Approach

We are using a suite of collaborations, research projects, previous literature, citizen science activities and funding from the National Science Foundation and the UAA Environment and Natural Resources Institute (ENRI) to collect, analyze and develop AKWIN. Our program has flagship sites in Denali National Park, Caribou-Poker Creeks Research Watershed and Juneau as part of the National Atmospheric Deposition Program, with a new site coming on line in King Salmon in 2010. We also have long-term data from the North Slope (Toolik Lake).

AKWIN-affiliated researchers have undertaken lake, stream and river sampling across the state as part of USGS, EPA, and NSF research activities. Our sampling includes watershed-based high frequency data, as in the Girdwood Valley where glacier and non-glacier fed streams area are present, precipitation time series in Anchorage (Tideview station), broad-based spatial sampling of lakes on the N Slope and in Southcentral AK along with river water sampling along a transects from the Brooks Range to the Arctic Ocean. We utilize three new Picarro Wavelength Scanned Cavity Ring-Down Spectroscopy instruments that are providing the isotopic water analysis capacity for our network and are housed in the ENRI Stable Isotope Lab.

Long-Term Precipitation Studies in Alaska

The three long-term USNIP sites in AK (Denali, Caribou Poker, Juneau) provide the flagship sites for AKWIN. These study sites have been collecting samples since the the mid-1980s and provide the basis for our time-series, storm track and climate changes analyses. We know that the interior of AK has warmed in recent years and will be examining whether this is depicted in the isotopic enrichment in the monthly and annual averages and whether these patterns are consistent across all of Alaska.

Glacier to Bay in the Girdwood Valley: High Frequency Time Series

As part of the UAA Renewable Energy Research and Discovery Center, we are quantifying the discharge and the stable isotope geochemistry of Alyeska Creek and surrounding streams and rivers. We are interested in the daily variation in responses to episodic rainfall events and we seek to estimate the proportion of stream water derived from the mountain glaciers, groundwater and rainfall. These data will aid in the research and development of microhydrological power generation sites in the Girdwood valley and across Alaska.

Storm Track Contribution to Local Precipitation Isotopic Variability

Station-specific precipitation sampling by citizen scientists are providing new insights regarding the processes and dynamics of the Alaskan hydrologic cycle. Event-based sampling at the Tideview station in Anchorage (JM Welker operator) are depicted above and show strong interannual variability that may be driven by temperature and storm track dynamics. Differing storm tracks can be a major source of isotopic variability in local precipitation. AKWIN will use high frequency sampling paired with NOAA Hysplit storm track data to determine the extent of this effect as a function of local geography.