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We use a new set of data available to compute 21st century climate impacts on the hydrology of 221 catchments in high-mountain Central Asia. For each of these subcatchments, a parsimonious steady state stochastic soil moisture water balance model was set up and the partitioning of available water from precipitation into runoff and evaporation computed for different climate futures using the Budyko framework. Climate change sensitivity coefficients are analytically derived for the first time using the total differential method. Relative changes in discharge for three future periods 2011–2040, 2041–2070, and 2071–2100 were computed in relation to the baseline period from 1979–2011. For the baseline observation period, climate data from a global high-resolution climatology data set (CHELSA V21) were used to extract mean daily subcatchment-specific temperature and precipitation values. Data from the coupled model intercomparison project phase 6 (CMIP6) were used to compute catchment mean future climate data using 4 GCM models with 4 scenario runs each. CMIP6 data were bias corrected with CHELSA V21 observation data. For the spatial distribution of soil parameters, different global products were utilized. The robustness of the soil water balance model results was assessed using a comprehensive sensitivity analysis in relation to variations of these soil parameters over typically observed ranges for each subcatchment. The analysis of climate change suggests increasing precipitation over the three periods (+4.44 %, +5.89 %, and +8.51 % relative increases in median total precipitation averaged over subcatchment and scenarios). Median values of temperatures changes between periods relative to the baseline are +1.33 °C, +2.44 °C, and +3.55 °C. Results of the hydrological soil water balance model runs suggest a median increase of discharge of +4.71 %, +7.44 % and +10.87 % for the corresponding periods. This is a strong indication of a wetter and hotter future in Central Asia, relative to today's hydroclimate. Modelling results suggest that decreasing contributions from glacier melt over the course of the 21st century will be offset by increases in discharge consistently throughout the region, despite increasing potential evapotranspiration. Increases in relative discharge will be most pronounced in the Afghan Murghab-Harirud basin and in the Amu Darya. Changes in precipitation characteristics in terms of frequency and event depth also indicate possible impacts on hydrological extremes which remains a heavily under researched topic in Central Asia. [ABSTRACT FROM AUTHOR]

Numerical modelling is often used for climate impact studies in water resources management. It is, however, not yet highly accessible to many students of hydrology in Central Asia. One big hurdle for new learners is the scripting requirement for the preparation of relevant data prior to the actual modelling. We present a robust, open-source workflow and comprehensive teaching material that aims at bridging the gap between theoretical hydrological modelling know how and applied modelling for climate impact studies in Central Asia. The teaching material has been refined during two consecutive years and is being taken up by several professors teaching hydrological modelling in Central Asia. [ABSTRACT FROM AUTHOR]

Management of common‐pool resources in the absence of individual pricing can lead to suboptimal allocations. High‐frequency data from three irrigation schemes in Mozambique reveal patterns consistent with water inefficiency. Farmers use the amount of water required at the most sensitive stage of production as a benchmark for all allocations in the crop cycle. We demonstrate that these rule‐of‐thumb approaches create scarcity at the plot level despite schemes having sufficient water to meet farmers' individual demands. We therefore explore the possibility of a feedback tool that visually communicates to farmers the potential to conserve by varying water applications at each stage of the crop cycle. To test the importance of tailoring the information to farmers' own settings, we randomize a set of farmers to also receive visualizations comparing water requirements with each farmer's water use in the same season of the previous year. The experiment fails to detect an additional effect of individualized comparative feedback relative to a general information treatment. Water measurement shows that the gains from correcting observed misallocations of water in terms of water savings and avoided scarcity is potentially large as a share of water used in the agricultural sector. These findings support additional testing of feedback tools to encourage water conservation but not the expensive investments that would be required to generate feedback based on individual metering for all targeted farmers. [ABSTRACT FROM AUTHOR]