Eurasian Arctic River Discharge: Relationship With the North Atlantic Oscillation and Long-term Trends
Abstract
The freshwater budget of the Arctic Ocean is dominated by river discharge. Ten percent of the world's runoff enters the Arctic Ocean, where it influences sea ice formation and ocean circulation. The fluctuation in the river discharge is affected by precipitation and snow melt, which in turn are affected by the atmospheric circulation. The effect of the North Atlantic Oscillation (NAO) on river discharge is examined for six major Eurasian Arctic rivers. The observed effects of the NAO on the discharge are compared with those simulated by a global climate model (GCM). Both the observations and GCM show a significant difference in river discharges during high and low NAO phases, although the observed differences are larger than those in the GCM. The eastern and western Eurasian rivers respond oppositely to the NAO. The GCM realistically simulates the annual cycles of three of these six rivers quite well, but generates too much discharge for the others. A model simulation with increasing greenhouse gases shows an increase in the peak summer flow in all rivers except the Ob. The model's long-term trends in river discharge are compared with observations for the last 50 years and are then projected 100 years into the future. The impact of river discharge on ice extent in the Barents Sea is also examined.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2004
- Bibcode:
- 2004AGUSM.H43A..02C
- Keywords:
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- 1655 Water cycles (1836);
- 1860 Runoff and streamflow;
- 1863 Snow and ice (1827);
- 4207 Arctic and Antarctic oceanography;
- 9315 Arctic region