SEARCH at AGU Fall Meeting 2018

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SEARCH Town Hall

Where Does Arctic Research and SEARCH Go Next?

Date/Time: Friday, 14 December 2018 | 12:30-13:30
Locations: Marriott Marquis - Independence D
AGU Program Link: https://agu.confex.com/agu/fm18/meetingapp.cgi/Session/55416

Over the next year, SEARCH is seeking input on future activities that will advance Arctic science in ways that increase our understanding of the system and inform decision making. Please consider participating in our town hall, “Where Does Arctic Research and SEARCH Go Next?” at the Fall meeting of the American Geophysical Union, 10 – 14 December 2018. The town hall will explore with interested scientists where the program has provided benefit and—more importantly—where it could do so in the future. How can the Arctic research community best advance actionable and discovery science? What could or should a multi-disciplinary effort accomplish that otherwise would not get done? Whether or not you participate in the town hall, please contact Brendan Kelly with thoughts about SEARCH and the future of Arctic research.

Sessions Convened by SEARCH Affiliates

Glacier Processes from Large-Scale Remote Sensing

C11C: Posters
Date/Time: Monday, 10 December 2018 | 08:00-12:00
Location: Convention Ctr - Hall A-C (Poster Hall)
C14A: Presentations
Date/Time: Monday 2018 | 16:00-18:00
Location: Convention Ctr - Salon H
Description: In glaciology, as in many fields, the rate of data production has reached a pace that often exceeds the rate of insight generation. A wide array of earth-observing satellites allow scientists to investigate glacier processes over larger spatial scales at higher temporal resolution than ever before. However, extracting process understanding from this rich data record remains a challenge. Deeper understanding of glacier processes is critical for accurately assessing and predicting current and future glacier change and associated downstream impacts. In this session, we seek studies that exploit the wealth of remote sensing data to increase our understanding of glacier processes, including: basal motion, calving, grounding line migration, elevation change, ice flow, surging, and mass balance. We particularly seek large spatial and/or temporal scale studies that characterize process variability and its controlling physical factors. We also solicit studies using innovative analysis techniques, such as cross-sensor approaches, machine learning, and modeling-aided interpretation.
Conveners: William Armstrong, Twila Moon, Bas Altena, Amaury Dehecq

Vulnerability of Permafrost Carbon to Climate Change

B22D: Presentations
Date/Time: Tuesday, 11 December 2018 | 10:20 - 12:20
Location: Convention Ctr - 143A-C
B31E: Posters
Date/Time Wednesday, 12 December 2018 | 8:00 -12:20**
Location: Convention Center - Hall A-C (Poster Hall)
Description: Permafrost zone soils contain 1330-1580 Pg of organic carbon (C). Permafrost degradation can decrease ecosystem C storage by enhancing microbial activity and ecosystem respiration, but can also stimulate plant growth and lateral C flux, potentially increasing C stored in vegetation, soil, and sediment. This session invites papers that examine factors causing losses and gains in ecosystem C storage that relate to the question: What is the magnitude, timing, and form of C release from permafrost zone ecosystems to the atmosphere in a changing climate? Papers may address any aspect of this topic from molecular to global scales, using measurements or modeling to detect or forecast permafrost thaw and its influence on the C cycle and climate.
Conveners: Christina Schaedel, Jessica Ernakovich, and Ted Schuur

Integrating Observations and Models to Better Understand a Changing Arctic System

C32B: Presentations
Date/Time: Wednesday, 12 December 2018 | 10:20 - 12:20
Location: Convention Ctr - Salon G
C33F: Posters
Date/Time: Wednesday, 12 December 2018 | 13:40 - 18:00
Location: Convention Ctr - Hall A-C (Poster Hall)
Description: The Arctic environment is changing at an unprecedented rate. There is a significant need to understand ongoing Arctic system change and predict its future behavior. Model studies play a fundamental role in these tasks as a tool for experimentation and prediction. However, progress in model development often suffers from a disconnect with discoveries made in the observational community. In turn, observational activities could make better use of model guidance regarding the relative importance of various processes and improved sampling strategies. This session welcomes presentations that integrate in situ observations and remote sensing data with Arctic modeling activities to enhance the understanding of the changing Arctic system. Examples of this integration include methods to use observations in model validation and improvement, observational network design that use models to guide observations, and data assimilation activities which combine models and observations to enhance understanding and prediction of the Arctic system.
Conveners: Marika M. Holland, Jennifer E. Kay, Donald K. Perovich

