UNOSAT code FL20230807LAO This map illustrates cumulative satellite-detected surface waters over Khammouan & Savannakhet Provinces, Lao PDR as oberved from a Sentinel-1 image acquired on 04 August 2023 at 18:04 local time.
Within the analysed area of about 25,000 km², a total of about 160 km² of lands appear to be flooded.
Based on Worldpop population data and the detected surface waters in the analysed area, ~18,000 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 the 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 backscaterring properties of the radar signal.
UNOSAT code TC20220928LAO, GDACS Id: 1000922 Typhoon Noru originated from a disturbance over the Philippine Sea. The storm made its first landfall over the Polillo Islands, Philippines on September 26 at 09:30 UTC and its second over Central Luzon five hours later as a high-end typhoon. The storm also made the third landfall in the early morning of 28 Sep 22 with winds of 117 km/h in the province of Quang Nam, home to the historic city of Hoi An and resort of Danang of Viet Nam. Typhoon Noru is expected to hit the central and southern provinces of Lao PDR on Wednesday, bringing heavy rain and thunderstorm to most of the country. According to GDACS, Typhoon Noru can have a high humanitarian impact based on the maximum sustained wind speed, exposed population, and vulnerability.
Based on data of the forecasted the cyclone path of wind speeds zones from Joint Research Centre (Issued on 28 September 2022 at 07:00 local time), and population data from WorldPop 2020, UNITAR-UNOSAT has prepared a population exposure analysis for Lao PDR. About 2% of population of Lao PDR living inside wind speed zone exceed 120 km/h, 16% living inside wind speed zone of 60-120 km/h and 20% living inside wind speed zone below 60 km/h
UNOSAT code TC20220928LAO, GDACS Id: 1000922 This map illustrates satellite-detected surface waters in Khongxedone District, Saravan Province & Sanasomboon, Champasak Province, Lao PDR as observed from a Sentinel-1 image acquired on 1 October 2022 at 05:45 local time. Within the extent of this map of 600 km2, about 14 km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the map extent, about 1,800 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 TC20220928LAO, GDACS Id: 1000922 This map illustrates satellite-detected surface waters in Sukhuma District, Champasak Province, Lao PDR as observed from a Sentinel-1 image acquired on 1 October 2022 at 05:45 local time. Within the extent of this map of 360 km2 , about 12 km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the map extent, about 2,500 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: FL20190905LAO This map illustrates satellite-detected surface water in Khammouan and Savannakhet Province of Lao PDR as observed from Sentinel-1 imagery acquired on 11 September 2019. Within the analysed extent of about 8,300 km2, a total about 332 km2 of land appear to be flooded as of 11 September 2019. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
Important Note: Flood analysis from Sentinel-1 imagery acquired on 11 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal
UNOSAT code: FL20190905LAO This map illustrates satellite-detected surface water in Champasak province of Lao PDR as observed from Sentinel-1 imagery acquired on 10 September 2019. Within the analysed extent of about 14,400 km2, a total about 53 km2 of land appear to be flooded as of 10 September 2019. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
Important Note: Flood analysis from Sentinel-1 imagery acquired on 10 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal
UNOSAT code: FL20190905LAO This map illustrates satellite-detected surface water in Salavan provinces of Lao PDR as observed from Sentinel-1 imagery acquired on 10 September 2019. Within the analysed extent of about 4,000 km2, a total about 4 km2 of land appear to be flooded as of 10 September 2019. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
Important Note: Flood analysis from Sentinel-1 imagery acquired on 10 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal
UNOSAT code: FL20190905LAO This map illustrates satellite-detected surface water in Attapeu provinces of Lao PDR as observed from Sentinel-1 imagery acquired on 10 September 2019. Within the analysed extent of about 6,000 km2, a total about 14 km2 of land appear to be flooded as of 10 September 2019. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
Important Note: Flood analysis from Sentinel-1 imagery acquired on 10 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal
UNOSAT code: FL20190905LAO This map illustrates satellite-detected surface water in southern provinces of Lao PDR as observed from Sentinel-1 imagery acquired on 6 September 2019. Within the analysed extent of about 60,000 km2, a total about 1,000 km2 of land appear to be flooded as of 6 September 2019. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.
