3rd International Interdisciplinary conference on Predictions for Hydrology, Ecology and Water Resources Management: Water Resources and Changing Global Environment. 24-27 September 2012, Vienna, Austria

Assessment of possible change of design flood characteristics in mountainous permafrost basin caused by global warming

Lebedeva L., Semenova O. (2012) 

While climate warming in the Arctic is a generally recognized fact, its impact on hydrological processes is still unresolved issue. The Russian Arctic has great potential for the development of hydropower industry which would require reliable assessment of design flood characteristics in changing conditions as a base for effective management and environment safety in future.

Traditionally in Russia the frequency analysis of observed runoff characteristics is used within the tasks of engineering and design. Those statistical methods developed on the basis of assumption of hydrological processes stationarity do not include the comprehension of physical processes in catchments and may lead to erroneous assessment of runoff characteristics under present and future climate change conditions. The alternative method is the application of a process-oriented hydrological model coupled with the data of global climate models as sources of forcing meteorological data.

The Kankunskayahydropowerplantisbeing constructed on the Timpton river which is located at the upstreams of the Lena River in southern Yakutia. The basin is characterized by mountainous relief and severe climate conditions. It is covered by discontinuous permafrost which greatly affects its hydrological regime.

The aim of the study is to assess possible changes in runoff characteristics of the Timpton River at the Kankunskaya dam location by 2035, 2050 and 2100 using the CMIP5 projections and the hydrological model Hydrograph. The Hydrograph is a distributed deterministic model of runoff generation processes developed by Hydrograph Model Research Group (www.hydrograph-model.ru). The model parameters are observable properties of soil and vegetation and require minimum of manual calibration. Therefore it has a high potential to be applied in the tasks of climate change impacts assessment.

The ensembles of meteorological data for the Hydrograph model were derived from the CMIP5 results. The design flood characteristics of the Timpton river were assessed based on simulated daily flows corresponding to different scenarios of climate in 2010-2100.

The runoff characteristics calculated by i) the traditional method ii) the Probable Maximum Flooding (PMF) approach and iii) using deterministic hydrological modelling combined with the outputs of global climate models would be compared and analyzed. Analysis of the results and the recommendations of designed dam characteristics will be presented. 

permanent link to this abstract: http://hydrograph-model.ru/abstract.php?mode=external&id=19