2007 Annual Meeting and Arctic Forum | Abstracts

Influx of Freshwater Runoff to the Northern Atlantic Ocean from East Greenland

Sebastian H. Mernild^1
1IARC and WERC, University of Alaska Fairbanks, PO Box 750292, Fairbanks, AK, 99775, USA, Phone 907-474-2787, Fax 907-474-7041, fxsm@uaf.edu

The arctic climate is changing. Hydrological processes are changing and evolving in response to these changing conditions. In the Arctic the rough terrain and harsh climatic conditions yield a lack of cryospheric and hydrological knowledge. The limited data of such key components is a serious impediment to the hydrological research at East Greenland e.g., the amount and variation in cryosphere storage change and in influx of freshwater runoff to the North Atlantic Ocean. In arctic Greenland, the terrestrial cryosphere storage (snow, ice, and permafrost) does have an important influence in the high-latitude freshwater runoff contribution to the ocean.

Analyses of freshwater runoff from the only two East Greenland catchments have been done by glacier and snow observations, water flow observations, and experiments through the glaciers and the landscape, indicating glacier recession both places. Total freshwater runoff from the southern catchment (the Mittivakkat catchment) was ~3.7*10-2 km3 y-1 and from the northern catchment (the Zackenberg catchment) ~21.9*10-2 km3 y-1, high dominated by the percentage of glacier cover. The glacier recession dominates the mean annual catchment runoff by 30 to 90%. The total freshwater input up-scaled to the North Atlantic Ocean is ~450 km3 y-1 (1999-2004). The future (2071-2100) climate impact assessment based on the IPCC A2 and B2 scenarios modeled in HIRHAM indicates an increasing mean annual East Greenland air temperature by 2.7 degrees C. The 2071-2100 mean annual freshwater input to the North Atlantic Ocean is assessed to ~670 km3 y-1, an increase by approximately 50% from today's values, highly based on changes in air temperature rather than in precipitation and evapotranspiration.