Satellite detected water extents from 1 Aug. 2024 to 22 October 2024 over Chiang Rai Province

**UNOSAT code: FL20240912THA** This map illustrates cumulative satellite-detected water extent from multiple satellites in Chiang Mai and Lamphun Provinces, Thailand, from 5 to 10 October 2024. Within the cloud-free analysed areas of about 4,000 km², about 245 km² of land appears to have been affected by flood waters, with around 70 km² of cropland inundated. Based on Worldpop spatial demographic data, about 228,000 people are exposed or living close to flooded areas. 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: FL20240912THA** This map illustrates cumulative detected water using multiple satellites and drone in Phayao Province, Thailand from 1 August to 12 October 2024. Within the analysed area of about 6,200 km², a total of about 360 km² of land appears to be affected by flood waters, with around 330 km² of cropland inundated. Based on Worldpop spatial demographic data, about 13,500 people are exposed or living close to flooded areas from 1 August to 12 October 2024. 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: FL20240912THA** This map illustrates satellite-detected water in Doi Tao District, Chiang Mai Province, Thailand, acquired on 6 October 2024 at 13:16 LT. Within the analysed area of approximately 800 km², about 54 km² of land appears to be affected by floodwaters, with around 30 km² of cropland inundated. Based on WorldPop spatial demographic data, approximately 140 people are exposed to or living near the flooded areas. 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 TC20220928THA, GDACS Id: 1000922** This map illustrates satellite-detected surface waters in Chaiyaphum and Nakhon Ratchasima Provinces, Thailand as observed from a RCM-2 image acquired on 4 October 2022 at 06:08 local time. Within the extent of this map of 1,100 km², about 240 km² of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the map extent, about 24,000 people are potentially exposed or living close to flooded areas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code: FL20210928THA** This map illustrates satellite-detected surface waters in Khon Kaen, Chaiyaphum, Nakhon Ratchasima, and Nong Bua Lam Phu provinces, Thailand as observed from a Sentinel-1 image acquired on 5 Oct 2021 at 18:20 local time and using an automated analysis with Machine learning method. Within the analyzed area of about 40,500 km2 , about 770 km2 of lands appear to be flooded. The water extent appears to have decreased of about 70 km2 since 29 September 2021. Based on Worldpop population data and the detected surface waters in the analyzed area, the potentially exposed population is mainly located in the district of Phimai with ~ 10,400 people, Non Sung with ~ 9,000 people, Mueang Chaiyaphum with ~ 6,700 people, Mueang Khon Kaen with ~ 4,500 people, and Chonnabot Thai with ~ 4,300 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). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code: FL20210928THA** This map illustrates satellite-detected surface waters in Central and Western parts of Thailand as observed from a Sentinel-1 image acquired on 21 October 2021 at 06:09 local time. Within the analyzed area of about 90,000 km2 , about 3,200 km2 of lands appear to be flooded. The water extent appears to have receded of about 70 km2 since 10 October 202. Based on Worldpop population data and the detected surface waters in the analyzed area, the potentially exposed population is 370,000 people mainly located in province of Phra Nakhon Si Ayutthaya with ~ 99,000 people, Suphan Buri with ~ 88,000 people, and Nakhon Sawan with ~ 47,000 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). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.