ARCSS Program | Co-oP Concept Paper Submissions by Question

Question 5

Lilian Na'ia Alessa
A variety of changes have been identified in the Arctic System. Changes in the availability of freshwater at local and regional scales will have the most direct and immediate impact on humans and their antecedent activities. A common component of existing programs is the characterization of changes in multiple venues (e.g., earth surface, sea ice, etc). We suggest that while many of these changes (e.g., vegetation) of the Arctic are profound, they are occurring on temporal scales that allow slightly more time to adapt. However, changes in the hydrological cycle may be sudden and acute resulting in unpredicted emergent patterns. We propose the formation of a research community whose goal is to undertake the integrated study of local scale changes in hydrology, particularly as they interact with and affect biological communities in the Arctic system, including but not limited to, humans. There exist substantial Bodies of Knowledge from which we can conclude that changes in both the land and ocean surface will establish complex feedback cycles in Arctic hydrology. We propose to pursue an understanding of the interactions between these variables in order better understand how freshwater links and affects critical processes in the Arctic.

Thomas Douglas
Atmospheric contaminants follow complex routes to the Arctic before they are deposited onto ecosystem receptors and undergo biological transformation and uptake. Atmospheric processes that promote deposition are wide ranging and are often unique to each contaminant. Processes include photochemical reactions, active halogen chemistry, and aerosol surface heterogeneous chemistry to name a few. Many of the chemical components entering the Arctic terrestrial regime biomagnify in foodwebs after they are deposited to sea ice, snow, water, vegetation or soils. Native peoples and predators at high trophic levels are thus at risk for incorporating contaminants into their diet at many times the concentration initially deposited onto the landscape.

Arctic ecosystems are unique because of the dramatic seasonal variations in sunlight, temperature, moisture content and biological activity. Ongoing environmental change in the Arctic will likely modify surface temperature, sea ice extent, and precipitation. These changes may have a marked effect on fluxes of atmospheric chemical components both to and within the Arctic, but the potential responses of Arctic systems to these changes is not well understood. In addition, the emission rates of many chemical components that migrate to the Arctic are likely to increase in the future, especially from major sources in Asia and Western Europe. The reaction of the Arctic system to a combination of warming and changing atmospheric inputs is unknown.

Addressing the scientific questions given above will require multidisciplinary investigations to formulate a system-level understanding of how the Arctic receives, takes up, transforms, and stores atmospheric chemicals. A multi-chemical species approach is particularly illuminating because each chemical component has a different atmospheric chemistry, depositional regime, soil storage capacity and biological uptake regime. By tracking the deposition and storage pathways of selected chemical components in the Arctic system we can learn more about primary system processes and their responses to system changes.

Ivan Eyefor Watts
1) To synthesize information from the wealth of Arctic data already available in a tractable energy budget framework to better assess linkages between key Arctic system components.
2) To provide a common framework within which existing data streams and information from new efforts can be ingested to better monitor variability and change in the Arctic system.
3) To enable more effective partnerships between modeling and observational communities, leading to better understanding of climate system feedbacks.

Fitting in with ARCSS: The emerging new ARCSS structure emphasizes viewing the Arctic as an integrated system. Arguably the most integrating component of the Arctic system is its climate system. The mean state, variability and change in the climate system exerts strong controls on biological processes and human activities. The energy budget offers a tractable, yet physically robust framework to understand the relative importance of different component processes and interactions that shape the present and likely future state of the Arctic. Past ARCSS efforts, programs within NASA, NOAA and the wider international community, have assembled a wealth of diverse data sets relevant to understanding how the Arctic functions. This includes information from atmosphere reanalyses, data-driven coupled ice-ocean models, coupled global climate models, satellite remote sensing, long-term surface observing networks and intensive field programs. Our evolving Community of Practice (CoP) recognizes that synthesizing information from these diverse sources in an energy budget framework will represent a tractable, physically-based approach to help us better assess interactions between the atmosphere, land surface, ocean and lower-latitude forcings that shape the Arctic climate system. By ingesting data from past and future ARCSS field efforts and by fostering synergy between models and observations, this framework will foster more effective collaboration between different elements of the ARCSS community.

Kenneth Hinkel
Thaw lakes constitute a type of thermokarst terrain and represent the effect of permafrost thaw and ground subsidence at the surface. In landscapes where thaw lakes are the dominant geomorphic feature, lakes represent the quasi-equilibrium response to regional or global climate forcing that impacts the entire landscape. Lakes, in turn, alter the thermal regime of the underlying permafrost. As the ground thaws and subsides, lake basins deepen and expand. Following eventual drainage, DTLBs and peatlands are sites for preferential accumulation of soil organic carbon which has the potential to amplify warming if stored carbon becomes mobilized to the atmosphere as greenhouse gases. Owing to their prevalence, extent and properties, a deeper understanding of arctic lake and DTLB dynamics is required to assess the future state of the earth system.