Putting Arctic Science to Work: Using Your Words to Reach Collaborators and Decision-makers

C33E: Posters
Date/Time: Wednesday, 12 December 2018 | 13:40-18:00
Location: Convention Center - Hall A-C (Poster Hall)
Description: The Arctic is changing more rapidly than other parts of the planet with broad impacts on ecosystems, sea level, global weather patterns, transportation, and geopolitics. Responding to these intertwined changes requires collaboration across disciplines and effective communication with decision makers. The Interagency Arctic Research Policy Committee uses an open platform, IARPC Collaborations, to enhance communication, coordination, and collaboration between researchers of various disciplines and other stakeholders. The Study of Environmental Arctic Change developed expert-authored two-page briefs to answer policy-relevant science questions and promote cross disciplinary studies. The effectiveness of these and similar models depends on understanding different audiences, especially non-scientific and interdisciplinary audiences, and communicating accordingly. This session invites presentations that illustrate communication that is effective for promoting new collaborations and/or for conveying scientific understanding to decision-makers.
Conveners: Jessica Anne Rohde and Brendan P. Kelly

Arctic Geohealth: Climate Change and Health Impacts in Northern High Latitudes

GH43A: Posters
Date/Time: Thursday, 13 December 2018 | 13:40 - 18:00
Location: Convention Ctr - Hall A-C (Poster Hall)
Description: Rates of climatic, cryospheric, and ecological change in the Arctic and Boreal regions are faster than the global average, and consequences for often remote Arctic communities range from disruption of traditional and historical seasonal timing of activities to complete relocation of vulnerable communities. Specific effects on public health in these communities include permafrost-related impacts on infrastructure, food safety, respiratory effects of increased wildfire smoke, and many others. We invite contributions describing the mechanisms by which high latitude climate changes impact community and individual health around the planet, the nature of those impacts, their consequences, and the potential for adaptation given identified vulnerabilities. We also encourage approaches to synthesis of indigenous knowledge and western science that may increase capacity to deal with the nature and impacts of these stressors.
Conveners: Brendan M. Rogers, Sandra Starkweather, Stephen T. Gray

Presentations by SEARCH Affiliates

Asynchronous response to late Holocene cooling by glaciers in the Atlantic and Pacific sectors of the Arctic explained by weakening AMOC and intensified Aleutian Low: a data-model comparison

