Daily rainfall estimation using a GIS with weather radar imagery

Abstract

This research focuses on the integration, error correction and quantitative estimation of daily rainfall data based on C-Band weather radar imagery. This work includes a methodological proposal and a geomatic application in a Geographic Information System (Idrisi). The case study was based on the Cerro Catedral weather radar located in central Mexico, with a spatial and temporal resolution of 832.78 m and 15 min, respectively. Most determination coefficients (r2) for estimated daily rainfall based on radar information and information obtained by the Automatic Weather Stations ranged between 0.50 and 0.90, within a 150 km influence radius. Based on these results, the geomatic tool built serves as an alternative for estimating daily rainfall that improves and complements the rain gauge network. This facilitates the understanding of spatial-temporary variability in rainfall and justifies its use in hydrological and studies on integrated water resources management studies.