C51B-01 INVITED
Impacts of Declining Arctic Sea Ice: An International Challenge
As reported by the National Snow and Ice Data Center in late August of 2008, Arctic sea ice extent had already fallen to its second lowest level since regular monitoring began by satellite. As of this writing, we were closing in on the record minimum set in September of 2007. Summers may be free of sea ice by the year 2030. Recognition is growing that ice loss will have environmental impacts that may extend well beyond the Arctic. The Arctic Ocean will in turn become more accessible, not just to tourism and commercial shipping, but to exploitation of oil wealth at the bottom of the ocean. In recognition of growing accessibility and oil operations, the United States Coast Guard set up temporary bases this summer at Barrow and Prudhoe Bay, AK, from which they conducted operations to test their readiness and capabilities, such as for search and rescue. The Canadians have been busy showing a strong Arctic presence. In August, a German crew traversed the Northwest Passage from east to west in one of their icebreakers, the Polarstern. What are the major national and international research efforts focusing on the multifaceted problem of declining sea ice? What are the areas of intersection, and what is the state of collaboration? How could national and international collaboration be improved? This talk will review some of these issues.
C51B-02 INVITED
Causes of the Recent Arctic Warm Period within a Hundred Year Context
Arctic conditions in the recent decade are unique relative to those of the 20th century. From the loss of multi- year sea ice over the last two decades, the Arctic appears to be on a fast track for summer sea ice loss with current autumn temperature anomalies over the central Arctic of 5 C. This recent change is consistent with a combination of an emerging greenhouse gas contribution, a fortuitous sequence of warm years due to natural variability, and ice/ocean feedbacks. International collaboration has been central to obtaining these observations and synthesis. Current conditions were not anticipated from the expected value of anthropogenic climate change alone until 2050. Unlike the summer sea ice loss in 2007 which was supported by favorable winds, initial sea ice conditions were a primary loss factor for summer 2008 with implications for continued loss in future years. The major early 20th century Arctic warm event (~1925-1945) has been the subject of international scientific inquiry from the time it was detected in the 1920s and contrasts with recent conditions. Unlike the early 21st century, the 1930s event was not Arctic-wide. Much of the multiyear to interdecadal variability of surface air temperature (SAT) anomaly patterns in the 20th century is explained by a time-varying superposition of the AO/NAO, PNA, and a rare meridional wind pattern in the 1930s over northwestern Europe. The latter was important in the northern North Atlantic where Spitzbergen had winter decadal temperature anomalies of over 5 C. Longer instrumental records also indicate a centennial-scale warming across the North Atlantic. The fundamental cause of the early climatic fluctuation has never been unequivocally established, but intrinsic atmospheric variability coupled to ocean processes was an important factor relative to external forcing or hypothesized cyclic climate processes. Like today, the social and economic effects of the early event caused concern among scientists and the general public.
C51B-03 INVITED
SEARCH for DAMOCLES and Beyond: An International Approach to Studying the Changing Arctic
The Arctic system is presently changing at a rate never observed before. The changes are of pan-Arctic scale and affect the Arctic's physical, biogeochemical and human domains with complex interactions between them. Observing, understanding and responding to these environmental changes pose a significant challenge to the Arctic science community because they require projects and programs well beyond the scale of typical research efforts. For example, present efforts in building a pan-Arctic, cross-domain, long-term observing system heavily rely on stable international collaborations. As a response to this challenge new international partnerships are being formed and large programs are being coordinated and implemented. Here we discuss one example of a large international effort, SEARCH for DAMOCLES and describe its impacts on our capability to study Arctic environmental change.
C51B-04 INVITED
International collaboration in Arctic terrestrial research
The Arctic terrestrial region spans international borders in both North America and Eurasia, making internal collaboration essential to the monitoring and understanding of system-scale changes. Permafrost and hydrologic research in the Arctic are both benefiting from international coordination during the period of the International Polar Year. The Thermal State of Permafrost (TSP) is an IPY program that has mobilized researchers from more than 20 countries to make standardized temperature measurements in existing and new boreholes throughout the permafrost regions of both hemispheres. TSP builds on the Global Terrestrial Network on Permafrost (GTP-N), which includes the Circumarctic Active Layer Monitoring (CALM) project. This synoptic snapshot will provide a baseline for diagnoses of ongoing changes and assessments of future change on a pan-Arctic scale. Because permafrost changes affect hydrology, a relevant program is Arctic- HYDRA, for which the objectives include a characterization of the variability in the Arctic Hydrological Cycle (AHC), an examination of the linkages between atmospheric forcing and continental discharge to the ocean; and incorporation of hydrologic information into the attribution of recent variability of the Arctic system. Results presented here will focus on an assessment of the permafrost-hydrologic linkages as presently understood, with an emphasis on the key research needs to which programs such as TSP and Arctic-HYDRA can be brought to bear.
C51B-05
Sustaining Arctic Observing Networks: An International Initiative to Develop a Legacy to the International Polar Year (IPY)
The need for well-coordinated and sustained Arctic Observing Networks that meet scientific and societal
needs has been identified in various national and international reports. Both the Arctic Council (AC) and the
World Meteorological Organization (WMO) have called for creation of a coordinated set of Arctic Observing
Networks that meet identified societal needs.