PP11B-07: Presentation
Date/Time: Monday, 10 December 2018 | 9:45 - 10:00
Location:Convention Ctr - Salon I
Description: Reconstructions of equilibrium line altitude (ELA) changes for the Eastern Canadian Arctic, West Greenland, Iceland and Svalbard document an ELA drop over the past 2 ka of ~200 m, and as much as 500 m since 5 ka. In contrast, ELA depression in the Brooks Range of Alaska was only ~50 m, and the pollen record of Alaska climate change since 6 ka is small. Change in surface air temperature between 1-1000 CE and 1000-1850 CE for 30 PAGES2k Arctic sites show a similar asymmetry between the Atlantic and Pacific Arctic, despite hemispherically symmetric orbitally-paced insolation forcing. The lack of a geographically specific forcing that might explain the observed asymmetries led us to evaluate potential Northern Hemisphere circulation changes in response to symmetric forcing. We did this by completing the first fully coupled 2 ka transient simulation using the CESM1 at 1°resolution (ocean and sea ice) and 2°resolution (atmosphere and land) with forcing data from PMIP4, including changes due to insolation, volcanic aerosols, land cover and GHG. Because insolation-driven Arctic cooling over the past 2 ka is enhanced by surface albedo feedbacks (SAF), we evaluated SAF separately for Atlantic and Pacific sectors of the Arctic. We found that the SAF is slightly stronger in the Pacific than Atlantic Arctic, hence cannot explain the observed asynchronous response. However, we found that the Atlantic Arctic cooled by ~0.19°C between the past two millennia in the CESM, considerably larger than the 0.04 (winter) and 0.12°C (summer) cooling for the Pacific Arctic. The Atlantic cooling was enhanced due to a weakening of the AMOC by ~1 Sv between the two millennia, reducing the northward heat transport by 0.03 PWatt at 26 °N and by 0.01 PWatt at 60 °N. At the same time, insolation-driven cooling in the Pacific sector was countered by a strengthened Aleutian Low during winter, with >2 m depression in the 850-hPa geopotential height. This led to warmer winters around the Bering Sea, as storm systems preferentially pump warm air poleward. The observed dynamic response to symmetric forcing over the past 2000 years may have been effective throughout the entire Holocene, resulting in consistently stronger Atlantic Arctic responses to hemispherically symmetric forcing than for the Pacific sector, explaining the observed discrepancies in ELA changes.
Authors: Gifford H. Miller, Yafang Zhong, Alexandra Jahn, Áslaug Geirsdóttir, Jason P. Briner, Avriel D. Schweinsberg

Greenland freshwater production and the iceberg environment

C13A-01: Presentation
Date/Time: Monday, 10 December 2018 | 13:40-13:55
Location: Convention Ctr - Salon H
Description: Greenland freshwater production is increasing via greater surface melt and melt of discharged solid ice. We tie together recent research looking at detailed spatiotemporal freshwater fluxes and separately at the potential use of freshwater-producing glacial environments by narwhal whales (Monodon monoceros). Focused research in the Sermilik Fjord – Helheim Glacier system demonstrates that iceberg melt can dominate the freshwater production budget annually, with spatial and temporal freshwater production that is also distinct from other sources. Furthermore, 40-100% (depending on season) of iceberg melt produced at depth is likely to remain at depth, an important difference from how freshwater fluxes are commonly treated in many ocean models and potentially a critical ecosystem characteristic. For example, freshwater produced from solid ice melt, both at the glacier terminus and from icebergs, may be a key environmental factor influencing narwhal whale glacial environment use. Data from 15 whales and 41 marine-terminating glaciers in Melville Bay, West Greenland, suggest that narwhals prefer glaciers with potential for higher ambient freshwater melt, such as that from the ice front and icebergs, over glaciers with silt-laden discharge. Ongoing improvements in understanding both the physical processes of freshwater production and biological freshwater dependence will help to constrain future effects of continued Greenland ice sheet evolution and ice loss on local to ice-sheet-wide scales.
Authors: Twila Moon, David A. Sutherland, Kristin Liisa Laidre

Permafrost Carbon Network: Synthesis Science and Outreach

PA23F-2995: Poster
Date/Time: Tuesday, 11 December 2018 | 13:40-18:00
Location: Convention Center - Hall A-C (Poster Hall)
Description:The Permafrost Carbon Network (PCN, www.permafrostcarbon.org) is a US sponsored but international network that produces new knowledge through research synthesis quantifying the role of permafrost carbon in driving future climate change. Established in 2010 with initial funding from the National Science Foundation (NSF) Research Coordination Network program, the PCN is a hub for synthesizing emerging data from individual projects, across a range of new measurement programs, and providing updated parameters in support of model assessment and development. PCN activities continued with the same focus in 2015 under the umbrella of the NSF Study of Environmental Arctic Change Program, which itself has a broader focus of the Arctic as a system. Within eight years, the network has grown from 45 scientists to 380 members from 155 institutions and 24 countries. One of the key elements for the high success rate in producing high profile publications within the activities of the PCN is the pairing of early career scientists with more senior scientists. This model creates career opportunities for early career scientists that are motivated for the detail oriented work such as data mining and analysis and provides the expertise from senior scientists that is necessary for the big picture understanding. Member interaction and opportunities for brainstorming occur during a one day open science meeting organized by the PCN the day before the fall meeting of the American Geophysical Union, which has attracted over 100 scientists interested and engaged in synthesis activities. Synthesis science results are published in peer-reviewed literature, presented at national and international meetings and incorporated into global scale reports such as the Intergovernmental Panel on Climate Change in order to disseminate results to a non-export audience. Synthesis information created by the PCN also provides a platform for communicating science results to society via news articles, blog posts, and via online communication, which are all meant to increase science impact to non-experts.
Authors:Christina Schaedel, Ted Schuur

