Carbon
Speakers: Patricia Romero-Lankao
Abstract: Click here for abstract

12:10 - 12:20pm PT - Urbanizing and the Carbon Cycle: Synthesis of Ongoing Research
Speakers: Kevin R. Gurney
Abstract: Click here for abstract

Scientific Discipline: Global Environmental Change

8:00 - 8:10am PT - Introductory Remarks
Speaker: Max Auffhammer

8:10 - 8:28am PT - A Reassessment of 20th Century Global Sea-Level Change
Speaker: Carling Hay
Abstract: Click here for abstract

8:28 - 8:42am PT - Disruption of the European Climate Seasonal Clock in a Warming World
Speaker: Julien Cattiaux
Abstract: Click here for abstract

8:42 - 8:56am PT - Changes of Climate Regimes During the Last Millennium and the Twenty-First Century as Simulated by the Community Earth System Model
Speaker: Song Feng
Abstract: Click here for abstract

8:56 - 9:14am PT - Detecting and Quantifying the Anthropogenic Influence on Extremes
Speaker: Francis W. Zwiers
Abstract: Click here for abstract

9:14 - 9:28am PT - Attributing Human Mortality During Extreme Heat Waves to Anthropogenic Climate Change
Speaker: Dann Mitchell
Abstract: Click here for abstract

9:28 - 9:46am PT - Advances and Challenges in the Attribution of Climate Impacts Using Statistical Inference
Speaker: Solomon M. Hsiang
Abstract: Click here for abstract

9:46 - 10:00am PT - Quantifying Loss and Damage from Anthropogenic Climate Change - Briding the Gap Between Two Research Communities
Speaker: Friederike Elly Luise Otto
Abstract: Click here for abstract

Scientific Discipline: Global Environmental Change

4:00 - 4:20pm PT - Robust Engineering Designs for Infrastructure Adaptation to a Changing Climate
Speaker: Constantine Samaras
Abstract: Click here for abstract

4:20 - 4:40pm PT - Understanding the Uncertainties in Consequences of Climate Change for the United States Power Sector Infrastructure When Considering a Realistic Mitigation Pace and Adaptation Needs
Speakers: Ines Azevedo
Abstract: Click here for abstract

4:40 - 5:00pm PT - Learning and Risk Exposure in a Changing Climate
Speakers: Frances Moore
Abstract: Click here for abstract

5:00 - 5:11pm PT - Engaging a Moving Target: Adapting to Rates of Climate Change
Speakers: Soheil Shayegh
Abstract: Click here for abstract

5:11 - 5:22pm PT - Regional Heterogeneity in the Rates of Warming from CO2 Emissions
Speakers: Kate Ricke
Abstract: Click here for abstract

5:22 - 5:33pm PT - Investigating the Pace of Temperature Change and Its Implications Over the Twenty-First Century
Speakers: Yann Chavaillaz
Abstract: Click here for abstract

5:33 - 5:44pm PT - Rate and Velocity of Climate Change Caused by Cumulative Carbon Emissions
Speakers: Steven J. Davis
Abstract: Click here for abstract

5:44 - 6:00pm PT - Ultrarapid Poster Presentations
Speakers: Ken Caldeira
Abstract: Click here for abstract

Scientific Discipline: Global Environmental Change

10:20 - 10:35am PT - Coral Reef Color: Remote and In-Situ Imaging Spectroscopy of Reef Structure and Function
Speaker: Eric J. Hochberg
Abstract: Click here for abstract

10:35 - 10:50am PT - Multiyear Multiseasonal Changes in Leaf and Canopy Traits Measured by AVIRIS Over Ecosystems with Different Functional Type Characteristics Through the Progressive California Drought 2013-2015
Speakers: Susan Ustin
Abstract: Click here for abstract

10:50 - 11:05am PT - Assessment of Forest Vulnerability to Climate Change from Imaging Spectroscopy
Speakers: Gregory Paul Asner
Abstract: Click here for abstract

11:05 - 11:20am PT - Overview of the Technical and Scientific Status of the EnMAP Imaging Spectroscopy Mission
Speakers: Luis Guanter
Abstract: Click here for abstract

11;20 - 11:35am PT - Monitoring the Impacts of Severe Drought on Plant Species in Southern California Chaparral
Speakers: Philip E. Dennison
Abstract: Click here for abstract

11:35 - 11:50am PT - HyspIRI Measurements of Agricultural Systems in California: 2013-2015
Speakers: Philip A. Townsend
Abstract: Click here for abstract

11:50am - 12:05pm PT - Advances in Mineral Dust Source Composition Measurement with Imaging Spectroscopy at the Salton Sea, CA
Speakers: Robert O. Green
Abstract: Click here for abstract

12:05 - 12:20pm PT - Mapping Land Surface Energy Budget from the AVIRIS and MASTER Data
Speakers: Shunlin Liang
Abstract: Click here for abstract

Scientific Discipline: Global Environmental Change

1:40 - 1:45pm PT - Introductory Remarks

1:45 - 2:40pm PT - Extreme Weather ina  Changing Climate
Speaker: Donald J. Wuebbles

Abstract
It is a real honor for me to get the opportunity to pay homage to Steve Schneider and his extensive accomplishments. I also treasured his friendship. Steve was known for being a great communicator and for his expertise in climate policy and solutions, along with being an outstanding scientist with many contributions to understanding the Earth’s climate system. One of the major challenges today to all of these areas is the changing trends in extreme weather under a changing climate. My focus in this presentation is to examine these issues by drawing on new research from my own team at Illinois. For example, climate change amplification in the Arctic has raised questions regarding its potential effects on extreme weather at mid-latitudes, especially the United States. In our studies, we find a statistically significant relationship between summer sea ice north of Alaska and geopotential height anomalies in the north Pacific during subsequent winter and spring months. The frequency of these semi-persistent height anomalies exhibits a long-term upward trend that amplify the jet stream off the West Coast of the U.S., driving more persistent precipitation patterns over certain regions of the United States, specifically in the West and Midwest parts of the country. Our results suggest that as sea ice in the Arctic north of Alaska continues to decrease, a more persistent ridge will form in areas adjacent to this location and affect storm tracks over the continental United States. In other studies, we are examining the effects of the changing climate on trends in extreme events throughout the continental U.S. We are also investigating changes in historical severe convective weather over the United States using reanalysis data, the NEXRAD/in situ gauge Climate Data Record (CDR) data set, and storm reports. After analyzing the ability of global climate models to represent the observed trends in severe-thunderstorm environments, projected future trends are also to be analyzed.

Scientific Discipline: Global Environmental Change

2:40 - 2:45pm PT - Introductory Remarks

2:45 - 3:40 PT - Thin Ice -- Bipolar Super Interglacials and Our Possible Future
Speaker: Julie Brigham-Grette

Abstract
Evidence of exceptionally warm Arctic interglacials from Lake El’gygytgyn NE Russia, combined with the periodic collapse of the West Antarctic Ice Sheet (ANDRILL) suggests the need to reassess climate sensitivity and cryospheric dynamics on many timescales. It may be easier to melt significant portions of large sheets and drive large ecosystem changes in the high latitudes than we thought! Elevated global temperatures of only a few degrees (or less) combined with polar amplification seems to have repeatedly caused large changes in the cryosphere and global sea level, still under investigation given the present knowledge and complexity of glacio-isostatic adjustments. But increasing evidence of a forested Arctic and smaller polar ice sheets in the Pliocene when CO₂ was around 400 ppm (like today) and during several more recent super interglacials (under Milankovitch forcing) most likely presages a warming future, partially hidden in recent years by the lagged response of the oceans, atmosphere, and cryosphere to anthropogenic influences. The future will depend on the ability of societies to recognize and respond to the consequences of significant environmental change. The challenge to the science community is to communicate this data-driven reality effectively and without politics.

Scientific Discipline: Global Environmental Change

8:00 - 8:15am PT - Satellite Observations of Groundwater Storage Variations and Their Application for Water Security Monitoring
Speaker: Matthew Rodell
Abstract: Click here for abstract

8:15 - 8:30am PT - Advances in Remote Sensing for Vegetation Dynamics and Agricultural Management
Speaker: Compton J. Tucker
Abstract: Click here for abstract

8:30 - 8:45am PT - Water Dependency and Water Exploitation at Global Scale as Indicators of Water Security
Speaker: A.P.J. De Roo
Abstract: Click here for abstract

8:45 - 9:00am PT - Assessment of Global Water Security: Moving Beyond Water Scarcity Assessment
Speaker: Yoshihide Wada
Abstract: Click here for abstract

9:00 - 9:15am PT - An Integrated Water-Energy-Food-Livelihoods Approach for Assessing Environmental Livelihood Security
Speaker: Eloise M. Biggs
Abstract: Click here for abstract

9:15 - 9:30am PT - Toward the Nexus Equation: A Conceptual and Mathematical Framework for Energy-Water-Food Nexus Analysis
Speaker: Chad W. Higgins
Abstract: Click here for abstract

9:30 - 9:45am PT - Designing Multi-Reservoir System Designs via Efficient Water-Energy-Food Nexus Trade-Offs -- Selecting New Hydropwer Dams for the Blue Nile and Nepal's Koshi Basin
Speaker: Julien J. Harou
Abstract: Click here for abstract

9:45 - 10:00am PT - Contrasting Rainfall Declines in Northern and Southern Tanzania: Potential Differential Impacts of West Pacific Warming and East Pacific Cooling
Speaker: Laura Harrison
Abstract: Click here for abstract

Scientific Discipline: Global Environmental Change

1:40 - 1:55pm PT - Multi-Decadal to Millennial-Scale Reconstructions of Global Biomass Burning and its Responses to Changes in Climate, Vegetation and Anthropogenic Forcings
Speaker: Jennifer R. Marlon
Abstract: Click here for abstract

