Satellite Detected Waters Extent and Evolution in Maroantsetra area, Analanjirofo region, Madagascar

This map illustrates satellite-detected flood waters over Maroantsetra area, Analanjirofo region in Madagastcar as observed from the TerraSAR-X radar image acquired on 08 March 2017 compared with to a Radarsat-2 image acquired on 04 May 2014. Several zones seem to be inundated and have experienced an increase of standing waters. These zones are mainly agricultural and/or swamps around the town of Maroantsetra. These waters seem to be the results of the recent heavy rain related also to the cyclone ENAWO-17 which made landfall the 07 March 2017. 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.

This map illustrates satellite-detected water extent as of 10 March 2017 over Antsahanoro commune, Antalaha district in Madagascar as detected by TerraSAR-X. As of 10 March 2017, ~ 335 Ha of land over Antsahanoro commune seem to be inundated and have experienced an increase of standing waters. These zones are mainly agricultural and/or swamps in the commune of Antsahanoro. These waters seem to be the results of the recent heavy rain related also to the cyclone ENAWO-17 which made landfall the 07 March 2017. 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.

**UNOSAT code: TC20250308MDG, GDACS ID: 1154** This map illustrates the potentially affected cropland in Maroantsetra District, Analanjirofo Region, Madagascar, based on RCM-2 satellite images acquired on 9 March 2025. In the analyzed area of approximately 1,200 km², about 140 km² of cropland is identified, of which about 35 km² appears to be affected by floodwaters. This is a preliminary analysis and has not yet been validated on the ground. Ground feedback is requested and can be sent to the United Nations Satellite Centre (UNOSAT). Important Note: Flood analysis based on radar images may underestimate the presence of standing water in built-up or densely vegetated areas due to the backscattering properties of the radar signal.

This map illustrates satellite-detected water extent as of 09 January 2018 over Soaneriana Ivongo district, Analanjirofo region, in Madagascar as detected by Radarsat-2. Limited standing waters can be observed in the area. These zones are mainly agricultural and/or swamps. These waters are the results of recent heavy rains following the cyclone AVA-18 which made landfall the 05 January 2018. It is likely that flood waters have been systematically underestimated along highly vegetated areas along main river banks and within built-up urban areas, due to 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.

This map illustrates satellite-detected water extent as of 07 January 2018 over Toamasina districts, Atsinanana Region, in Madagascar as detected by Sentinel-1. Some standing water areas could be observed north and south of Toamasina, mainly in the agricultural and/or open areas along the river. It is likely that floodwaters 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.

This map illustrates satellite-detected water extent as of 07 January 2018 over Mananjary district, Vatovavy-Fitovinany region, in Madagascar as detected by Sentinel-1. ~ 1000 ha of land over the communes of Tsiatosika and ~1300 ha in Ankatafana seem to be inundated. These zones are mainly agricultural and/or swamps. These waters are the results of recent heavy rains following the cyclone AVA-18 which made landfall the 05 January 2018. It is likely that flood waters have been systematically underestimated along highly vegetated areas along main river banks and within built-up urban areas, due to 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.