Lessons from the Arctic Observing Framework for Sea Ice Forecasting - A Task of the US Arctic Observing Network (US AON)

A24K-03 - Lightning Talk
Date/Time: Tuesday, 11 December 2018 | 16:07 - 16:10
Location: Convention Ctr - eLightning Theater I
Description: The Arctic is experiencing significant system-wide change particularly across the cryosphere and ice-dependent ecosystems. Timely, reliable, and coherent information on these conditions is urgently needed by decision makers. At present, U.S. and international observational assets – critical to tracking these changes - are woefully sparse, lacking a shared vision about key observing targets, and subject to ad hoc support. In response to these challenges, National Oceanic and Atmospheric Administration (NOAA) leadership initiated US AON to work across agencies and with international partners to improve coordination. Over the past year, US AON has been exploring the role of observing frameworks for addressing these challenges. The objectives of which include: 1) clarifying the user base for observing systems and their product/service/information needs; 2) identifying barriers to the efficient exploitation of current observing systems to meet those needs; and 3) improving readiness for future observing systems. In reviewing systems architectures that might support these objectives across the ‘system of observing systems’, US AON has provisionally adopted the approach of the Framework for Ocean Observing (FOO). One appeal of which is that many elements for an Arctic realization are already in place. For example, a societal benefit framework was developed in 2017 that could be used to assess key observing targets. To test the value of the FOO and the societal benefit framework, a learning exercise was conducted through the US AON Sea Ice Forecasting Task Team to develop a comprehensive, end-to-end mapping of the observing system components needed to support current and future sea ice forecasting needs. This effort illustrates the dependencies between dozens of satellite systems and in situ platforms, how they currently support the key forecasting activities, and in turn how these forecasts and analyses support operational ice services and research needs. We will report out on the lessons learned in applying this model towards our stated objectives. Early results show that such an approach is exceptional at illustrating dependencies and vulnerabilities in the observing system but needs greater definition under the societal benefit areas to sharpen the requirements for the future observing system.
Authors: Sandra Starkweather, Janet M. Intrieri, Amy Solomon, Sinéad Louise Farrell, John Woods

Exploring the Cryosphere from the Air and Space: The Power of Perspective

C24A-02: Presentation
Date/Time: Tuesday, 11 December 2018 | 16:20 - 16:40
Description: Throughout history, humans have always valued the view from above, seeking high ground to survey the land, find food, assess threats, and understand their immediate environment. The advent of aircraft early in the 20th century took this capability literally to new levels, and since the launch of the first weather satellite in 1960, we have come to know our world in ways that were not possible before, as we saw the Earth as a system of interacting components. Airborne and space-based observations have been particularly transformational in advancing our understanding of the cryosphere and its interactions with the rest of the planet. They have allowed us to observe the cryosphere in new ways, making the distant, vast, and remote much more accessible. The power of this perspective, and the associated advances in our ability to analyze Cryospheric processes, have enabled both incremental and transformational advances in our understanding of their behavior and their interactions with the rest of the Earth System. This knowledge and these capabilities have allowed us to answer questions that were once thought unanswerable and explore new questions that help us understand the current state and potential future of these rapidly-changing components of the Earth System.
Author: Waleed Abdalati