1:55 - 2:10pm PT - What Fraction of Global Fire Activity Can Be Forecast Using Sea Surface Temperatures?
Speaker: Yang Chen
Abstract: Click here for abstract

2:10 - 2:25pm PT - Fire in Earth System Models
Speaker: Silvia Kloster
Abstract: Click here for abstract

2:25 - 2:40pm PT - Wild?res in a Warmer Climate: Emission Fluxes, Emission Heights and Black Carbon Concentrations in 2090-2099
Speaker: Silvia Kloster
Abstract: Click here for abstract

2:40 - 2:55pm PT - Introducing the Global Fire WEather Database (GFWED)
Speaker: Robert D. Field
Abstract: Click here for abstract

2:55 - 3:10pm PT - Fire, Lava Flows, and Human Evolution
Speaker: Michael Johns Medler
Abstract: Click here for abstract

3:10 - 3:25pm PT - Evaluation of a Chemical Proxy for Fire Intensity: A Potential Tool for Studying Fire-Climate Feedbacks
Speaker: William C. Hockaday
Abstract: Click here for abstract

3:25 - 3:40pm PT - Vulnerability and Resilience of Temperate Forest Landscapes to Broad-Scale Deforestation in Response to Changing Fire Regimes and Altered Post-Fire Vegetation Dynamics
Speaker: Alan J. Tepley
Abstract: Click here for abstract

Scientific Discipline: Geomagnetism and Paleomagnetism

Water and Electricty Do Mix: Studying Plates, Petroleum, and Permafrost Using Marine Electromagnetism
Speaker: Steven Constable

Abstract
Marine magnetotelluric (MT) and controlled-source electromagnetic (CSEM) sounding methods were developed in the early 1980's as deep-water academic tools to study the oceanic lithosphere and mantle. Electrical conductivity is a strong function of porosity, temperature, melting, and volatile content, and so marine MT and CSEM data can be used to address a variety of geological questions related to plate tectonics. These include the distribution of melt at mid-ocean ridges, the fate of fluids in subduction zones, and the nature of the lithosphere-asthenosphere boundary. With the advent of deepwater oil and gas drilling in the late 1990's, marine EM methods were embraced by the exploration community, and are now routinely used to assist in exploration and make drilling decisions for wells costing $100M or more. For countries without conventional hydrocarbon resources, gas hydrate offers the potential for energy production, and marine CSEM methods may be the only effective way to explore for and characterize this resource. The use of EM methods to map geothermal, groundwater, and mineral resources also has application in the marine environment. Water and electricity has proved to be a very successful mix!

Scientific Discipline: Hydrology

8:00 - 8:15am PT - Causes of the 2011-15 California Drought
Speaker: Richard Seager
Abstract: Click here for abstract

8:15 - 8:30am PT - California's Epic 21st Century Drought - Where Are We At and Where Do We Go From Here?
Speakers: Michael Anderson
Abstract: Click here for abstract

8:30 - 8:45am PT - Contribution of Anthropogenic Warning to California Drought During 2012-2015
Speakers: Park Williams
Abstract: Click here for abstract

8:45 - 9:00am PT - The Role of Internal Variability in Prolonging the California Drought
Speakers: Nikolaus H. Buenning
Abstract: Click here for abstract

9:00 - 9:15am PT - How Has Human-Induced Climate Change Affected California Drought Risk?
Speakers: Linyin Cheng
Abstract: Click here for abstract

9:15 - 9:30am PT - Contribution of Temperature and Precipitation Anomalies to the Ongoing California Drought
Speakers: Lifeng Luo
Abstract: Click here for abstract

9:30 - 9:45am PT - Interated Modeling of Drought-Impacted Areas Using Remote Sensing and Microenvironmental Data in California
Speakers: Mahesh Rao
Abstract: Click here for abstract

9:45 - 10:00am PT - Use of Sequent Peak Algorithm Drought Severity Index and Hydroclimatic Reconstructions from Tree-Rings to Inform Water Supply Reliability Planning
Speakers: Ben S. Bray
Abstract: Click here for abstract

Scientific Discipline: Hydrology

10:20 - 10:35am PT - The Physics of Great Plains Drought, Its Predictability, and Its Changed Risk in a Warming World
Speaker: Martin P. Hoerling
Abstract: Click here for abstract

10:35 - 10:50am PT - Why Different Drought Indexes Show Distinct Future Drought Risk Outcomes in the U.S. Great Plains?
Speakers: Song Feng
Abstract: Click here for abstract

10:50 - 11:05am PT - Warm Season Drought Development Over North America and Northern Eurasia: The Rold of Stationary Rossby Waves
Speakers: Hailan Wang
Abstract: Click here for abstract

11:05 - 11:20am PT - Evaluating the Potential Use for Remotely Sensed Soil Moisture Data for Agricultural Drought Risk Monitoring
Speakers: Hongxiang Yan
Abstract: Click here for abstract

11:20 - 11:35am PT - Propagation of Model and Forcing Uncertainty Into Hydrological Drought Characteristics in a Multi-Model Century-Long Experiment in Continental River Basins
Speakers: Luis E. Samaniego
Abstract: Click here for abstract

11:35 - 11:50am PT - Probabilistic Assessment of Meteorological Drought Risk Over the Canadian Prairie Provinces Based on the NARCCAP Multi-RCM Ensemble
Speakers: Mohammad Badrul Masud
Abstract: Click here for abstract

11:50am - 12:05pm PT - Comparison of Bootstrapping and Markov Chain Monte Carlo for Copula Analysis of Hydrological Droughts
Speakers: Pan Yang
Abstract: Click here for abstract

Scientific Discipline: Hydrology

Speaker: Tissa H. Illangasekare

Abstract
Problems of water sustainability to meet the increasing needs of a growing world population, further exacerbated by climate change, will continually challenge hydrologists and other earth and environmental scientists. Significant theoretical, modeling, and computational advances, and technology developments for improved observations, monitoring, and characterization that have taken place during the last several decades have helped to meet some of these challenges. In parallel, field and laboratory studies for conceptualization, hypothesis testing, and model improvements have continued to advance hydrologic sciences. However, the data to study some of the problems in hydrology cannot always be obtained from field studies where many factors contribute to the uncertainty of measurements and parameter estimates. The primary thesis of this talk is that laboratory experiments conducted at multiple test scales will play an important role by providing new insights into complex processes and accurate data for model improvement, leading to increased accuracy and reliability of predictions. However, performing such controlled experiments poses many challenges such as acquiring data at different observational scales, capturing relevant features of geologic heterogeneity, mimicking field specific pressure and temperature dependent phase interactions in the laboratory, and simulating climate drivers, among others. Focusing on the subsurface and using examples from multiphase systems, coastal aquifer salinization, and land/atmospheric interactions, I will show how to design and implement theory-driven experiments to address some of these challenges. I will make the case that addressing problems in hydrology requires continuous interaction among laboratory and field studies and modeling. It is imperative that hydrologists work at the disciplinary interfaces related to earth, water, energy, and the environment to address current and emerging problems that are of global importance.

Scientific Discipline: Hydrology

1:40 - 1:55pm PT - Vulnerability and Risk Assessment for the Management of Changing Water Resources
Speaker: Howard S. Wheater
Abstract: Click here for abstract

1:55 - 2:10pm PT - Climate and Humans as Amplifiers of Hydro-Ecologic Change: Science and Policy Implications for Intensively Managed Landscapes
Speaker: Efi Foufoula-Georgiou
Abstract: Click here for abstract

2:10 - 2:25pm PT - A New Global Metric of Water Scarcity Accounting for the Role of Storage
Speaker: Jim W. Hall
Abstract: Click here for abstract

2:25 - 2:40pm PT - Crop Insurance Increases Water Withdrawals for Irrigation in Agriculture
Speaker: Megan Konar
Abstract: Click here for abstract

2:40 - 2:55pm PT - Scientific Insights for Managing Droughts in California
Speaker: Jay R. Lund
Abstract: Click here for abstract

2:55 - 3:10pm PT - A Screening-Level Approach for Comparing Risks Affecting Aquatic Ecosystem Services Over Socio-Environmental Gradients
Speaker: Thomas C. Harmon
Abstract: Click here for abstract

3:10 - 3:25pm PT - Windows of Opportunity for Groundwater Management
Speaker: Timothy Foster
Abstract: Click here for abstract

3:25 - 3:40pm PT - Modeling and Managing Urban Water Demand Through Smart Meters: Benefits and Challenges from Current Research and Emerging Trends
Speaker: Andrea Cominola
Abstract: Click here for abstract

Scientific Discipline: Hydrology

4:00 - 4:15pm PT - A National Assessment of the Potential Impacts of Hydraulic Fracturing Activities on Drinking Water Resources
Speaker: Caroline Ridley
Abstract: Click here for abstract

4:15 - 4:30pm PT - Groundwater Monitoring of Hydraulic Fracturing in California: Recommendations for Permit-Required Monitoring
Speaker: Bradley K. Esser
Abstract: Click here for abstract

4:30 - 4:45pm PT - Assessment of the Impacts of Hydraulic Fracturing at Bakken on Regional Water Resources
Speaker: Zhulu Lin
Abstract: Click here for abstract

4:45 - 5:00pm PT - Impacts on Water Quality by Hydraulic Fracturing in Pennsylvania
Speaker: Beizhan Yan
Abstract: Click here for abstract

5:00 - 5:15pm PT - Investigating the Hydro-Geochemical Impact of Fugitive Methane on Groundwater: The Borden Aquifer Controlled Release Study
Speaker: Aaron Graham Cahill
Abstract: Click here for abstract

5:15 - 5:30pm PT - Identifying the Sources of Methane in Shallow Groundwaters in Parker and Hood Counties, Texas Through Noble Gas Signatures
Speaker: Tao Wen
Abstract: Click here for abstract

