ALBERT

Description: Understanding of future climate change impacts and successful planning of adaptation measures are of vital importance for Central Asia given the region's economic vulnerability, dependence on scarce water resources, and observed above global average warming rates. This paper analyses how impacts of climate change on the hydrological regimes and temperature patterns could affect the irrigated agricultural production in two case study areas, the Aspara and Isfara river basins. The methodology applied is based on analysis of temperature indicators and current cropping calendars in target locations combined with hydrological simulations by the process-based Soil and Water Integrated Model (SWIM) of the two river basins. The selected climate change projections comprise the moderate and high emissions scenarios - RCP4.5 and RCP8.5. The results reveal that climate change will create unfavourable conditions for irrigated spring crops, due to decrease of discharge during the vegetation period. On the other hand, the projected shift of peak discharge to an earlier date offers benefits for irrigated winter cereals, providing more water for irrigation in spring. Results suggest that, there is an opportunity to adapt the irrigated agricultural production in the selected regions by fitting the cropping calendars to changing vegetation periods and to the timing of peak discharges.

Description: Study region Eight river catchments within Central Asia. Study focus The limited amount of water resources is already an issue in the Central Asian region, and climate change may be crucial for water availability and development of countries in the region. This study investigates potential climate change impacts on water resources in Central Asia to the end of the century by focusing on eight river catchments with diverse natural conditions located in different countries. The eco-hydrological model SWIM was setup, calibrated and validated for all selected catchments under study. Scenarios from five bias-corrected GCMs under Representative Concentration Pathways 4.5 and 8.5 were used to drive the hydrological model. New hydrological insights for the region The results show an increase of mean annual temperature in all catchments for both RCPs to the end of the century. The projected changes in annual precipitation indicate a clear trend to increase in the Zhabay and to decrease in the Murghab catchments, and for other catchments, they were smaller. The projected trends for river discharge are similar to those of precipitation, with an increase in the north and decrease in the south of the study region. Seasonal changes are characterized by a shift in the peak of river discharge up to one month, shortage of snow accumulation period, and reduction of discharge in summer months.