Arctic Indigenous Peoples Perspectives on Enhancing an Arctic Observing Framework

A24K-19: Lightning Talk
Date/Time: Tuesday, 11 December 2018 | 16:55 - 16:58
Location: Convention Ctr - eLightning Theater I
Description: The Arctic is changing at an accelerated rate due to climate change and increased anthropogenic activity. Given the rate of change, never has it been more important to work toward a complete understanding of the Arctic’s interconnecting systems. Arctic Indigenous Peoples have always made observations of and monitored change, providing a holistic understanding across biological, physical and social systems. To further understand how an observing framework might take an equitable approach, it is important to acknowledge that the practice of observation systems has occurred for millennia. Understanding ones environment and observing changes has been a matter of survival and directly related to the maintenance of food security. Both scientific and Indigenous Knowledge monitoring methodologies are important. It is crucial to fully understand each and what types of questions each approach is able to address. A co-production of knowledge framework can provide the holistic view and comprehension needed. We underscore the role and value of different knowledge systems with different methodologies and the need for collaborative approaches in identifying developing observing systems that effectively cross scales. In this presentation we will share our perspective in working towards strengthening Arctic Observing Systems that include an underlying framework equitably informed by Indigenous Knowledge.
Authors Raychelle Daniel, Carolina Behe, Lene Kielsen Holm, Eva Kruemmel, Julie Raymond-Yakoubian

Connecting People, Infrastructure and Permafrost Information in Alaska

GC31B-02: Presentation
Date/Time: Wednesday, 12 December 2018 | 08:15-8:30
Location: Convention Ctr - Salon A
**Description:
Infrastructure planning and design currently incorporates the concept of permafrost as ground that is frozen continuously for two or more years, using many different techniques and types of data. However, this basic definition does not include ice content or the roles water, surface topography and vegetation play in modifying the ground thermal regimes governing permafrost. For example, surface water in permafrost areas covered a total area of 1,066,643 ± 144,582km2 in the northern hemisphere where lands approximately size of the state of New York converted from land to water or vice versa between 1985 and 2015. Planning and building infrastructure on permafrost requires synthesizing data including this type of information on surface water to better understand the pre-disturbance conditions, impacts the infrastructure will have, and how to best mitigate potential issues. Data supporting this analysis is produced through a variety of different lenses, with features including spatial (building site vs. community vs. regional vs. statewide vs. global), temporal (long-term monitoring vs. project based), accessibility (data collected by a public agency that should be open and easily accessible vs. data collected by private parties and industry), type (point collection vs. distributed grids). The data collection process is already well-established for conducting site-level analysis using historical data products for planning and building some types of infrastructure. However, this often fails to consider future changes or data sparseness. This project examines theoretical vs actual data availability for permafrost and infrastructure information critical for planning and development in Alaska. We explore proof-of-concept methods of quantifying environmental change related to permafrost conditions around infrastructure. We also identify key areas which contain critical information gaps for assessing permafrost related impacts to infrastructure. This analysis will highlight the development of a framework that connects permafrost specific information to infrastructure risks within the context of project planning and decision making. It will enable the research community to better position their products to fit the needs of stakeholders and improve interfaces for dissemination.
Authors: Erin Trochim, Edward Schuur, Scott T. Rupp, Alec Bennett