5:30 - 5:45pm PT - Identifying Sources, Formation Pathways and Geological Controls of Methane in Shallow Groundwater Above Unconventional Natural Gas Plays in Alberta, Canada
Speaker: Bernhard Mayer
Abstract: Click here for abstract

5:45 - 6:00pm PT - Assessing Radium Activity in Shale Gas Produced Brine
Speaker: Wenjia Fan
Abstract: Click here for abstract

Scientific Discipline: Earth and Space Science Informatics

Toward a Digital Resilience (with a Dash of Location Enlightenment)
Speaker: Dawn J. Wright

Abstract
The AGU Earth and Space Science Informatics Focus Group addresses a compelling array of research questions and projects. This year’s session topics range from large-scale data management within global cyberinfrastructures or virtual observatories, to intelligent systems theory, semantics, and handling of near-real-time data streams, to issues of “dark data,” data transparency, reproducibility, and more. The aim of this lecture is to build in part on these themes but to consider more broadly how we might push the boundaries of informatics knowledge more along the lines of use-inspired science (responsive to the needs and perspectives of society while still being fundamental and cutting edge). To wit, as we contend with human impacts on the biosphere recent innovations in computational and data science are now facilitating community resilience to climate change (e.g., helping communities to monitoring air quality or drought, find available drinking water, determine habitat vulnerability, etc.). But not often discussed is a path toward digital resilience. If digital tools are to continue helping communities, it stands to reason that they must engender some resilience themselves. The capacity to deal effectively with change and threats, to recover quickly from challenges or difficulties, even to withstand stress and catastrophe, can apply to data too. As investments in digital data continue to rise, we find ourselves in new “digital world order” comprised of ubiquitous technologies from satellites to wristwatches to human biochip implants. And a significant proportion of these are geospatial, given the incredible power of maps to communicate, persuade, inspire, understand, and elicit action. Therefore, the lecture reviews and recommends seven fundamental digital research and communication practices. The aim is ensuring not only a modicum of resilience for our nascent discipline, but in prototyping and delivering repeatable solutions that all can use to help guide the planet towards a more resilient future.

Scientific Discipline: Nonlinear Geophysics

10:20 - 10:35am PT - Statistical Analysis of Seismicity Associated with Hydraulic Fracturing in Western Canada
Speaker: Robert Shcherbakov
Abstract: Click here for abstract

10:35 - 10:50am PT - Facies Analysis and b-Value for Operationally Induced Microseismicity
Speakers: David W.S. Eaton
Abstract: Click here for abstract

10:50 - 11:05am PT - Hydraulic Fracturing of 403 Shallow Diatomite Wells in South Belridge Oil Field, Kern County, California, in 2014
Speakers: Dan B. Wynne
Abstract: Click here for abstract

11:05 - 11:20am PT - Fully Coupled 3D Finite Element Model of Hydraulic Fracturing in a Permeable Rock Formation
Speakers: Saeed Salimzadeh
Abstract: Click here for abstract

11:20 - 11:35am PT - Measurement of Three Dimensional Strains Surrounding Hydraulic Fracture in Brittle Hydrogel
Speakers: Will Steinhardt
Abstract: Click here for abstract

11:35 - 11:50am PT - Are Earthquakes Predictable? A Study on Magnitude Correlations in Earthquake Catalog and Experimental Data
Speakers: Katerina Stavrianaki
Abstract: Click here for abstract

11:50am - 12:05pm PT - Spatial Verification of Earthquake Simulators Using Self-Consistent Metrics for Off-Fault Seismicity
Speakers: John Max Wilson
Abstract: Click here for abstract

12:05 - 12:20pm PT - Phase Transitions in Geomorphology
Speakers: Carlos Pompeyo Ortiz
Abstract: Click here for abstract

Scientific Discipline: Nonlinear Geophysics

1:40 - 1:50pm PT - Introductory Remarks

1:50 - 2:30pm PT - Why the Warming Can't Be Natural: the Nonlinear Geophysics of Climate Closure
Speaker: Shaun Lovejoy
Abstract: Click here for abstract

2:30 - 2:40pm PT - Discussion

Scientific Discipline: Natural Hazards

Speaker: Susan Cutter

Abstract
When geographer Gilbert F. White founded the Natural Hazards Center at the University of Colorado in 1975, he was adamant that the knowledge amassed by the research community be available to practitioners. Recognizing that it does not take an extreme event to produce extreme consequences, White argued for an equal emphasis on technologically-oriented solutions to natural hazards problems, alongside the social, economic, and political factors that lead to the non-adoption of the technological solutions, and then the translation of these findings into useful practices. In later writings (2001) he commented on the paradox of modern society in not achieving this balance suggesting that while we have more knowledge and abilities to manipulate nature, simultaneously we have increased our exposure and susceptibility to natural hazards through our own actions and development patterns.

This paper reviews the need for, status of, and role of integrated research on disaster risk in policy and practice. The reduction in economic and human loss requires such integrated knowledge on disaster risk, evidence-based policy appraisals, and more progressive approaches to hazards and disaster risk management. This means a re-framing of current programs and policies away from response to a more pro-active and longer term emphases on enhancing resilience at local to global scales. Linking hazards science and practice to larger societal and development objectives is the path toward a more resilient future, a goal that personifies the scholarship of Gilbert F. White.

Scientific Discipline: Ocean Sciences

9:00 - 9:10am PT - Introductory Remarks

9:10 - 9:55am PT - Exploring Frontiers of the Deep Biosphere Through Scientific Ocean Drilling
Speakers: Fumio Inagaki
Abstract: Click here for abstract

9:55 - 10:00am PT - Discussion

Scientific Discipline: Ocean Sciences

1:40 - 1:50pm PT - Introductory Remarks

1:50 - 2:40pm PT - The Subpolar North Atlantic Spring Bloom - What Did We Learn from the NAB 2008 Autonomous Experiment?
Speaker: Mary Jane Perry

Abstract
The subpolar North Atlantic bloom is one of the most remarkable features on the planet, with almost explosive ‘greening’ of the oceans. Over decades, investigators from countries bordering the North Atlantic have caught snippets of the bloom from research vessels or merchant ships transiting between continents. On 4 April 2008, Eric D’Asaro, Craig Lee, and I began a comprehensive study of the initiation and demise of the spring bloom using 2 types of autonomous platforms – a patch-following Lagrangian mixed-layer float and 4 float-following gliders. The 3 mo autonomous experiment integrated measurements from the float, gliders and ships, observations from satellites, and analyses from models. The diatom-dominated bloom began in mid April when the water column stabilized, not by solar warming, but rather by eddy-driven slumping of horizontal density gradients. The resulting bloom was patchy in both biomass and phytoplankton diversity, despite high, non-limiting concentrations of macronutrients. Magnitudes and relative proportions of net community productivity (NCP; determined from autonomous budgets of O2 and NO3) and net phytoplankton productivity (NPP; computed from ship-based photosynthetic parameters and float-based biomass and light) diverged as the bloom evolved, with higher fractions of particulate organic carbon (POC) consumed within the mixed layer as the bloom aged. Export productivity (EP; derived as the difference between NCP and accumulation rate of POC) was of similar magnitude during the May diatom bloom and the June picophytoplankton bloom. When silicic acid dropped to 1 µM, diatoms aggregated and sank; the deep flux event was dominated by resting spores of Chaetoceros. Although a short-lived event, it was ubiquitously observed by the 4 gliders and ship. An eddy-driven subduction event was likewise observed, indicating transport of otherwise non-sinking POC along isopycnals to depths of > 200 m. These striking export events reinforce the value of a persistent, distributed presence afforded by a network of autonomous platforms to catch and follow key, transient events. NAB 2008 demonstrated the power of autonomous platforms to decipher productivities and carbon fluxes at the patch scale, but left the enticing challenge of how to scale from the patch to the basin for another time.

Scientific Discipline: Planetary Sciences

10:20 - 10:35am PT - Results from the MAVEN Mission to Mars
Speaker: Bruce Martin Jakosky
Abstract: Click here for abstract

10:35 - 10:50am PT - Martian-Solar Wind Interaction Boundaries as Observed by MAVEN
Speaker: Jacob Gruesbeck
Abstract: Click here for abstract

10:50 - 11:05am PT - Evidence of Ion Heating at Low Altitudes in the Dayside Ionsphere at Mars
Speaker: Christopher M. Fowler
Abstract: Click here for abstract

11:05 - 11:20am PT - Structure of the Martian Ionosphere: Observations of Suprathermal Electrons by MAVEN SWEA
Speaker: David L. Mitchell
Abstract: Click here for abstract

11:20 - 11:35am PT - The Hot Oxygen Corona of Mars: Observations by MAVEN IUVS
Speaker: Justin Deighan
Abstract: Click here for abstract

11:35 - 11:50am PT - Oxygen Pickup Ions Measured by MAVEN Outside the Martian Bow Shock
Speaker: Ali Rahmati
Abstract: Click here for abstract

11:50am - 12:05pm PT - Solar Energetic Particle Events Observed by MAVEN
Speaker: Christina O. Lee
Abstract: Click here for abstract

12:05 - 12:20pm PT - Ion Heating and Magnetotail Losses at the Martian Ionosphere-Magnetosphere Interface
Speaker: James P. McFadden
Abstract: Click here for abstract

Scientific Discipline: Planetary Sciences

Speaker: William F. Bottke, Jr.

