Drainage Network Extraction of Brazilian Semiarid Region with Potential Flood Indication Areas

摘要

This region has the particularity of, at the same time, coexisting with sporadic floods and scarcity of water. This situation requires complex studies involving water resources based on runoff of rain waters and on the courses of the rivers. For the extraction of drainage was carried out by using of the system for hydrological modeling treatment TerraHidro, developed by INPE's Image Processing Division. This system uses the PFS method for extraction of drainage, which has provided good results, enabling the reduction of the time spent on manual editing of drainage errors. TerraHidro has a tool called Height Above the Nearest Drainage (HAND) which gives information on potential flood areas. Elevation data were used in the Aster GDEM with spatial resolution of 30 meters for drainage extraction. A qualitative comparison was performed between drainage extracted by TerraHidro and drainage manually extracted by a specialist.