Science of a Rapidly Changing Arctic System

TT32A: Presentation
Date/Time: Wednesday, 12 December 2018 | 10:20 - 10:50
Location: Marriott Marquis - University of DC/Catholic University
Description:The Arctic system is changing rapidly. Melting land and sea ice, thawing permafrost, atmospheric extremes, warming oceans, and terrestrial landscape changes have already created a new Arctic “normal”. Dramatic future changes are expected, with significant consequences locally and globally. Based on the science and discussion shared at an NSF Arctic System Science Workshop (held April 2018 at the National Center for Atmospheric Research), this tutorial will overview the connected physical systems of the Arctic, discuss its recent evolution as the most rapidly warming region on the planet, and highlight the next frontier in Arctic system science. This includes developing new partnerships across observational and modeling efforts, focusing on interdisciplinary boundary regions between Arctic system components, exploring the feedbacks of increasingly common extreme events, and preparing research to understand the impacts of moving from an ice-dominated system to a water-dominated system. We can expect the Arctic to continue to warm at more than twice the rate of the planet as a whole, and we need all hands on deck to understand the consequences across this difficult-to-study region. This tutorial will bring scientists, stakeholders, and the interested public up to date.
Presenters: Twila Moon, Marika Holland

A Stakeholder analysis for Arctic sea ice loss: Defining the opportunity for usable science

PA43F-3256: Poster
Date/Time: Thursday, 13 December 2018 | 13:40-18:00
Location: Convention Center - Hall A-C (Poster Hall)
Description: Arctic sea ice loss is one of the most visible signs of global environmental change and is both reshaping northern human-environmental systems and increasing the potential for an expanding human footprint in the Arctic. While ice extent and volume decline at dramatic rates and we approach a mostly ice-free Arctic by as early as mid-century, there is increasing interest in providing relevant science to policymakers, accurate forecasts to those operating in Arctic waters, and realistic scenarios to planners exploring adaptation options. Furthermore, there are growing prospects for research to partner with the private sector. This presentation will provide a stakeholder analysis for Arctic sea ice loss as a means to illuminate the full range of its societal implications and to define the opportunity space for usable science to inform decision-makers. Stakeholder analysis is a deliberate process of identifying and characterizing individuals, groups, and organizations that have a vested interest in a topic. Stakeholder analysis has long-served as a practice by the private sector to identify those affected by business decisions, and by policy analysts who strive to improve and enhance the credibility, salience, and legitimacy of policymaking. More recently, stakeholders are also seen as belonging to an “issue network”, where they introduce resources, opportunities, values, or grievances in relation to a specific topic. As such, Arctic sea ice stakeholders include those with a relationship to either the ecosystem services (or disservices) associated with Arctic sea ice or its rapid decline. Drawing on scientific literature, trade journals, news articles, and expert interviews, this analysis systematically identifies and characterizes stakeholders according to their interests, sector, level of influence and coordination, and reliance on decision-support tools.
Author: Matthew L. Druckenmiller

Arctic and Boreal Carbon: Key Findings from the State of Carbon Cycle Report

B43C-08: Presentation
Date/Time: Thursday, 13 December 2018 | 14:16 - 14:23
Location: Convention Ctr - 150A
Description: Factors that control terrestrial carbon storage in unmanaged arctic and boreal ecosystems are changing. Surface air temperature change is amplified in high-latitude regions, as seen in the Arctic where temperature rise is about 2.5 times faster than that for the whole Earth. Permafrost temperatures have been increasing over the last 40 years. Disturbance by fire (particularly fire frequency and extreme fire years) is higher now than in the middle of the last century. Soils in the northern circumpolar permafrost zone store 1,460 to 1,600 petagrams of organic carbon (Pg C), almost twice the amount contained in the atmosphere and about an order of magnitude more carbon than contained in plant biomass (55 Pg C), woody debris (16 Pg C), and litter (29 Pg C) in the boreal forest and tundra biome combined. This large permafrost zone soil carbon pool has accumulated over hundreds to thousands of years, and there are additional reservoirs in subsea permafrost and regions of deep sediments that are not added to this estimate because of data scarcity. Following the current trajectory of global and Arctic warming, 5% to 15% of the organic soil carbon stored in the northern circumpolar permafrost zone (mean 10% value equal to 146 to 160 Pg C) is considered vulnerable to release to the atmosphere by the year 2100. However, a recent model intercomparison project suggested that additional plant carbon uptake, growth, and deposition of new carbon into soil would together completely offset any soil carbon loss this century, and that it would take several centuries before cumulative losses from soils would overwhelm new carbon uptake. However, model projections do not always match current empirical measurements or other assessments, suggesting that structural features of many models are still limited in representing Arctic and boreal zone processes. At the same time, the intercomparison indicated that future scenarios with limited human greenhouse gas emissions would reduce changes to high latitude ecosystems. Together, the loss of carbon from thawing permafrost soils and disturbance by fire in combination with offsetting plant uptake response determines the net effect of high latitudes on the carbon cycle of both North America and the globe.
Authors: Edward Schuur, Anthony David McGuire, Vladimir E. Romanovsky