Abstract
The early bombardment of the inner solar system played a critical role in planetary evolution, but there is still considerable uncertainty about what happened when. Dynamical models suggest two major bombardment phases may have taken place: (i) a post-accretionary period where newly-formed worlds were struck by leftover planetesimals, and (ii) a late heavy bombardment period, possibly produced by conditions related to a violent reshuffling of the planets ~4.1-4.2 Gyr ago (Ga). If valid, a relative impact lull took place between the two bombardment phases. We explore the evidence for such doldrums in this talk. Consider:

a) Mars. Geochemical and meteorite evidence indicates the giant 10,600 × 8,500 km Borealis basin formed > 4.5 Ga. Many postulated basins forming afterwards, however, can be ruled out by the surprisingly pristine nature of the Borealis boundary in topography and gravity. Three of the four largest remaining basins, Hellas, Isidis, and Argyre, have superposed craters counts indicating they are < 4.1 Ga.

b) Asteroids. The oldest and most extensive sets of 39Ar-40Ar shock degassing ages, found within meteorites that were heavily shocked, shock-melted, or otherwise showed some evidence for having been part of a large collision, show age clusters between ~3.5-4.1 Ga and ~4.4-4.54 Ga. Using dynamical/impact heating models, it can be argued that relatively few projectiles were on planet-crossing orbits between ~4.1-4.4 Ga.

c) Moon. The Moon is probably 4.47 Ga, yet most sample evidence for basin-sized impacts may be < 4.2 Ga. The age gap is curious unless many basins were created close in time to the solidification of the lunar crust. Using collisional/dynamical models, it can be shown that many early basins and craters formed > 4.4 Ga. Here the early impactors may be surviving debris from the Moon-forming giant impact event; note that ejecta initially escaping the Earth-Moon system can come back over many tens of Myr. This would leave doldrums between ~4.2-4.4 Ga.

d) Earth. Early impacts may provide the means to indirectly make Hadean-era zircons (via burial of terrains by impact-derived melt). This could mean the paucity of > 4.2 Ga zircons is not solely a survival bias, but instead are doldrums. The zircon age distribution peak near ~4.15 Ga would then tell us about the onset of the late heavy bombardment.

Scientific Discipline: Planetary Sciences

Speaker: Alfred S. McEwen

Abstract
NASA mission proposals of today must promise “ground-breaking” new results. “Ground-breaking” is a buzzword, but sounds good to a geologist who likes to study active processes. Great progress in understanding active processes on the Moon and Mars has resulted from very-high-resolution (sub-meter scale) repeat imaging (monitoring) by LROC and HiRISE. Such changes include new impact craters and mass wasting on both the Moon and Mars. One martian surprise was not just finding that the gullies or ravines are forming today, but that they are forming in times and places with CO₂ frost on the ground. The geomorphology of these gullies is a perfect match for water-carved gullies on Earth, but the CO₂ buffers the ground and air temperatures to near 150 K, far too cold for liquid water to play a role. Snapshot geomorphology, even at very high resolution, does not enable a unique interpretation of geologic processes. Repeat imaging led to discovery of the martian Recurring Slope Lineae (RSL), which form at the warmest times and places and may be seeps of salty water. A source of water in a non-polar location is needed to support a future human presence on Mars, but Planetary Protection will be a challenge (or impossible). Jupiter’s moon Io is the ideal natural laboratory to understand groundbreaking volcanism and tectonism. Very large-scale energetic processes that have shaped the planets are active today on Jupiter’s moon Io, so this is the best place to study these processes. Is there active venting on Europa? We don’t know (yet) because we haven’t looked with the proper combination of resolution (

Scientific Discipline: Planetary Sciences

8:00 - 8:15am PT - Exogenous Carbonaceous Matter in Ancient Martian Sediments
Speaker: Stephen J. Mojzsis
Abstract: Click here for abstract

8:15 - 8:30am PT - The Provenance and Formation of Reduced Carbon Phases on Mars from the Study of Martian Meteorites
Speaker: Andrew Steele
Abstract: Click here for abstract

8:30 - 8:45am PT - The Volcanic History of Mars and Influences on Carbon Outgassing
Speaker: Jacob E. Bleacher
Abstract: Click here for abstract

8:45 - 9:00am PT - Biogenic Carbon on Mars: A Subsurface Chauvinistic Viewpoint
Speaker: Tullis C. Onstott
Abstract: Click here for abstract

9:00 - 9:15am PT - Mechanisms for Olivine Carbonation at the Nili Fossae / Isidis Basin Boundary, Mars: Evidence of Intense Surface Aqueous Activity
Speaker: John F. Mustard
Abstract: Click here for abstract

9:15 - 9:30am PT - Carbon Sequestration on Mars: Constraints from the Nili Fossae Carbonate Plains
Speaker: Bethany L. Ehlmann
Abstract: Click here for abstract

9:30 - 9:45am PT - Iron-Rich Carbonates as the Potential Source of Evolved CO₂ Detected by the Sample Analysis at Mars (SAM) Instrument in Gale Crater
Speaker: Brad Sutter
Abstract: Click here for abstract

9:45 - 10:00am PT - Evidence of Refractory Organic Matter Preserved in the Mudstones of Yellowknife Bay and the Murray Foundations
Speaker: Jennifer L. Eigenbrode
Abstract: Click here for abstract

Scientific Discipline: Planetary Sciences

Rocky Planets Basking in the Warmth of Other Suns
Speaker: John Asher Johnson

Abstract
Just four years ago the prospect of finding rocky planets around other stars was still the subject of science fiction—none had been found and reasonable estimates put us decades away from such momentous discoveries. All of that has changed very recently on the heels of the extraordinarily successful NASA Kepler mission. I will provide an overview of Kepler science and the new view it has provided us on the demographics of exoplanets throughout the Galaxy. In addition to the statistics of exoplanets, I will also show highlights from the many unusual individual discoveries that have expanded our understanding of planet formation and allowed us to view our Solar System within a much broader context than ever before.

Scientific Discipline: Planetary Sciences

1:40 - 1:55pm PT - Evolution of H20 Related Species in the Natural Coma of 67P
Speaker: Andre Michel Bieler
Abstract: Click here for abstract

1:55 - 2:10pm PT - The Activity of Comet 67P/Churyumov-Gerasimenko as Seen by Rosetta/OSIRIS
Speaker: Holger Sierks
Abstract: Click here for abstract

2:10 - 2:25pm PT - First Detection of Diamagnetic Cavity at 67P/Churyumov-Gerasimenko
Speaker: Charlotte Goetz
Abstract: Click here for abstract

2:25 - 2:40pm PT - VIRTIS/Rosetta Observes Comet 67P/Churyumov-Gerasimenko: Nucleus and Coma Derived Composition and Physical Properties
Speaker: Fabrizio Cappaccioni
Abstract: Click here for abstract

2:40 - 2:55pm PT - Coma Dust Environment Observed by GIADA During the Perihelion of 67P/Churyumov-Gerasimenko
Speaker: Alessandra Rotundi
Abstract: Click here for abstract

2:55 - 3:10pm PT - The Nucleus and Coma of Comet 67P/C-G at Milimeter and Submilimeter Wavelengths as Seen by MIRO
Speaker: Mark D. Hofstadter
Abstract: Click here for abstract

3:10 - 3:25pm PT - Ultraviolet Emission from CF's Coma: Fluorescence Versus Electron-Impact Excitation
Speaker: Eric Schindhelm
Abstract: Click here for abstract

3:25 - 3:40pm PT - Constraining the Bulk Dust to Ice Ratio and Compressive Strength for Comet Churyumov-Gerasimenko Using CONSERT Radar Observations
Speaker: Essam Heggy
Abstract: Click here for abstract

Scientific Discipline: Planetary Sciences

8:00 - 8:18am PT - A First Look at the Geology of Charon
Speaker: John R. Spencer
Abstract: Click here for abstract

8:18 - 8:30am PT -   Charon as Seen by New Horizons in the Infrared
Speaker: Cristina Dalle Ore
Abstract: Click here for abstract

8:30 - 8:42am PT - Comparisons Between New Horizons Results and Long-Term Monitoring of Pluto
Speaker: Marc W. Buie
Abstract: Click here for abstract

8:42 - 8:54am PT - Processes Modifying Cratered Terrains on Pluto
Speaker: Jeffrey M. Moore
Abstract: Click here for abstract

8:54 - 9:06am PT -  Geomorphic Evolution of Sputnik Planum and Surrounding Terrain
Speaker: Alan D. Howard
Abstract: Click here for abstract

9:06 - 9:18am PT - Geomorphological Mapping of Sputnik Planum and Surrounding Terrain on Pluto
Speaker: Oliver L. White
Abstract: Click here for abstract

9:18 - 9:30am PT - Craters on Pluto and Charon: The Influence of Low Gravities, Low Impact Speeds, and Unique Ices
Speaker: Kelsi N. Singer
Abstract: Click here for abstract

9:30- 9:42am PT - Radii and Shape of Pluto and Charon: Preliminary Results from New Horizons
Speaker: Francis Nimmo
Abstract: Click here for abstract

9:42 - 10:00am PT - New Insights into the Structure, Origin, and Evolution of Pluto and Charon
Speaker: William B. McKinnon
Abstract: Click here for abstract

Scientific Discipline: Public Affairs

8:00 - 8:15am PT - Translating Volcano Hazards Research in the Cascades Into Community Preparedness
Speaker: John W. Ewert
Abstract: Click here for abstract

8:15 - 8:30am PT -  Putting Research to Work for Monitoring Volcanic Hazards and Enhancing Public Safety
Speaker: Jeffrey Todd Freymueller
Abstract: Click here for abstract

8:30 - 8:45am PT - The Volcano Disaster Assistance Program: Working with International Partners to Reduce the Risk from Volcanic Eruptions Worldwide
Speaker: Gari C. Mayberry
Abstract: Click here for abstract

8:45 - 9:00am PT - International Collaboration on Building Local Technical Capacities for Monitoring Volcanic Activity at Pacaya Volcano, Guatemala
Speaker: Rudiger P. Escobar-Wolf
Abstract: Click here for abstract

