Monitoring flooded areas with Sentinel-1 satellite data
From 13 – 15 July, exceptionally persistent and heavy rainfall, caused by a stationary low-pressure area over southern Germany, fell over the Ardennes, Eifel, and surroundings in Belgium, the Netherlands, and Germany. In many locations it rained almost constantly throughout these 3 days and rain totals locally became > 200 mm, an amount that normally falls in about 3 months.
The radar instrument on-board the Sentinel-1 satellite, capable of observing the Earth under cloudy circumstances, shows the effects of this exceptional rainfall episode. The slide animation below alternates between Sentinel-1 images of 9 and 15 July 2021 (see in the EO viewer). The flooded areas of the Meuse river and her tributaries are clearly visible as increased blue regions in the 15 July image.
The TerraFlood service, an initiative of the Flanders Environment Agency (VMM), Ghent University, and VITO, offers the possibility to generate comparable flood mapping images. This free application provides a clear flood mapping within 24 hours after occurrence and provides additional flood dynamics and frequency information. This information is very valuable to e.g. governments and companies involved in quantitative water management, the agricultural sector, and environmental agencies.