How Changing Fluvio-deltaic Systems Affect Permafrost

EP52B-03: Presentation
Date/Time: Friday, 14 December 2018 | 10:50 - 11:05
Location: Convention Ctr - 147A
Description: Arctic climate warming impacts the terrestrial hydrological system by decreasing snow cover duration, melting glaciers and by permafrost thaw. Observations indicate river discharge is increasing and the timing of peak floods has shifted. How do these profound changes in river systems impact permafrost dynamics? And vice versa, how does thawing permafrost control river morphodynamics? To assess whether river flood dynamics impact permafrost temperature and active layer thickness evolution in floodplains and riverbanks, we combine remote-sensing data analysis and numerical models of permafrost dynamics with river and delta process models. We calculate permafrost temperature evolution with the Control Volume Permafrost Model (CVPM), which implements the non-linear heat transfer equations in multiple dimensions. CVPM is designed to account for a large variety of materials, a.o. organic rich material, fine-grained material, sand and gravel – and thus allows for experiments with varying floodplain stratigraphy. We define hypothetical floodplain cross sections in the upstream and downstream regions. Analyses of remotely-sensed Landsat8 imagery is used in combination with a river discharge and temperature model, driven by annual relationships of solar radiation and cloudiness. This river model provides the permafrost model with varying river flood extents, depths, durations and temperature. Simulations are set to be representative for conditions in the continuous permafrost zone, such as rivers and deltas on the Arctic coastal plain of Alaska. Our simulations show that permafrost active layer thickness deepens significantly in response to prolonged flood inundation. Consequently, the lowest-lying sections in the floodplain that experience the longest flood durations would consistently have deeper active layers. The thawing effect is more pronounced for early season floods, whereas it takes time for heat to transfer into already thawed soils if floods occur later in the summer. We hypothesize these effects on permafrost dynamics could potentially have ramifications for permafrost bank erosion as well. Enhancing our understanding of how permafrost thaw is impacted by rivers ultimately improves predictions of release of old stocks of carbon, which is one of great questions about the changing Arctic.
Authors: Irina Overeem, Lei Zheng, Gary Clow, Kang Wang

The relationship between changing sea ice and surface air temperature in the Arctic

A52B-08: Presentation
Date/Time: Friday, 14 December 2018 | 12:05-12:20
Location: Convention Ctr - 152A
Description: All climate models project loss of sea ice and amplified Arctic warming in response to rising greenhouse gas concentrations. However, the magnitude, spatial structure, and seasonality of the ice and air temperature response differs among models. Here we use Community Earth System Model simulations to explore relationships between changes in sea ice conditions, surface heat budgets and atmospheric temperature in order to identify some of the controlling factors on the Arctic response to a changing climate. We find that there is a seasonal dependence on the aspects of sea ice change that are related to the changing surface heat budgets, with implications for the Arctic surface air temperature response. Because of non-linearities in the relationship to changing sea ice conditions, the mean state from which change occurs can play an important role in the transient Arctic response. This has implications for the factors that drive across-model scatter in the Arctic amplification response.
Authors: Marika M. Holland, Laura Landrum

An assessment of arctic observing based on the historically low sea ice coverage of the Bering Sea in winter 2017-8