9:00 - 9:15am PT -  Incorporating Community Knowledge to Lahar Hazard Maps: Canton Buenos Aires Case Study, at Santa Ana (Ilamatepec) Volcano
Speaker: Jorge V. Bajo
Abstract: Click here for abstract

9:15 - 9:30am PT - Development of Scientific Tools at the USGS to Prepare for Ash-Producing Eruptions
Speaker: Marianne Guffanti
Abstract: Click here for abstract

9:30 - 9:45am PT - Large, Moderate or Small? The Challenge of Measuring Mass Eruption Rates in Volcanic Eruptions
Speaker: Magnus Tumi Gudmundsson
Abstract: Click here for abstract

9:45a- 10:00am PT - Advances in Monitoring, Modelling and Forecasting Volcanic Ash Plumes Over the Past 5 Years and the Impact on Preparedness From the London VAAC Perspective
Speaker: Deborah S. Lee
Abstract: Click here for abstract

Scientific Discipline: Public Affairs

10:20 - 10:35am PT - Integrating Infrastructure-Relevant Climate Projections Into City Planning: Learning from Boulder CO, Austin TX and Washington DC
Speaker: Anne Marie K. Stoner
Abstract: Click here for abstract

10:35 - 10:50am PT - Determinants of Urban Resource Use and Resilience: A Comprehensive Framework
Speaker: Patricia Romero-Lankao
Abstract: Click here for abstract

10:50 - 11:05am PT - Integrated Framework for an Urban Climate Adaptation Tool
Speaker: Olufemi Omitaomu
Abstract: Click here for abstract

11:05 - 11:20am PT - Graceful Failure, Engineering, and Planning for Extremes: The Engineering for Climate Extremes Partnership (ECEP)
Speaker: Cindy L. Bruyere
Abstract: Click here for abstract

11:20 - 11:35am PT -  Toolbox for Urban Mobility Simulation: High Resolution Population Dynamics for Global Cities
Speaker: Budhendra L. Bhaduri
Abstract: Click here for abstract

11:35 - 11:50am PT - Safe Shores and Resilient Transit Corridors: Using Science, Design, and Stakeholder Partnerships to Address Connecticut’s Coastal Vulnerabilities
Speaker: Rebecca A. French
Abstract: Click here for abstract

11:50am - 12:05pm PT - Translating Knowledge Into Action: Supporting Adaptation in Australia’s Coastal Zone through Information Provision and Decision Support
Speaker: Jean Patricia Palutikof
Abstract: Click here for abstract

12:05 - 12:20pm PT - Framework for Vulnerability Assessment of Coastal Infrastructure
Speaker: Patrick S. Obrien
Abstract: Click here for abstract

Scientific Discipline: Paleoceanography and Paleoclimatology

8:00 - 8:15am PT - Sea-Level Change During Hothouse, Cool Greenhouse, and Icehouse Worlds
Speaker: Kenneth G. Miller
Abstract: Click here for abstract

8:15 - 8:30am PT - Simulating a Dynamic Anarctic Ice Sheet in the Early to Middle Miocene
Speaker: Edward Gasson
Abstract: Click here for abstract

8:30 - 8:45am PT - Eight Million Years of Land-Based Antarctic Ice Sheet Stability Recorded by In Situ ¹⁰Be from the ANDRILL-1B Core
Speaker: Jeremy D. Shakun
Abstract: Click here for abstract

8:45 - 9:00am PT - The Impact of Dynamic Topography Change on Antarctic Ice Sheet Stability During the Mid-Pliocene Warm Period
Speaker: Jacqueline Austermann
Abstract: Click here for abstract

9:00 - 9:15am PT - WAIS-ting Away Again in East Antarctica: Sirius-ly Searching for that Lost Shaker of Diatoms
Speaker: Reed P. Scherer
Abstract: Click here for abstract

9:15 - 9:30am PT - A Global Perspective on the Timing and Nature of Sub-Orbital Sea Level Oscillations During MIS 5e
Speaker: Andrea Dutton
Abstract: Click here for abstract

9:30 - 9:45am PT - Revisiting Tectonic Corrections Applied to Pleistocene Sea-Level Highstands
Speaker: Jessica R. Creveling
Abstract: Click here for abstract

9:45 - 10:00am PT - Recent Adavances in the Compilation of Holocene Relative Sea-Level Database in North Ameica
Speaker: Ben Horton
Abstract: Click here for abstract

Scientific Discipline: Paleooceanography and Paleoclimatology

Searching for Tipping Points in Pleistocene Climate: Are They Real? Are They Portents for the Future?
Speaker: Alan C. Mix

Abstract
Paleoscientists seek fundamental knowledge of Earth systems, and have unique views of system dynamics on the timescales longer than recent observations. This is important, because some processes that may control the trajectory of change in the not-so-distant future are not well illustrated or constrained in the short history of instrumental observations; paleo data offer our only observational window on these longer scales. But paleo vision is also a bit blurry, and sometimes biased. It matters how we approach the records to focus on the right things, and it matters how we communicate our insights so that we can teach models to approximate real Earth system behaviors. In the six decades since Cesare Emiliani set us on the path of quantitative observational paleoscience, we’ve observed more and more. Each year brings more “proxies,” more sites, more resolution, and the more we look the more we find interpretable signals. This data complexity makes the paleo literature daunting to outsiders; it is hard to get past the stories. Most of our narratives are grounded in linear systems, focusing on forcing and response, and we data generators struggle to infer even modest nonlinearity. But the concept of massive nonlinearity, tipping points, has recently entered the public consciousness, and the search is on anew for such events in paleo data. The reality of tipping points as well as the processes that may drive such events are not yet fully clear, but the search is essential because if humanity does indeed push the Earth system across an irreversible tipping point into a new state, we need to know how this might play out and over what time frames. Can we really learn about such occurrences, and the processes that control them, in paleo records? Do we need to think about the past differently? Will this change how we think about the future? Will it inform what we do about the future? Emiliani thought it should. This lecture will explore how.

 
Speaker
Dr. Richard Alley, Evan Pugh Professor of Geosciences at Pennsylvania State University

Abstract
We humans have always moved ahead by getting something else to do our work for us. But. we have consistently over done it, burning trees and whales far faster than they grew back, and then suffering the consequences. Fossil fuels are next, with our present path likely to lead to scarcity after highly expensive global warming. Fortunately, the science, engineering and design that gave us smart phones can also give us an economical, sustainable energy system that can power everyone almost forever.

Scientific Discipline: Seismology

Speaker: Kazushige Obara

Abstract
Progress of seismic observation network brings breakthroughs in the earth science at each era. High sensitivity seismograph network (Hi-net) was constructed by National Research Institute for Earth Science and Disaster Prevention (NIED) as a national project in order to improve the detection capability of microearthquake after disastrous 1995 Kobe earthquake. Hi-net has been contributing to not only monitoring of seismicity but also producing many research results like as discoveries of non-volcanic tremor and other slow earthquakes. More important thing is that we have continued to make efforts to monitor all of data visually and effectively.

The discovery of tremor in southwest Japan stimulated PGC researchers to search similar seismic signature in Cascadia because of a couple of common features in the tremor in Japan and slow slip event (SSE) they already discovered in Cascadia. At last, episodic tremor and slip (ETS) was discovered, then the SSE associated with tremor was also detected in Japan by using the tilting data measured by high-sensitivity accelerometer attached with the Hi-net. This coupling phenomena strengthened the connection between seismology and geodesy. Widely separated spectrum of tremor and SSE motivated us to search intervened phenomena, then we found very low frequency earthquake during ETS episode. These slow earthquakes obey a scaling law different from ordinary earthquake. This difference is very important to resolve the earthquake physics.

Hi-net is quite useful for not only three-dimensional imaging of underground structure beneath the Japan Islands, but also resolving deep Earth interior by using teleseismic events or ambient noises and source rupture process of large earthquakes by using back-projection analysis as a remote array. Hi-net will continue to supply unexpected new discoveries. I expect that multiple installation of similar dense seismic array in the world will give us great opportunity to discover more important and explore a new regime in the earth science.

Scientific Discipline: SPA-Solar and Heliospheric Physics

4:00 - 4:05pm PT - Introductory Remarks
Speaker: David G. Sibeck

4:05 - 5:00pm PT - The Sun from the Perspective of an Observer
Speaker: Philip H. Scherrer

Abstract
This talk will reflect on issues and pleasures of observing the Sun from the Earth and from space over four sunspot cycles. Parker and those who preceded and follow his early estimates of how our star should/might/could work need to compare their models with the real Sun. The true test of a model is how well it explains reality. Observers try to make their own estimates of how the Sun does work based on observable proxies for the physical quantities of interest. It the best of times, the models match the observations. The results are seldom simple due to, at least, limitations of both models and observations.