Important Note: Flood analysis from Sentinel-1 imagery acquired on 6 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal
This map illustrates the satellite-detected surface waters extent in Samakkhixay district, Attapeu province, as observed from the KOMPSAT-5 imagery acquired on 30 July 2018. Satellite detected water extent analysis was performed by Centro Internazionale In Monitoraggio Ambientale Research (CIMA) & Luxembourg Institute of Science and Technology (LIST). Within the current map extent, a total of 1,617 ha were detected as inundated along the Xe Kong river. Disclaimer: Flood extent maps are derived from high quality satellite data using a scientifically validated retrieval algorithm. No liability concerning the contents or the use thereof is assumed by the producer. The information has limitations due to the quality and resolution of the original data sources, as well as the uncertainties associated with the retrieval algorithm. Please be aware that the thematic accuracy might be lower in urban and forested areas due to inherent limitations of the SAR analysis technique. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the satellite-detected surface waters extent in Sanamxay district, Attapeu province, as observed from the TerraSar-X and Tandem-X radar imagery acquired on 27 July 2018. Satellite detected water extent analysis was performed by Centro Internazionale In Monitoraggio Ambientale Research (CIMA) & Luxembourg Institute of Science and Technology (LIST). Within the analyzed area, a total of 7,405 ha were detected as inundated, four days after the collapse of the dam. Disclaimer: Flood extent maps are derived from high quality satellite data using a scientifically validated retrieval algorithm. No liability concerning the contents or the use thereof is assumed by the producer. The information has limitations due to the quality and resolution of the original data sources, as well as the uncertainties associated with the retrieval algorithm. Please be aware that the thematic accuracy might be lower in urban and forested areas due to inherent limitations of the SAR analysis technique. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates a time series analysis of the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province, based on satellite data collected on 13, 25 and 29 July 2018. Within the current map extent, on 13 July 2018, before the collapse of the dam, a total surface of 47,717 ha was detected as inundated and the reservoir controlled by the dam was full of water. As of 25 July 2018, two days after the dam collapsed, an additional surface of 7,531 ha of inundated areas were detected, representing an increase of the surface waters of 16%. On 29 July 2018, floodwaters are receding, especially along the riverbanks of Xe Kong River. A total surface of 30,435 ha was detected as inundated at that date, representing a decrease of the surface waters of 45%. The reservoir that was controlled by the dam has continuously decreased in its size since the dam collapsed. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. Additional optical VHR data are needed to validate analysis over areas covered by mud, hardly detected by radar data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This analysis illustrates a time series analysis of the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province,
based on satellite data recorded on 13, 25 and 29 July 2018.
This map illustrates the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province, as observed from the Radarsat-2 radar image acquired on 24 July 2018 and compared with a Radsarsat-2 image acquired on 10 July 2018. As of 10 July 2018, flooded areas and saturated soils were already visible, due to the heavy rains that happened previously to the collapse of the dam. As well, the reservoir controlled by the dam was full of water. As of 24 July 2018, an additional surface of 5,826 ha of inundated areas were detected, representing an increase of the surface waters of 66%, due to the collapse of the dam. At this date, the reservoir that was controlled by the dam has decreased in its size. Several villages and surrounding agricultural fields seems to be inundated. The villages of Ban Hinlat, Ban Thaseangchan, Ban Mai and Ban Samong-tai seems to be the most affected ones. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along the main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the satellite-detected surface waters extent in Sanamxay district, Attapeu province, as observed from the Radarsat-2 radar image acquired on 24 July 2018. The previous day, the Xe-Namnoy dam collapsed, inducing flash floods along the Vang Ngao river and affecting several villages located 50 km downstream. Within the analysed area 14,692 ha of surface waters were detected after the heavy rains that happened on 22 July and as well the collapse of the dam. Several villages and surrounding agricultural fields seems to be inundated. The villages of Ban Hinlat, Ban Thaseangchan, Ban Mai and Ban Samong-tai seems to be the most affected ones. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along the main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the satellite-detected surface waters extent in Sanamxay district, Attapeu province, as observed from the TerraSar-X and Tandem-X radar imagery acquired on 27 July 2018. Satellite detected water extent analysis was performed by Centro Internazionale In Monitoraggio Ambientale Research (CIMA) & Luxembourg Institute of Science and Technology (LIST). Within the analyzed area, a total of 7,405 ha were detected as inundated, four days after the collapse of the dam. Disclaimer: Flood extent maps are derived from high quality satellite data using a scientifically validated retrieval algorithm. No liability concerning the contents or the use thereof is assumed by the producer. The information has limitations due to the quality and resolution of the original data sources, as well as the uncertainties associated with the retrieval algorithm. Please be aware that the thematic accuracy might be lower in urban and forested areas due to inherent limitations of the SAR analysis technique. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates a time series analysis of the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province, based on satellite data collected on 13, 25 and 29 July 2018. Within the current map extent, on 13 July 2018, before the collapse of the dam, a total surface of 47,717 ha was detected as inundated and the reservoir controlled by the dam was full of water. As of 25 July 2018, two days after the dam collapsed, an additional surface of 7,531 ha of inundated areas were detected, representing an increase of the surface waters of 16%. On 29 July 2018, floodwaters are receding, especially along the riverbanks of Xe Kong River. A total surface of 30,435 ha was detected as inundated at that date, representing a decrease of the surface waters of 45%. The reservoir that was controlled by the dam has continuously decreased in its size since the dam collapsed. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. Additional optical VHR data are needed to validate analysis over areas covered by mud, hardly detected by radar data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This analysis illustrates a time series analysis of the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province,
based on satellite data recorded on 13, 25 and 29 July 2018.
