IUGG 2011, 28 June – 7 July 2011, Melbourne, Australia _ 1

Assessment of possible climate change impacts on runoff regime of mountainous watersheds of Eastern Siberia

Olga Semenova

One of the unresolved issues of climate change is how the changing heat-water regimes would impact the Arctic rivers streamflow at different scales. In this study we tried to assess possible changes of annual, seasonal and extreme runoff characteristics of several mountainous rivers in Eastern Siberia using various scenarios of climate change.

The deterministic-stochastic modelling system (DSMS) developed in State Hydrological Institute of Russia was applied in this study. It consists of two modules: deterministic process-based hydrological model Hydrograph and the stochastic weather generator.

The first stage of the study included verification of existing deterministic model at historical data set for several watersheds in the Lena River basin. The ability to transfer most of the parameters from small to middle and large basins without calibration and low requirements of input meteorological data confirmed that the existing deterministic model has an appropriate foundation for climate change impact assessment on hydrological characteristics, particularly in the permafrost areas. Next task was deriving ensembles of scenarios of future climate using the developed stochastic weather generator and IPCC climate change scenarios.

The results of the DSMS application to several watersheds of different sizes ranging from 40.2 km2 to 696000 km2 (the River of Aldan) within the Lena River basin will be demonstrated. They will include comparison of probabilistic distribution curves of simulated by different climate change scenarios runoff characteristics with historically observed values.

permanent link to this abstract: http://hydrograph-model.ru/abstract.php?mode=external&id=11