Scientific Discipline: SPA-Magnetospheric Physics

1:40 - 1:56pm PT - Fifty Years of Space Weather Forecasting from Boulder
Speaker: Thomas E. Berger
Abstract: Click here for abstract

1:56 - 2:12pm PT - Simplified Solutions to Predicting the Magnetic Vectors Within CMEs
Speaker: Neel Savani
Abstract: Click here for abstract

2:12 - 2:28pm PT - Forecasting the Radiation Belts for Satellites Undergoing Electric-Orbit Raising
Speaker: Richard Bertram Horne
Abstract: Click here for abstract

2:28 - 2:44pm PT - Forecasting Thermosphere Density: an Overview
Speaker: Sean Bruinsma
Abstract: Click here for abstract

2:44 - 2:58pm PT - Forecasting keV-electrons in the Inner Earth's Magnetosphere Responsible for Surface Charging
Speaker: Natalia Y. Ganushkina
Abstract: Click here for abstract

2:58 - 3:12pm PT - An Ensemble Approach to Extreme Space Weather Event Probability -- A First Look
Speaker: Seth Jonas
Abstract: Click here for abstract

3:12 - 3:26pm PT - Nowcasting Ground Magnetic Perturbations with the Space Weather Modeling Framework
Speaker: Daniel T. Welling
Abstract: Click here for abstract

3:26 - 3:40m PT - Modeling the Ionosphere-Thermosphere-Electrodynamics System for Space Weather Specifications, Forecasts and Applications
Speaker: Robert Walter Schunk
Abstract: Click here for abstract

Scientific Discipline: SPA-Magnetospheric Physics

5:00 - 5:05pm PT - Introductory Remarks
Speaker: David G. Sibeck

5:05 - 6:00pm PT - Van Allen Lecture: Nature's Pallete
Speaker: Michelle F. Thomsen

Abstract
Like an artist’s palette, Nature has a set of common physical processes to employ to make a magnetosphere. The nature of a particular work of art depends on how much of each of the colors is used and how they are combined on the canvas. In much the same way, the nature of a magnetosphere is determined by the particular properties of a given planet and how those properties influence the dynamical significance of the various processes. We will examine some of the processes in Nature’s palette and see how their importance varies from magnetosphere to magnetosphere within our own solar system. Comparing actual realizations of magnetospheres to which we have in-situ access enables us to see the interplay between the physical processes and the peculiar conditions of each body. As we contemplate the extra-solar planets we are now discovering, we need to consider other possible combinations of colors from this palette: What other wonderful and exotic magnetospheres might exist throughout the universe?

Scientific Discipline: Tectonophysics

1:40 - 1:55pm PT - Rigidity and Definition of Caribbean Plate Motion from COCONet and Campaign GPS Observations
Speaker: Glen S. Mattioli
Abstract: Click here for abstract

1:55 - 2:10pm PT - Areas of Unsolved Problems in Caribbean Active Tectonics
Speakers: Paul Mann
Abstract: Click here for abstract

2:10 - 2:25pm PT - The Last Interglacial Period at Guantanamo Bay, Cuba and an Estimate of Late Quaternary Tectonic Uplift Rate in a Strike-Slip Regime
Speakers: Eugene S. Schweig
Abstract: Click here for abstract

2:25 - 2:40pm PT - Imaging the Crustal and Subducted Slab Structure Beneath Puerto Rico Using Receiver Function Analysis
Speakers: Elizabeth A. Vanacore
Abstract: Click here for abstract

2:40 - 2:55pm PT - What Drives Micro-Plate Motion and Deformation in the Northeastern Caribbean Plate Boundary Region?
Speakers: Rob M.A. Govers
Abstract: Click here for abstract

2:55 - 3:10pm PT - 20th-Century Strain Accumulation on the Lesser Antilles Megathrust Based on Coral Microatolls
Speakers: Belle Philibosian
Abstract: Click here for abstract

3:10 - 3:25pm PT - The Two Subduction Zones of the Southern Caribbean: Lithosphere Tearing and Continental Margin Recycling in the East, Flat Slab Subduction and Laramide-Style Uplifts in the West
Speakers: Alan Levander
Abstract: Click here for abstract

3:25 - 3:40pm PT - Forearc Morphotectonics and Megathrust Earthquakes Along the Middle America Convergent Margin, Nicoya Peninsula, Costa Rica
Speakers: Jeffrey S. Marshall
Abstract: Click here for abstract

Scientific Discipline: Tectonophysics

Subduction Faults As We See Them in the 21st Century
Speaker: Kelin Wang

Abstract
Major advances in geophysical monitoring and field and laboratory studies have reshaped our views of subduction faults over the past 15 years. The beginning of the 21^st century saw the discovery of Episodic Tremor and Slip, followed by the discovery of opposing motion of coastal and inland GPS sites decades after the giant megathrust earthquakes of Chile (1960) and Alaska (1964). The burst of great earthquakes since 2004 caused tragic losses, but the resultant massive observational data greatly improved our knowledge. Today, we know that all subduction faults are extremely weak, usually represented by apparent friction coefficients lower than 0.05. Smooth faults that have produced giant earthquakes are the weakest. Geometrical irregularities such as subducting seamounts give rise to stronger faults, but these faults creep. Rupture-zone average stress drops in great earthquakes are as small as 2 – 5 MPa but are still a significant fraction of the fault strength. Therefore, it takes time to rebuild fault stress to the level of failure, consistent with great earthquakes having long recurrence intervals. The process of stress rebuilding is strongly affected by the viscoelastic mantle rheology. Because of viscoelastic stress relaxation, most of the forearc area continues to move seaward following a great earthquake but gradually reverses direction to move landward. Advanced monitoring in the new century has revealed a wide range of slip behaviors of the shallowest part the megathrust, such as huge trench-breaching coseismic slip, slip that generates large tsunamis but not strong shaking, postseismic creep, and episodic slow slip. Rapidly expanding efforts of seafloor geodesy and seismology and ocean drilling allow us to study these phenomena in close range. The deeper part of subduction faults where the slab is in contact with the serpentinized upper-plate mantle is understood to be lined with weak hydrous minerals such as talc that cause slab-mantle decoupling but retard seismic slip. With increasing depth, frictional slip gives way to viscous shear. At a depth around 70-80 km, the subduction fault is terminated. Below this depth, the mantle material travels with the slab to form mantle-wedge corner flow, as inferred from forearc heat flow observations and temperature conditions for arc volcanism.

Scientific Discipline: Tectonophysics

1:40 - 1:55pm PT - Seismicity and Structure of the Incoming Pacific Plate Subducting into the Japan Trench off Miyagi
Speaker: Koichiro Obana
Abstract: Click here for abstract

1:55 - 2:10pm PT - JFAST Constraints on the Tohoku Earthquake Fault
Speaker: Emily E. Brodsky
Abstract: Click here for abstract

2:10 - 2:25pm PT - Slip to the Trench for Great Subduction Earthquakes
Speaker: James J. Mori
Abstract: Click here for abstract

2:25 - 2:40pm PT - Boron Isotopic Fractionation During the First ~50 km of Sediment Subduction in the Nankai Trough, Japan
Speaker: Maureen D. Feineman
Abstract: Click here for abstract

2:40 - 2:55pm PT - Frictional Behavior of Carbonate-Rich Sediments in Subduction Zones
Speaker: Hannah S. Rabinowitz
Abstract: Click here for abstract

2:55 - 3:10pm PT - Long-term Observation of Seafloor Disturbances by Array of Pressure Gauges
Speaker: Yoshio Fukao
Abstract: Click here for abstract

3:10 - 3:25pm PT - Postseismic Deformation of the 2011 Tohoku-Oki Earthquake Revealed by Repeated GPS/Acoustic Observations
Speaker: Fumiaki Tomita
Abstract: Click here for abstract

3:25 - 3:40pm PT - Change in Anisotropic P-wave Velocity Observed by Seafloor Borehole Observatory C0002G in the Nankai Trough Subduction Zone
Speaker: Eiichiro Araki
Abstract: Click here for abstract

Scientific Discipline: Town Hall

Speakers:
D.J. Patil, The White House Office of Science and Technology Policy

Abstract
DJ Patil was appointed as the First US Chief Data Scientist and Deputy Chief Technology Officer for Data Policy earlier this year.  DJ is credited with originating and popularizing the term “data scientist” and previously held leadership positions in LinkedIn, eBay, Skype, PayPal and other technology ventures.  His White House role includes helping guide the United States and Office of Science and Technology Policy (OSTP) in data policy and investments in data and related technology, and helping guide the precision medicine initiative.  He will speak on these roles and answer questions about Earth and space science data and technology in a moderated discussion.

Scientific Discipline: Town Hall

Speakers:
Christine Williams, University of Texas at Austin
Meg Urry, Yale University
Margaret Leinen, Scripps Institution of Oceanography
Eric Davidson, University of Maryland Center for Environmental Science Appalachian Laboratory
Blair Schneider, University of Kansas
Erika Marin-Spiotta, University of Wisconsin-Madison
Mary Anne Holmes, University of Nebtraska-Lincoln

Abstract
Recent high-profile events in the news have raised awareness of the problem of harassment (including sexual harassment) in science and academia. These events have highlighted the need for support mechanisms for the targets of inappropriate behavior, as well as the need for suitable institutional response to deter continued misconduct. This professional misconduct often preferentially targets women, impacting their personal and professional well-being; although men can also be harassment targets. Research confirms the extent of harassment in academic environments and in disciplines with low diversity, where the lack of established support networks can lead to feelings of vulnerability and professional insecurity. Another problem identified by research on harassment is the scarcity of well-defined resources for reporting and responding to inappropriate behavior, and the perceived risk that the victims’ careers may be jeopardized if they speak out. This session will provide information on lessons-learned from recent research on sexual harassment in the scientific community, and discuss examples of institutional and individual responses. This interactive session will seek input from participants on suggested actions for the AGU and other scientific societies in helping to address these issues. Sponsored by AGU, the Association for Women Geoscientists (AWG), and the Earth Science Women’s Network (ESWN).

