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Streamflow Regime and Changes in Large Northern Watersheds: Human Impacts vs. Natural Variations. Daqing Yang, Douglas Kane Water and Environment Research Center University of Alaska Fairbanks, AK99775 Baisheng Ye
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Streamflow Regime and Changes in Large Northern Watersheds: Human Impacts vs. Natural Variations Daqing Yang, Douglas Kane Water and Environment Research Center University of Alaska Fairbanks, AK99775 Baisheng Ye Cold & Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, P. R. China
Reservoir A J I A K H F N E G D B M C L
Monthly flow regime and change Lena river, 1935-94 Yenisei river, 1936-1995 Monthly discharge (m3/s) Ob river, 1930-94
Annual discharge and trend for Ob, Yenisei & Lena rivers, 1930-95
Annual precipitation and trend in large Siberian basins, 1935-98
LENA – KUSUR Area ----2,430,000km2 Runoff ---523.9km3 Data ---1939-1994 A H G D B E Aldan tributary Area ----28.6% Runoff ---- 30% Data ---1942-1990 F Vilui reservoir, operated in 1967, max. capacity 35.9km3, 7% Lena River total runoff C Vilui basin Area ---18.6% Runoff ---- 9% Data ---1936-1990 Upper Lena basin Area ----36.9% Runoff --- 42% Data ---1936-1990
Monthly discharge (m3/s) Reservoir Effect on Streamflow
Monthly mean discharge for pre-dam (1942-67) and post-dam (1968-90) periods at the 4 stations Monthly discharge (m3/s)
Dam Impact on Water Temp: Mean stream temperatures, predam (1950-67) vs. postdam (1968-92) periods, Suntar station. June discharge and June 20 stream temperature, Suntar station.
Monthly discharge trends for major sub-basins and at Lena basin outlet
Reconstruction of monthly discharge at basin outlet Regression functions between upstream and downstream Q: June: Qoutlet = 0.315+3.315Q1+0.813Q2 May: Qoutlet = 660.8e0.0002Q2
Reconstructed discharge (m3/s) Observed discharge (m3/s) Comparison between the observed and reconstructed monthly discharge at Lena basin outlet / Kusur station
Comparison between observed and reconstructed monthly discharge at the Lena basin outlet, 1942-90 Monthly discharge (m3/s)
Comparison of observed vs. reconstructed mean flows at Kusur station
Comparisons of annual discharge and its trend, observed vs. reconstructed, Lena basin outlet
Reservoir A J I A K H F N E G D B M C L