Increased flooded area and exposure in the White Volta river basin in Western Africa, identified from multi-source remote sensing data

Chengxiu Li, Jadunandan Dash, Moses Asamoah, Justin Sheffield, Mawuli Dzodzomenyo, Solomon Hailu Gebrechorkos, Daniela Anghileri, Jim Wright

Research output: Contribution to journalArticlepeer-review

24 Citations (Scopus)

Abstract

Accurate information on flood extent and exposure is critical for disaster management in data-scarce, vulnerable regions, such as Sub-Saharan Africa (SSA). However, uncertainties in flood extent affect flood exposure estimates. This study developed a framework to examine the spatiotemporal pattern of floods and to assess flood exposure through utilization of satellite images, ground-based participatory mapping of flood extent, and socio-economic data. Drawing on a case study in the White Volta basin in Western Africa, our results showed that synergetic use of multi-temporal radar and optical satellite data improved flood mapping accuracy (77% overall agreement compared with participatory mapping outputs), in comparison with existing global flood datasets (43% overall agreement for the moderate-resolution imaging spectroradiometer (MODIS) Near Real-Time (NRT) Global Flood Product). Increases in flood extent were observed according to our classified product, as well as two existing global flood products. Similarly, increased flood exposure was also observed, however its estimation remains highly uncertain and sensitive to the input dataset used. Population exposure varied greatly depending on the population dataset used, while the greatest farmland and infrastructure exposure was estimated using a composite flood map derived from three products, with lower exposure estimated from each flood product individually. The study shows that there is considerable scope to develop an accurate flood mapping system in SSA and thereby improve flood exposure assessment and develop mitigation and intervention plans.

Original languageEnglish
Article number3701
JournalScientific Reports
Volume12
Issue number1
DOIs
Publication statusPublished - Dec 2022

Fingerprint

Dive into the research topics of 'Increased flooded area and exposure in the White Volta river basin in Western Africa, identified from multi-source remote sensing data'. Together they form a unique fingerprint.

Cite this