Speakers
Former Vice President Al Gore, chairman of The Climate Reality Project
Tamara Dickinson, Ph.D., Principal Assistant Director for Environment and Energy, White House Office of Science and Technology Policy (OSTP)
Adam Szabo, NASA Goddard Space Flight Center
Thomas Immel, University of California Berkeley
Stewart Brand, prominent American writer, futurist and envrionmentalist
Stacey Boland, Jet Propulsion Laboratory

Abstract
Citizens of the world were awe struck when they saw the “Blue Marble” image of Earth In 1972, taken by the crew of Apollo 17; one of the most iconic photos of our time, and one that inspired a new generation of scientists and explorers. Today, Earth observations are being collected and transmitted by the Deep Space Climate Observatory (DSCOVR) satellite that are similarly inspirational. From an orbital position at Lagrange point 1, approximately one million miles away, instruments on DSCOVR – including the Earth Polychromatic Imaging Camera (EPIC) and the National Institute of Standards and Technology Advanced Radiometer (NISTAR) – are providing valuable data on a range of Earth properties and the Earth’s radiation balance. DSCOVR is transmitting full disk, regularly updated images of Earth, giving everyone the opportunity to see the “Blue Marble” in a new, exciting way. This session will provide an opportunity to discuss creative ideas for using non-traditional vantage points like L1 to advance Earth science and observations, while recognizing the new contributions of the DSCOVR mission.

Scientific Discipline: Union

1:40 - 2:00m PT - Scientific Reticence and Sea Level Rise (Invited Talk)
Speaker: James E. Hansen
Abstract: Click here for abstract

2:00 - 2:20pm PT - If You See Something, Say Something...More
Speaker: Michael E. Mann
Abstract: Click here for abstract

2:20 - 2:40pm PT - Reticence, Accuracy and Efficacy
Speaker: Naomi Oreskes
Abstract: Click here for abstract

2:40 - 3:00pm PT - The Role of Religious and Scientific Leaders in Bringing Awareness to the Urgency of Climate Change
Speaker: Veerabhadran Ramanathan
Abstract: Click here for abstract

3:00 - 3:20pm PT - The Solutions Project: Educating the Public and Policy Makers About Solutions to Global Warming, Air Pollution, and Energy Security
Speaker: Mark Z. Jacobson
Abstract: Click here for abstract

3:20 - 3:40pm PT - Panel Discussion

Scientific Discipline: Union

Speakers
Peter Diamandis, XPRIZE
Jyotika Virmani, XPRIZE
David Schwartz, Shell
Dr. Richard Spinrad, NOAA
Paul Bunje, XPRIZE

Scientific Discipline: Union

4:00 - 4:10pm PT - Introductory Remarks

4:10pm - 4:32pm PT - Building a Regional Collaborative for Climate Literacy
Speakers: Oksana Shcherba
Abstract: Click here for abstract

4:32 - 4:54pm PT - Designing at Scale: Lessons in Relevance, Quality, and Equity from ChangeScale, a Bay Area Environmental Education Collaborative
Speakers: Elizabeth C. Babcock
Abstract: Click here for abstract

4:54 - 5:16pm PT - Community, Collective or Movement? Evaluating Theoretical Perspectives on Network Building
Speakers: William Spitzer
Abstract: Click here for abstract

5:16 - 5:38pm PT - Blue Sky Founders Forum - Advancing Environmental Literacy Through Funder Collaboration
Speakers: Angie Chen
Abstract: Click here for abstract

5:38 - 6:00pm PT - Panel Discussion

Scientific Discipline: Union

10:00 - 10:10am PT - Introductory Remarks

10:10 - 11:00am PT - Presidential Forum
Speaker: Elon Musk

Scientific Discipline: Union

10:20 - 10:35am PT - GPS Imaging of Solid Earth's Flex and Flow: A New Paradigm
Speaker: Geoffrey Blewitt
Abstract: Click here for abstract

10:35 - 10:50am PT - Development of a GNSS-Enhanced Tsunami Early Warning System
Speaker: Gerald W. Bawden
Abstract: Click here for abstract

10:50 - 11:05am PT - Vegetation, Smegetation: How InSAR Research on Tectonics and Land Surface Change has Expanded from the Deserts to the Rain Forests and Beyond
Speaker: Rowena B. Lohman
Abstract: Click here for abstract

11:05 - 11:20am PT - Post-Earthquake Geology in the Era of Ubiquitous Point Clouds
Speaker: Michael E. Oskin
Abstract: Click here for abstract

11:20 - 11:35am PT - New Radar Altimeter Missions are Providing a Dramatically Sharper Image of Global Marine Tectonics
Speaker: Emmanuel Garcia
Abstract: Click here for abstract

11:35 - 11:50am PT - An Ocean Science Revolution: 23 Years of Precision Altimetry
Speaker: Josh K. Willis
Abstract: Click here for abstract

11:50am - 12:05pm PT - GRACE: Providing a New View of the Earth
Speaker: Michael M. Watkins
Abstract: Click here for abstract

12:05 - 12:20pm PT - The Vital Contributions of Geodesy to Our Understanding of the Ice Sheets of Antarctica and Greenland
Speaker: Helen Amanda Fricker
Abstract: Click here for abstract

Scientific Discipline: Union

1:40 - 2:00pm PT - The Pain and the Gain of Rescuing Historic Science Data: The Nimbus Data Rescue Project
Speaker: David W. Gallaher
Abstract: Click here for abstract

2:00 - 2:20pm PT - If an Antelope is a Document, Then a Rock is Data: Preserving Earth Science Samples for the Future
Speaker: Sarah Ramdeen
Abstract: Click here for abstract

2:20 - 2:40pm PT - The Challenge of Assimilating Older Data and Samples Into Digital Datasets and Sample Collections
Speaker: Margaret Leinen
Abstract: Click here for abstract

2:40 - 3:00pm PT - Preserving the Science Legacy from the Apollo Missions to the Moon
Speaker: Nancy Stella Todd
Abstract: Click here for abstract

3:00 - 3:20pm PT - Curse of the Zombie Petabytes
Speaker: Jean-Bernard H. Minster
Abstract: Click here for abstract

3:20 - 3:40pm PT - Panel Discussion

Scientific Discipline: Union

12:30 - 12:40pm PT - Introductory Remarks

12:40 - 1:30pm PT - Union Agency Lecture
Speaker: Dr. France A. Córdova

Scientific Discipline: Union

8:00 - 8:24am PT - Hydrologic Regulation of Global Geochemical Cycles
Speaker: Katharine Maher
Abstract: Click here for abstract

8:24 - 8:48am PT - Macelwane Medal Talk: Mars Exploration - A Look Forward
Speaker: Bethany L. Ehlmann
Abstract: Click here for abstract

8:48 - 9:12am PT - Atmospheric Aerosols in a Changing World
Speaker: Colette L. Heald
Abstract: Click here for abstract

9:12 - 9:36am PT - Predictions of Space Physics are Difficult, Especially When They are About the Future
Speaker: Paul Cassak
Abstract: Click here for abstract

9:36 - 10:00am PT - Consequences for an Alternative Earth Composition: A Decade of Insight
Speaker: Matthew G. Jackson
Abstract: Click here for abstract

Scientific Discipline: Union

10:20 - 10:50am PT - Soil Moisture in the Climate System
Speaker: Randal D. Koster
Abstract: Click here for abstract

10:50 - 11:20am PT - Role of Soils in Hydrologic Response to Climate Extremes and Land Use Change
Speaker: Bridget R. Scanlon
Abstract: Click here for abstract

11:20 - 11:50am PT - Soils as a Solution: The Potential of Rangelands to Contribute to Climate Change Mitigation
Speaker: Whendee L. Silver
Abstract: Click here for abstract

11:50 - 12:20pm PT - Climate and Soil Interactions in the Context of Climate, Water, Ecosystems and Food Systems
Speaker: Jerry Hatfield
Abstract: Click here for abstract

Scientific Discipline: Union

1:40 - 1:55pm PT - Incomplete Décollement Rupture in the 25 April 2015 Gurkha Earthquake; Implications for Past and Future Himalayan Earthquakes
Speaker: Rebecca O. Bendick
Abstract: Click here for abstract

1:55 - 2:10pm PT - Poster Presentation

2:10 - 2:25pm PT - The Advanced Rapid Imaging and Analysis (ARIA) Project’s Response to the April 25, 2015 M7.8 Nepal Earthquake: Rapid Measurements and Models for Science and Situational Awareness
Speaker: Susan E. Owen
Abstract: Click here for abstract

2:25 - 2:40pm PT - Salient Features of the 2015 Gorkha, Nepal Earthquake in Relation to Earthquake Cycle and Dynamic Rupture Models
Speaker: Jean Paul Ampuero
Abstract: Click here for abstract

2:40 - 2:55pm PT - Performance of Built Environment in the 2015 Gorkha Earthquake and its Implications on Seismic Risk Mitigation Strategies
Speaker: Durgesh C. Rai
Abstract: Click here for abstract

2:55 - 3:10pm PT - Macroseismic Intensities from the 2015 Gorkha, Nepal, Earthquake
Speaker: Stacey Servito Martin
Abstract: Click here for abstract

3:10 - 3:25pm PT - Landslide Distribution Resulting from the 2015 Gorkha, Nepal Earthquake Sequence
Speaker: Brian D. Collins
Abstract: Click here for abstract

3:25 - 3:40pm PT - Earthquake Forecasts for Gorkha Immediately Following the 25th April M=7.8 Mainshock
Speaker: Margartia Segkou
Abstract: Click here for abstract

Scientific Discipline: Union

4:00 - 4:13pm PT - What We Can Learn from the Next Large Volcanic Eruption
Speaker: Alan Robock
Abstract: Click here for abstract

4:13 - 4:26pm PT - What Do We Need to Know to Model the Microphysical Evolution of Volcanic Clouds and How Can We Make These Measurements?
Speaker: Jason M. English
Abstract: Click here for abstract

4:39 - 4:52pm PT - Long-Range Transport, Air Quality and Climate Impacts of Volcanic Sulfur From the 2014-2015 Eruption at Holuhraun (Bárðarbunga, Iceland)
Speaker: Anja Schmidt
Abstract: Click here for abstract

4:52 - 5:05pm PT -  Observing a Chemically and/or Climatically Important Volcano: Facilitating Rapid Response to an Unanticipated Yet Inevitable Event
Speaker: Jack A. Kaye
Abstract: Click here for abstract