OS53B-02: Presentation
Date/Time: Friday, 14 December 2018 | 13:55 - 14:10
Location: Convention Ctr - 101
Description: During the winter of 2017-18, the Bering Sea experienced the lowest sea ice extent observed since the 1850s. The combination of low pack ice concentration, minimal or absent shorefast ice, and winter storm activity caused coastal damage in several Bering Sea communities. At the same time, the unusual conditions have raised key questions regarding the impact on migratory species and marine productivity. This record-setting season provides an opportunity to assess the state of sustained observations of rapid Arctic change at the regional level. Of particular importance is the availability of data relevant to evaluate and respond to impacts of changing ocean, atmosphere, ice, and coastal conditions on local communities and marine mammals. This presentation will summarize an ongoing effort to use the International Arctic Observations Assessment Framework to evaluate knowledge and operational gaps related to disaster preparedness, maintaining critical infrastructure, food security, marine ecosystems, and our fundamental understanding of Arctic environmental change. An observing system is intended to sustain and coordinate observations in ways that increase understanding of environmental change, improve predictive abilities, and inform adaptive responses to change. This assessment aims to identify the additional infrastructure, instrumentation, observations, data sources, and information-sharing platforms that may maximize capacity to understand and respond to a potentially new winter ice regime in the Bering Sea region. In doing so, this research is intended as a regional contribution toward advancing a pan-Arctic observing system’s societal benefits related to environmental, economic, security, and cultural concerns.
Authors: Matthew L. Druckenmiller, Hajo Eicken, Jennifer Ann Francis, Henry Huntington, Olivia Lee

Other SEARCH Affiliated Events

8th Annual Meeting of the Permafrost Carbon Network

Permafrost Carbon Network Logo
WS31: 8th Annual Meeting of the Permafrost Carbon Network
Date/Time: Sunday, 9 December 2018 | 8:00 -16:00
Location: Grand Hyatt - Independence FGHI
Description: The 8th Annual Meeting of the Permafrost Carbon Network (PCN) is an open science meeting that brings together more than 100 scientists from the US, Europe, and Asia. The PCN produces new knowledge through research synthesis and links terrestrial ecosystems (boreal forest, tundra, and peatlands) with the cryosphere. During the Annual Meeting, short scientific presentations about individual syntheses will inform the community about where the science stands and where it is headed while breakout discussions actively involve meeting participants in topics that are related to permafrost carbon and the consequences to the global system. Many of the synthesis leads are early or mid-career scientists and the Annual Meeting is a unique opportunity to receive direct feedback from the research community.

Download a preliminary agenda here.

If you are interested in participating, please contact Christina Schädel at 928-523-9588 or christina.schaedel [at] nau.edu.

IASC Town Hall

IASC Logo
TH15K - U.S. International Science Committee (IASC) Town Hall: An Overview and Discussion on IASC Research, Engagement Activities, and Associated Opportunities
Date/Time: Monday, 10 December 2018 | 18:15 - 19:15
Location: Marriott Marquis - Archives
Description: The U.S. Delegation to the International Arctic Science Committee (IASC) invites AGU participants to a town hall forum that will provide an overview of IASC and its activities. IASC is a non-governmental organization that encourages, facilitates, and promotes international cooperation and knowledge exchange in all aspects of Arctic research. We will provide an introduction to how IASC functions, deliver an overview of the five Working Groups’ activities, and discuss the value and opportunities for scientists to connect with IASC, including the IASC Fellowship for early career scientists. Additionally, short presentations will be provided on select IASC supported activities, including the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC), which will be the first year-round expedition into the central Arctic to explore the Arctic climate system, the new and developing terrestrial version of MOSAiC (T-MOSAiC), the Rapid Arctic Transitions due to Infrastructure and Climate (RATIC) project to address the cumulative effects of Arctic infrastructure and climate change, and the ALaskan Pollution and Chemical Analysis (ALPACA) project to advance understanding of the atmospheric chemistry responsible for winter air pollution. This event is open to anyone interested in the Arctic and, in particular, international collaboration, observing systems, and science’s engagement with decision-makers and society.
Convener: Matthew L. Druckenmiller