Abstract
The effects of changes in rainfall and temperature on runoff in the Wabash River basin were studied using a monthly water balance model. Two types of simulations were conducted. In one type, observed rainfall and temperature sequences with changed means were used to simulate runoff. In the other type, stochastic precipitation sequences were used with the calibrated model to compute runoff. Changes in runoff characteristics are examined. The model incorporates precipitation, snowmelt, evapotranspiration, soil moisture, groundwater storage, storm runoff, and base flow. Input data used in the study are reviewed. The model satisfactorily simulates the general trends observed in hydrographs. The model can predict runoff variations using eight possible climate change scenarios. Precipitation changes will cause significant runoff changes in all seasons, while temperature changes have a lesser effect.