5:05 - 5:18pm PT - Volcanic Aerosols From Satellites: Current and Emerging Capabilities
Speaker: Pawan K. Bhartia
Abstract: Click here for abstract

5:18 - 5:31pm PT - Airborne Stratospheric Observations of Major Volcanic Eruptions: Past and Future
Speaker: Paul A. Newman
Abstract: Click here for abstract

5:31 - 5:44pm PT - An Airborne Mission to Study Background Sulfur and Prepare for a Rapid Response to a Large Volcanic Eruption
Speaker: Ru-Shan Gao
Abstract: Click here for abstract

5:44 - 6:00pm PT - Measuring the Stratospheric Aerosol Size Distribution Profile Following the Next Big Volcanic Eruption. What is Required?
Speaker: Terry Deshler
Abstract: Click here for abstract

Scientific Discipline: Union

8:00 - 8:20am PT - Why is Understanding When Plate Tectonics Began Important for Understanding Earth?
Speaker: Jun Korenaga
Abstract: Click here for abstract

8:20 - 8:40am PT -  When Did Plate Tectonics Begin?
Speaker: Michael Brown
Abstract: Click here for abstract

8:40 - 9:00am PT - Origin of Plate Tectonics: Grain-Damage, Inheritance and Hysteresis
Speaker: David Bercovici
Abstract: Click here for abstract

9:00 - 9:20am PT - What Was Earth's Tectonic Style Before Plate Tectonics?
Speaker: Patrice F. Rey
Abstract: Click here for abstract

9:20 - 9:40am PT -  Plate Tectonics and Planetary Evolution: Implications for Understanding Exoplanets
Speaker: Linda T. Elkins-Tanton
Abstract: Click here for abstract

9:40 - 10:00am PT - DISCUSSION: When and How Did Plate Tectonics Begin, What Came Before, and Why is this Controversy important for Understanding the Earth and Exoplanets?
Speaker: Robert J. Stern
Abstract: Click here for abstract

Scientific Discipline: Union

10:20 - 10:35am PT - Glacier Loss and Emerging Hydrologic Vulnerabilities in the Peruvian Andes
Speaker: Bryan G. Mark
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10:35 - 10:50am PT - The Tropical Andes Without Snow and Ice – Impacts, Uncertainties and Challenges Ahead
Speaker: Mathias F. Vuille
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10:50 - 11:05am PT - Warming Mountains, Earlier Runoff and Declining Snowpack in Western North America
Speaker: Daniel R. Cayan
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11:05 - 11:20am PT - Glacier Melt on the Third Pole
Speaker: Tandong Yao
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11:35 - 11:50am PT - Mountains of Central Asia in the Warmer World
Speaker: Maria Shahgedanova
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Scientific Discipline: Atmospheric Sciences

4:00 - 4:24pm PT - Fracking in the Face of Global Climate Change
Speakers: Peter Peterson
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4:24pm - 4:48pm PT - Implications of Abundant Gas and Oil for Climate Forcing
Speakers: James Edmonds
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4:48 - 5:12pm PT - Oil Production, The Price Crash and Uncertainty in Climate Change
Speakers: James W. Murray
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5:12 - 5:36pm PT - Unconventional Liquids, Peak Oil and Climate Change
Speakers: John David Hughes
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5:36 - 6:00pm PT - What Geological, Economic, or Policy Forces Might Limit Fossil Fuel Production?
Speakers: Richard Heinberg
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Scientific Discipline: Union

8:00 - 8:30am PT - Sustaining an Online, Shared Community Resource for Models, Robust Open source Software Tools and Data for Volcanology – the Vhub Experience
Speakers: Abani K. Patra
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8:30 - 9:00am PT - HydroTerre: Towards an Expert System for Scaling Models from Hillslopes to Major River Basins
Speakers: Lorne N. Leonard
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9:00 - 9:30am PT - Designing Collaborative Developmental Standards by Refactoring of the Earth Science Models, Libraries, Workflows and Frameworks
Speakers: Eugene Mirvis
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9:30 - 10:00am PT - OntoSoft: A Software Commons for Geosciences
Speakers: Yolanda Gil
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Scientific Discipline: Union

10:20 - 10:44am PT - Best Practices and Processes for Choosing Research Priorities
Speakers: Melbourne G. Briscoe
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10:44 - 11:08am PT - NSF Perspective on Engaging the NRC and the Community in Developing Priorities
Speakers: Roger M. Wakimoto
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11:08 - 11:32am PT - Strategic Planning and NRC Decadal Survey Experience
Speakers: Conrad C. Lautenbacher, Jr.
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11:32 - 11:56am PT - The Space Science Decadal Surveys: Lessons Learned and Best Practices
Speakers: Stacey W. Boland
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11:56am - 12:20pm PT - Vision and Voyages: Lessons Learned from the Planetary Decadal Survey
Speakers: Steven W. Squyres
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Scientific Discipline: Union

1:40 - 2:00pm PT - Overview of Key Results from the Exploration of the Pluto System by New Horizons
Speakers: S. Alan Stern
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2:00 - 2:16pm PT - New Horizons Investigation of Pluto's Small Satellites
Speakers: Harold A. Weaver, Jr.
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2:16 - 2:36pm PT - Geology of Pluto and Charon Overview
Speakers: Jeffrey M. Moore
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2:36 - 2:52pm PT - Pluto As Seen by the LEISA Spectrometer on New Horizons
Speakers: Dale P. Cruikshank
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2:52 - 3:08pm PT - Solar Wind Interaction with Pluto’s Escaping Atmosphere
Speakers: Fran Bagenal
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3:08 - 3:24pm PT - The Atmospheres of Pluto and Charon
Speakers: Randy Gladstone
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3:24 - 3:40pm PT - The Interacting Surface and Atmosphere of Pluto
Speakers: Leslie Ann Young
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Scientific Discipline: Volcanology, Geochemistry and Petrology

Speaker: Thomas W. Sisson

Abstract
The mainly igneous continents have intermediate mean SiO₂ (~60 wt%) and Mg# (0.4-0.55 mol). Bowen championed crystallization-differentiation of basalts to silicic daughter liquids, but he encountered difficulties with conflicting evidence for iron enrichment. We now know that as dry reduced basalts crystallize, melt SiO₂ begins climbing steeply at F (melt fraction): 0.25-0.35, reaching intermediate values at F: 0.1-0.2. H₂O changes basalt crystallization by (1) increasing the ratio of olivine to high-Ca pyroxene, (2) delaying onset and reducing the proportion of plagioclase, (3) stabilizing calcic plagioclase, (4) destabilizing low-Ca pyroxene, (5) eventually stabilizing amphibole, and (6) destabilizing silicate minerals more than magnetite. Factors 1-5 enrich melts early in SiO₂, 6 limits decline of Mg#. H₂O of 2-6 wt% is sufficient for early SiO₂ enrichment; fO₂ modestly above Ni-NiO yields daughter liquids with high (calc-alkaline) Mg#s. These values are matched by many natural subduction zone magmas, so seemingly, the problem is solved.

Yet, difficulties remain: Melt SiO₂ enrichment commences at F: 0.6-0.7 in experiments on hydrous Mg basalts, reaching intermediate SiO₂ at F: 0.2-0.4. Cumulates 60-80% of the basalt mass must have returned to the mantle if basalt differentiation formed the continents. Differentiation mainly near the base of the crust has geologic support, and would aid disposal of cumulates, but most experiments on hydrous basalts at such pressures yield peraluminous andesitic liquids, unlike common metaluminous andesites. A composite scenario avoiding peraluminous intermediates is crystallization-differentiation plus mixing with silicic liquids mainly residual or remelted from shortly antecedent intrusions. Even in this case, cumulates and restites exceeding the continental mass must have been lost. The Archean was different: Residual-eclogite-sourced granitoids are widespread, but experiments on hydrous eclogites at plausible temperatures yield melts with SiO₂ too high and Mg# too low. Reaction of such melts with peridotite is a likely solution, but must concur with the somewhat heavy oxygen in zircons from many Archean plutons. If the heavy oxygen derives from slab alteration, it provides a limiting measure of peridotite reaction.

Scientific Discipline: Volcanology, Geochemistry and Petrology

Speaker: Katharine V. Cashman

Abstract
Igneous petrology is undergoing a major paradigm shift. For the past century, the paradigm of the magma chamber - a single, melt-dominated magma body - has informed models of magma evolution and underpinned studies of volcanic processes. Over the past decade, however, the community has converted to a model of complex magma storage regions composed primarily of crystal-rich “mush”, with crystal-poor melt partitioned into sill-like lenses that can be tapped, either sequentially or simultaneously, to feed volcanic eruptions. Why has this conceptual shift occurred? Evidence for complex magma storage regions derives from numerous sources, including (1) geophysical evidence for sill-like melt bodies, (2) petrologic studies, which provide strong evidence that many erupted magma contain crystals that have been incorporated from different parts of the magma storage region, and over different time scales, and (3) geochemical evidence that magmatic gases may accumulate and be released independently from the melt. These observations suggest that magma storage regions are not only complex, but also dynamic, in that the solid (crystal), liquid (melt) and gas (exsolved volatiles) components may move and interact at different rates. Critically, adopting a melt-mush model requires a re-evaluation of processes responsible for melt segregation, evolution and eruption. For example, melt segregation and evolution may depend more on processes related to reactive flow of melts and fluids through porous crystal networks than sinking or floating of crystals within a (dominantly liquid) body. Additionally, patterns of eruptive behaviour may be determined as much by the stability of, and interactions between, individual melt lenses as by the evolution of a single melt body. From this perspective, studies of volcanic processes can be linked directly to processes of magma generation and evolution. Forging these links provides an exciting challenge for the future.