Satellite detected water extents from 9 to 13 November 2024 over Nigeria

**UNOSAT code: FL20240902NGA, GDACS ID: 1102720** This map illustrates cumulative satellite-detected water using VIIRS in Nigeria between 5 to 9 September 2024. Within the cloud free analyzed areas of about 815,000 km², a total of about 14,000 km² of lands appear to be affected with flood waters. Based on Worldpop population data and the maximum flood water extent, about 2,650,000 people are potentially exposed or living close to flooded areas. The pixelwise water fraction from VIIRS, using a 5-day composite at 375 m spatial resolution, indicates potential floodwater coverage ranging from 0% to 100%. This large-scale analysis is intended for guidance purposes and has not yet been validated with ground truth data or higher-resolution analysis. The population exposure analysis is based on floodwaters observed only in cloud-free areas, so the total number of people exposed may be underestimated. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code FL20221019NGA** This map illustrates cumulative satellite-detected water using VIIRS in Nigeria between 1 to 25 October 2022 compared with the period from 1 to 30 September 2022. Within the cloud free analysed areas of about 912,000 km², a total of about 48,300 km² of land appears to be affected. In the analysed areas, 1,370 health facilities and 2,730 schools are identified to be within or close to a flooded zone. In comparison with the period between 1 to 30 September 2022, water extent appears to have increased of about 2,300 km². Based on Worldpop population data and the maximal flood water extent ~12,200,000 people are potentially exposed or living close to flooded areas amongst the 220 million people living in the analysed zone. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code FL20221019NGA** This map illustrates cumulative satellite-detected water using VIIRS in Nigeria between 19 to 23 October 2022 compared with the period from 13 to 17 October 2022. Within the cloud free analysed areas of about 873,000 km², a total of about 25,000 km² of land appears to be affected. In the analysed areas, 664 health facilities and 1,160 schools are identified to be within or close to a flooded zone. In comparison with the period between 13 to 17 October 2022, water extent appears to have decreased of about 5,000 km². Based on Worldpop population data and the maximal flood water extent ~5,200,000 people are potentially exposed or living close to flooded areas amongst the 197 million people living in the analysed zone. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code FL20221019NGA** This map illustrates cumulative satellite-detected water using VIIRS in Nigeria between 13 to 17 October 2022 compared with the period from 08 to 12 October 2022. Within the cloud free analysed areas of about 890,000 km², a total of about 30,000 km² of land appears to be affected. In the analysed areas, 738 health facilities and 1,424 schools are identified to be within or close to a flooded zone. In comparison with the period between 08 to 12 October 2022, water extent appears to have decreased of about 1,000 km². Based on Worldpop population data and the maximal flood water extent ~6,660,000 people are potentially exposed or living close to flooded areas amongst the 204 million people living in the analysed zone. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code: FL20210908NER** This map illustrates the extent of surface waters (cumulative) in Dosso, Niamey, Tahoua and Tillaberi regions of Niger as detected by VIIRS-NOAA satellite between the 2nd of August & the 5th of September 2021. Within the analyzed cloud free zones of about 260,000 km2, a total of about 900 km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters, about 120,000 people are potentially exposed or living close to flooded areas. The potentially exposed population is mainly located in the region of Dosso with ~40,000 people, Tillabéri with ~40,000 people and Tahoua with ~22,200 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT).

**UNOSAT code: FL20210908NER** This map illustrates the extent of surface waters (cumulative) in Dosso, Niamey, Tahoua and Tillaberi regions of Niger as detected by VIIRS-NOAA satellite between the 3rd & the 7th of September 2021. Within the analyzed cloud free zones of about 230,000 km2, a total of about 310 km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters, about 45,000 people are potentially exposed or living close to flooded areas. The potentially exposed population is mainly located in the region of Dosso with ~26,700 people, Tillabéri with ~10,900 people and Tahoua with ~6,600 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT).