Developing an Understanding and Predictive Capability of the Interconnections Among Arctic Terrestrial, Atmospheric, and Marine Systems
Arctic ecosystems are both tightly linked to the earth arctic systems (land, ocean, and atmosphere) and are highly sensitive to the effects of global warming and climate change. Recent studies indicate that the most significant rise in temperature resulting from increased greenhouse gases is anticipated to occur within the Arctic. Because the land, sea, and atmospheric systems are inextricably linked, it is important to assess this interaction within the context of global change and the resultant impacts of such change. The potential for amplification of resultant impacts, based on multiple positive feedbacks between these systems, will be relevant at regional as well as global scales.
The three scientific goals of this project are to:
Estimate the historic and future impacts of variability within the ocean and atmospheric systems on terrestrial fluxes of gaseous (including CO2 and water vapor) and non-gaseous (particulate and dissolved organic matter, nutrients, and water) materials and energy between the land and the atmosphere and sea;
Evaluate the impacts of variation in radiation, climate, ocean circulation, ocean temperature, and sea ice position and extent on terrestrial processes, including those that have feedback on atmospheric and ocean processes; and
Provide high-resolution products (atmospheric, ice, ocean, and terrestrial) and related datasets, relevant to the patterns and controls of terrestrial and oceanic processes, for use in future analyses, including, but not limited to, other SNACS projects.
The methods for reaching these goals are (A) Use of the regional atmospheric model, Polar MM5, to produce high-resolution atmospheric data for the North Slope of Alaska; (B) Determination and utilization of carbon flux rates and meteorological states from SDSU’s Sky Arrow aircraft and eddy covariance tower network to obtain regional estimates of carbon balance, and to verify regional modeling; (C) Use of satellite monitoring to quantify spatial patterns and temporal variability of Arctic vegetation structure, productivity, and landscape freeze-thaw state using AVHRR and MODIS; (D) Utilize Biome-BGC and RHESSys ecosystem model simulations of terrestrial carbon and hydrological to conduct detailed site simulations of daily carbon, water, and nitrogen budgets at a range of spatial scales and extents within the study domain; (E) Utilize a high-resolution, regionally coupled ice-ocean model to assess sea ice extent and oceanic processes; and (F) Utilize a physically-based, spatially-distributed hydrologic model to assess hydrologic processes at the watershed scale, providing information on moisture dynamics within and among landscape units in order to assess integrated hydrologic responses on a watershed scale to be verified against measurements of soil moisture and to examine consequent effects such as groundwater flux, stream discharges, and biogeochemical processes.