Cyclone Nargis and Myanmar floods seen from space

These Envisat radar images highlight the extent of flooding in the Irrawaddy delta caused by the cyclone Nargis that hit Myanmar on May 3, 2008, devastating the country. The left... Click here for more information.

With inundated areas typically visible from space, Earth Observation (EO) is increasingly being used for flood response and mitigation. One of the biggest problems during flooding emergencies is obtaining an overall view of the phenomenon, with a clear idea of the extent of the flooded area.

The series of Envisat radar images highlights the extent of flooding in the Irrawaddy delta caused by the cyclone. Envisat’s Advanced Synthetic Aperture Radar (ASAR) acquired the image on the left on 5 February 2007, and the image on the right on Monday (5 May 2008).

The left image shows the situation approximately one year ago. The black and dark areas in the image on the right indicate areas potentially still flooded two days after the event. ASAR data are especially well suited for delivering information on floods, which are usually accompanied by rain and therefore cloudy conditions. Radar sensors can peer through clouds, rain or local darkness and are especially sensitive to moisture on the ground.

The recent image was delivered in Near Real Time and processed to correlate to the previous image. Both images have a 75 m pixel grid on the ground and show an area approximately 100 km wide.