ANALYSIS OF SATELLITE-BASED RAINFALL DATA DURING FLASH FLOODS ON SUMATRA ISLAND (CASE STUDY: FLASH FLOODS 2011-2021)

• Main Author: Zel Aliefya, Salsabila
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/74888
• Institution: Institut Teknologi Bandung

Flash floods that occur suddenly cause a lot of losses. Flash floods usually occur in catchment areas which tend to be small with an area of less than 1000 km2 caused by extreme rainfall. However, the observation and monitoring of flash floods requires many aspects, due to spatial limitations, there are no meteorological observation stations in the vicinity. Therefore, another alternative is needed to find the best satellite that can identify rainfall at the time of flash floods, as well as knowing important information/characteristics from satellite data related to flash floods. In this study, Global Precipitation Measurement (GPM) data, Global Satellite Mapping of Precipitation (GSMaP) data, and several observation station data will be used. The data is then processed using the Gumbel distribution method to find the value of the return period and its comparison ratio with 1 day, 2 days, 5 days, and 10 days of rainfall. GPM and GSMaP data will be tested for validity using observation station data through the results of a comparison of the rainfall ratio values. The result of calculating the ratio of the return period value to the rainfall value of each satellite is that GPM can show more events with heavy rain categories in 1 daily, 2 daily, 5 daily, and 10 daily rainfalls compared to GSMaP. In addition, there are more extreme events during flash floods identified by the GPM for a longer duration. It can be seen from the results of the 10 daily rainfall events, the satellite can show a higher number in the heavy rain category.