Are there any simple tools to calculate the basic water balance for a region despite the lack of hydrology data?
We would like to do calculations although we have very little data for rainfall/river discharge measurements and meteorological data (evapotranspiration).
Today, more and more satellite data sets on rainfall, evapotranspiration and other hydrological variable are freely available from several Internet. These permits simple spatial water balancing exercises to be made. Sparse ground observations or data can be used to check or bias control the In many semiarid regions of the world, surface water provides a major source of water supply. River runoff occurring during the rainy season is stored in surface reservoirs to sustain human, agricultural and industrial water use during the dry season. The reservoirs are interconnected via the river network, mutually influencing their inflow and outflow volumes. Rain and snowfall are key components of land surface models, including the Land Data Assimilation Systems (LDAS), investigations into how water and energy cycle through natural systems, as well as monitoring water for human activities. I recently tested TRMM version 7 precipitation data and temperature from CFSR reanalysis dataset (to compute potential evapotranspiration using Hargreaves-Samani method) to compute discharges using a hydrological model in the Mekong river catchment in South-East Asia