In January 2007, the Sustaining Arctic Observing Networks Initiating Group (SAON IG), composed of
representatives of international organizations, agencies, and northern residents involved in research and
operational and local observing, was formed to undertake a process to respond to the AC and WMO
directives. With endorsement by the IPY International Program Office, the Swedish and Canadian IPY
Committees agreed to run a succession of workshops together with the SAON IG. Results from the
workshops are available at www.arcticobserving.org.
The communities represented in the workshops agreed with the SAON vision that users should have access
to free, open and high quality data that will realize pan-Arctic and global value-added services and provide
societal benefits. The objective of the SAON process is to provide a set of recommendations to achieve the
ultimate goal: to enhance Arctic-wide observing activities through coordination and integration and to
promote sharing and synthesis of data and information.
Implicit in this goal is recognition that most observing activities are now organized and implemented by
national or supra-national processes and that these processes are expected to continue for the foreseeable
future. Therefore the SAON goal focuses not on implementing observing activities, but on increasing their
value.
Workshop discussions noted that the IPY catalyzed formation of several internationally coordinated observing
networks, generally through 'bottom-up' processes. The more
successful of these can serve as 'building blocks' for a
sustained set of Arctic Observing Networks. Likewise it was recognized that the Arctic components of
networks established in a more 'top-down' way under the
auspices of organizations such as the WMO comprise an additional number of internationally coordinated
building blocks.
Workshop participants called for some type of international structure to tie together both the observing
activities and the decision-making processes regarding priority and funding. Yet there was a strong view
against establishment of new organizations and resource-requiring bureaucracies.
The recommendations in the final SAON report are being drafted at the time of preparation of this abstract. It
seems certain however those recommendations will include consideration of: the concept of
'building blocks' and how to build on them; coordination of the
various funding agencies and decision processes; use of web-based technologies for data and information
sharing; and a successor to the SAON-IG.
http://arcticobserving.org
C51B-06
Climate and Cryosphere (CliC) Project and update
The cryosphere is an important and dynamic component of the global climate system. The global cryosphere
is changing rapidly, with changes in the Polar Regions receiving particular attention during the International
Polar Year 2007-2008. The Climate and Cryosphere (CliC) Project is a core project of the World Climate
Research Programme (WCRP) and is co-sponsored by WCRP, SCAR (Scientific Committee for Antarctic
Research) and IASC (International Committee for Antarctic Research). The principal goal of CliC is to assess
and quantify the impacts that climatic variability and change have on components of the cryosphere and the
consequences of these impacts for the climate system. To achieve its objectives, CliC coordinates
international and regional projects, partners with other organizations in joint initiatives, and organizes panels
and working groups to lead and coordinate advanced research aimed at closing identified gaps in scientific
knowledge about climate and cryosphere. CliC has advanced significantly over the last several years. This
presentation will provide an update of recent developments of its research themes, highlighting regional
projects and their results, interaction and collaboration with other international projects, and outlining the
future direction of the CliC project.
http://clic.npolar.no/
C51B-07
Linking Ice Sheet Freshwater Discharge and Marine production in Greenland via Fiord Circulation. 'FreshLink', an Interdisciplinary Project Involving Researchers from Multiple Countries.
This interdisciplinary and international project has recently been initiated mainly with IPY funding from Denmark and Greenland. In short the project investigates the linkage between ice sheet freshwater release to a fiord near Nuuk (South-western Greenland) and the resulting fiord circulation. The low density melt water draining into the innermost of the long fiord forms a brackish outward sloping top layer, which exits the fiord and is balanced by entrance of nutritious salty oceanic water below. Such nutritious water, in turn, favors marine production in the fiord. The perspectives of a warmer climate, where more ice sheet melt water will increase the marine production, is of vital interest to investigate for the Greenland society because the present export from the country is totally dominated by living resources of the oceans. This interdisciplinary research project involves scientists from Greenland, Norway, Denmark and USA. Scientific disciplines presently covered are; marine ecology (biological production), cryospheric sciences (ice sheet and snow-water release), pollution chemistry (separating present from ancient precipitation), marine geology (history of freshwater input), oceanography (fiord circulation), geodesy (cryospheric elevation changes), and hydrology (land runoff). First field results will be presented together with the perspectives for linking each fresh water component coming from land and ice to the observed freshwater budget in the fiord.
C51B-08
Variability and mechanisms of the Antarctic sea ice: Why the Antarctic sea ice is not decreasing like its northern counterpart
Satellite passive microwave data been used for about three decades to provide information of the polar sea ice coverage. In contrast to the Arctic sea ice, which shows a dramatic and very public reduction in sea ice cover, the trend in the Antarctic sea ice cover is slightly increasing. Precipitation is expected to increase substantially over the polar regions with increased greenhouse warming. This has important implications for the, generally weak, stability of the upper layers of the Southern Ocean as well as for the snow cover on top the sea ice. The talk will give an overview of the observed changes in the Antarctic sea ice cover and will discuss processes and mechanisms that can explain the observed asymmetry.