Maps of the hydrologic cycle components for Colombia

Clearly, water resources management under sustainable development policies requires adequate quantification of the different components of the hydrologic cycle. Besides, water plays a major role in majority of environmental issues and therefore developing good maps of rainfall, evapotranspiration and runoff is a fundamental contribution for sustainable development. We have developed a 5-arcmin digital atlas of monthly and long-term average rainfall, evapotranspiration and runoff for Colombia, including maps of input variables such as temperature, humidity, radiation, etc. The maps capture the spatial variability of the geophysical fields resulting from major geographic, topographic and climatic controls. The spatial scale of such maps has been defined as a function of the quantity and distribution of the observations and of the dependence structure of the field itself. Colombia has a great variety of hydro-climatic regions, due to its tropical location, mountain ranges and sea-land interactions. Construction of the rainfall map was based on the available rain gages observations, satellite estimates, re-analysis global maps and previous studies. For interpolation purposes we used Kriging with drift. Evaporation was estimated using diverse methods. Runoff was estimated using the water budget equation. The existing streamflow records at a wide range of basin sizes where then used for checking and evaluation of the methods, obtaining an average mean square error of 15%. Maps are digital, interactive and part of a more comprehensive and complex information systems (GIS). Estimation of diverse hydrological and climatological fields can be largely improved by including trans-boundary data, in particular for the tropical Americas. We present our approach to scientific issues that were faced during the construction process, related to scale and non-linearity of the processes. Undergoing work includes maps of extreme values and hydrological anomalies associated with El Niño-Southern Oscillation (ENSO) and sediment yield. Water resource management and planning and multiple applications in hydropower, agriculture, human health, sustainable development, ecology and other environmental and socio-economic tasks benefit from the maps.