Projected climate change impacts on hydrologic flow regimes in the Great Plains of Kansas

Alteration of flow regimes due to change in climate and its potential impact on habitat and species has become a major cause of concern for riverine ecosystems. Areas that are more vulnerable to such changes are semiarid river systems or regions experiencing intermittent flow and cyclic droughts. Although ecological changes are expected to occur with flow regime alterations, the biological changes cannot be predicted until the flow in such regions is analysed. This study addresses this concern by providing an analysis of flow for a semiarid river basin in the Central Great Plains from a 50 and 100-year projection climate data. The projected data for these two periods are then compared with 30-year historical data to determine changes in flow. Five major components of flow regime, magnitude, duration, and timing of annual extreme water conditions, frequency and duration of high and low pulses, and rate and frequency of water condition changes, were examined with respect to climate change for their impact on the ecology of the basin. This analysis strongly suggests that inter- and intra-annual changes in flow regimes will result in the intensified drying of the basin represented by the increased number of low flow periods followed by higher occurrences of high flow events of shorter duration with expected changes in climate.