Satellite Detected Water Extent in Maheshkhali, Chakaria and Cox'S Bazar Sadar Upazilas

This map illustrates satellite-detected surface water extent in the District of Cox's Bazar, Chittagong Division, located in the southeastern part of Bangladesh after the tropical cyclone Mora-17 using a Sentinel-1 satellite image acquired on the 30 May 2017. A total of 23,058 ha surface waters were observed. In many zones, the affected lands are mainly agricultural. The analysis of this image reveals also that about 234 km of roads mainly tertiary roads seem to be potentially affected. The population exposure analysis using WorldPop data shows that ~267,000 people are potentially affected by floods within map extent. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.

This map illustrates satellite-detected surface water extent in the central and southern parts of Bangladesh using a Sentinel-1 satellite image acquired on the 22 August 2017. In the analysed area; 608,747 ha of lands are likely affected. These lands are mainly cropland irrigated and rainfed areas and estimated to 475,000 ha. The population exposure analysis using WorldPop data shows that ~6,400,000 people are potentially affected by floods in the analysed zone: ~2,300,000 are located in Chittagong Division and ~2,170,000 in Dhaka Division. Please note that for visualization purposesanalyzed area is wider than the extent of this map. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.

This map illustrates satellite-detected surface water extent in the northern part of Bangladesh using a TerraSAR-X satellite image acquired on the 16 August 2017. In the analysed area; 221,915 ha of lands are likely affected. The population exposure analysis using WorldPop data shows that 2,143,586 people are potentially affected by floods in this analysed zone: ~1,800,000 are located in Rangpur Division and ~280,000 in Dhaka Division. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.

This map illustrates satellite-detected surface water extent in the central and northern parts of Bangladesh using a Sentinel-1 satellite image acquired on the 22 August 2017. The total analysed area is about 4,284,431 ha. In this analysed area; 1,099,369 ha (39%) of lands are likely affected. These lands are mainly cropland irrigated and rainfed areas and estimated to 1,039,350 ha. The population exposure analysis using WorldPop data shows that ~10,000,000 people are potentially affected by floods in the analysed zone: ~5,400,000 are located in Dhaka Division and ~2,750,000 in Rajshahi Division. Please note that for visualization purposes the analyzed area is wider than the extent of this map.This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.

**UNOSAT code: FL20210729BGD** This is a web map showing analysis and results related to floods in Cox's Bazar area, Chittagong division, Bangladesh

This map illustrates satellite-detected surface water extent in Teknaf Upazila, District of Cox's Bazar, Chittagong Division, located in the southeastern part of Bangladesh as detected using a Sentinel-1 satellite image acquired on the 13 June 2018 compared to a Sentinel-1 satelllite image acquired on 22 May 2018. The total analysed area is about 5,000 ha, and about 1,600 ha of surface waters could be observed on 13th of June 2018 whereas 1,050 ha were observed on 22 May 2018. The increase of observed surface waters in this area is about 50 %. Within the camps' extents, 52 ha of water were detected and the most affected seems to be camp 25. Please note that in many zones, the affected lands are mainly agricultural and open areas. It is likely that flood waters have been systematically underestimated along highly vegetated areas along main river banks and within built-up urban areas because of the special characteristics of the satellite data used. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR UNOSAT.