This map illustrates the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province, as observed from the Radarsat-2 radar image acquired on 24 July 2018 and compared with a Radsarsat-2 image acquired on 10 July 2018. As of 10 July 2018, flooded areas and saturated soils were already visible, due to the heavy rains that happened previously to the collapse of the dam. As well, the reservoir controlled by the dam was full of water. As of 24 July 2018, an additional surface of 5,826 ha of inundated areas were detected, representing an increase of the surface waters of 66%, due to the collapse of the dam. At this date, the reservoir that was controlled by the dam has decreased in its size. Several villages and surrounding agricultural fields seems to be inundated. The villages of Ban Hinlat, Ban Thaseangchan, Ban Mai and Ban Samong-tai seems to be the most affected ones. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along the main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the satellite-detected surface waters extent in Sanamxay district, Attapeu province, as observed from the Radarsat-2 radar image acquired on 24 July 2018. The previous day, the Xe-Namnoy dam collapsed, inducing flash floods along the Vang Ngao river and affecting several villages located 50 km downstream. Within the analysed area 14,692 ha of surface waters were detected after the heavy rains that happened on 22 July and as well the collapse of the dam. Several villages and surrounding agricultural fields seems to be inundated. The villages of Ban Hinlat, Ban Thaseangchan, Ban Mai and Ban Samong-tai seems to be the most affected ones. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along the main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the evolution of satellite-detected surface waters in Sanamxay district, Attapeu province, as observed from the Radarsat-2 radar image acquired on 24 July 2018 and compared with a Radsarsat-2 image acquired on 10 July 2018. As of 10 July 2018, flooded areas and saturated soils were already visible, due to the heavy rains that happened previously to the collapse of the dam. As well, the reservoir controlled by the dam was full of water. As of 24 July 2018, an additional surface of 5,826 ha of inundated areas were detected, representing an increase of the surface waters of 66%, due to the collapse of the dam. At this date, the reservoir that was controlled by the dam has decreased in its size. Several villages and surrounding agricultural fields seems to be inundated. The villages of Ban Hinlat, Ban Thaseangchan, Ban Mai and Ban Samong-tai seems to be the most affected ones. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along the main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the satellite-detected surface waters extent in Sanamxay district, Attapeu province, as observed from the Radarsat-2 radar image acquired on 24 July 2018. The previous day, the Xe-Namnoy dam collapsed, inducing flash floods along the Vang Ngao river and affecting several villages located 50 km downstream. Within the analysed area 14,692 ha of surface waters were detected after the heavy rains that happened on 22 July and as well the collapse of the dam. Several villages and surrounding agricultural fields seems to be inundated. The villages of Ban Hinlat, Ban Thaseangchan, Ban Mai and Ban Samong-tai seems to be the most affected ones. It is likely that flood waters have been systematically underestimated along highly vegetated areas, along the main riverbanks and within built-up urban areas because of the special characteristics of the used satellite data. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR - UNOSAT.
This map illustrates the satellite-detected water extent in the District of Khongxedone, Salavan Province, in the southwestern part of Lao People’s Democratic Republic after the tropical storm SONCA-17. The UNITAR-UNOSAT analysis used a Sentinel-1 satellite image acquired on the 30 July 2017 and detected several areas with potentially standing waters. In the district of Khongxedone ~2,921 ha are likely flooded mostly affecting the central part of the district along the “Xe Don” river. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.
This map illustrates the satellite-detected water extent in the district of Khamkeuth in Borikhamxay province, in the central-northern part of Lao People’s Democratic Republic after the tropical storm SONCA-17. The UNITAR-UNOSAT analysis used a Sentinel-1 satellite image acquired on the 11 August 2017 and detected several areas with potentially standing waters. In the district of Khamkeuth ~2,441 ha are likely flooded. Kindly note, the district of Khamkeuth has been partially analyzed due to the image does not cover the full district. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.
This UNOSAT LIVE map integrates geo-spatial data in support of response efforts following Tropical Cyclone SONCA-17, after it made landfall in Laos on 26 July 2017.
More specifically, it was created with the aim of supporting a food security field assessment carried out by World Food Programme on the ground.
Up-to-date, comprehensive satellite image derived flood analyses are displayed, together with photos automatically uploaded from the UN-ASIGN smartphone app. Additional supporting GIS data are also included on the map.