Recent studies by members of this CoP have demonstrated that there has been an increase in the number of lakes by 4% and a concurrent increase in total lake area by 12% in the continuous permafrost zone of western Siberia over the period 1973 to 1997-1998. In contrast, the number of lakes and their areal coverage in northern Alaska has decreased since 1955. These seemingly contradictory results suggest that potential change may not be spatially uniform, or that rates of lake expansion may vary regionally. Assessing the arctic system trajectory into the future therefore entails understanding fundamental ecosystem processes that vary over time and space.

The direct and indirect impact of changing lake dynamics on indigenous societies, and the impact of human activities on lakes and their biota, are central to this project. Understanding the interconnected physical, biological and social systems are required to identify process hubs, drivers and linkages; this necessitates an inter- and multidisciplinary approach.

Andrea Lloyd
Of the array of changes that have been identified in the Arctic System, changes in the surface of the Arctic--sea ice and the land surface--could have the most direct and immediate impact on human activities in the Arctic with the greatest effects extending outward to the more temperate latitudes. Indeed, a common component of SEARCH and of the challenges for the International Polar Year (IPY) is the characterization of changes in both the ocean surface and the land surface--collectively, the earth surface. We contend that changes in the surface of the Arctic are profound and will significantly impact human activities on local, regional, and global scales. Whereas past ARCSS initiatives have tended to focus on either land surface change (e.g., ATLAS), changes in the ocean system (e.g., SBI), or on human dimensions of global change (e.g., HARC), we propose the formation of a research community whose goal is to undertake the integrated study of earth surface changes in the Arctic, particularly as they interact with and affect humans in the Arctic system. The outcome of past domain-specific initiatives has been a substantial body of information from which we can conclude that both the land surface and the ocean surface are changing, that the rate of those changes may be unprecedented in recent times, and that the changes are beginning to affect human activities in the Arctic in tangible ways. We propose to pursue an understanding of the interactions between land and ocean surface change and their effects on human societies.

Patricia Matrai
OASIS will address how the air-surfaces exchange processes affect atmospheric chemical composition, and control the input of toxic chemicals to the Arctic Ocean system. As the nature and extent of Arctic snow and ice cover is changing, OASIS will assess the associated impact on, and by, climate change, and the human and ecosystem impacts of air-surface exchanges of chemical species. The OASIS program will produce essential data and knowledge, leave a legacy for continued polar research, and will inspire, educate and involve the general public, school-age children, and decision-makers worldwide.
Given that the atmosphere forms the upper boundary of the entire Arctic region, the exchange processes that occur there integrate over the entire system, including humans.
Since the atmosphere effectively has no transport barriers, it interacts with the global system importing and export gases, particulate matter and moisture. OASIS plans to study such interactions.

Gifford Miller
The largest variable on decadal to centennial timescales that impacts Arctic climate is the transport of heat and moisture from lower latitudes by the ocean-atmosphere system via the Nordic Seas. This system accounts for approximately one-third of the heat in the Arctic, and is known to vary in response to changes in the AO (frequencies 10-15 years). Holocene paleorecords document strong power also at 80 and 200 years, frequencies known to characterize variations in solar luminosity. High-resolution records (100 to 101 yr) for the past 500 to 7000 years are available from ice cores, tree rings, and select marine and lacustrine sedimentary archives. Considerable success in combining these records for the past 500 years has allowed a reconstructing of changing modes of AO variability, also with suggestions of low-frequency (80 to 200 yr) cyclicities. However, the records are not long enough to confirm these cycles.

We envision an international effort that focuses on refining of the Arctic/Icelandic/Northern Hemisphere tephra chronology and testing of its utility in marine, terrestrial and ice core archives from around the Atlantic Arctic. The team will focus on the impacts of volcanism on the Arctic system utilizing climate models, and to better utilize the time synchronization offered by diagnostic tephra from both Alaskan/Cascade and Icelandic sources to evaluate leads and lags in the climate system. In keeping with ARCSS Program Goals, this effort is strongly international with other Arctic-rim countries around the North Atlantic. Although our initial list of CoP participants is biased toward the North Atlantic regions, we envision a stronger contribution from the Pacific sector as the project develops.