Image Library

Emergency observation of concentrated heavy rain in Hiroshima Prefecture by AVNIR-2 onboard "Daichi" (ALOS) (2)

The record-breaking concentrated heavy rain which fell 72-millimeter per hour, occurred at Shobara city in Hiroshima Prefecture on July 16, 2010 (JST), this caused great damage due to floods of river and mudslides.

The Japan Aerospace Exploration Agency (JAXA) has performed the emergency observation to monitor the state of the damage by the Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2)* onboard the Advanced Land Observing Satellite (ALOS, "Daichi") at 11:09 on July 21, 2010 further to July 19 and 20, 2010 (JST).

Fig. 1 shows an observed image of AVNIR-2 at 11:09 on July 21, 2010 (JST). It is the true colored composite using band 3, 2 and 1 of AVNIR-2. Although there are several clouds, fortunately there is no cloud at the areas of landslide disaster and the ground could be seen.
Fig.1
Fig.1: AVNIR-2 image with 15.0 degrees pointing angle acquired at 11:09 on July 21, 2010 (JST). Yellow squares show location of Figs. 2 to 4.
(Click to view enlarged image)
Fig. 2 shows enlarged images of Saijo cho, Shobara city where mudslide occurred, and fig.3 shows enlarged images of fig. 2. Since they are the false colored composite using band 4, 3 and 2 of AVNIR-2, they clearly indicate the areas where vegetation was lost due to mudslides. Though the area could not been seen at the image taken on July 20, 2010 due to clouds, the areas of mudslides could be seen at image taken on July 21, 2010.
Fig.2
Fig.2: Enlarged image of Saijo cho, Shobara city where mudslide occurred (36 square kilometers, left: July 21, 2010; middle: July 20, 2010; right: June 26, 2009).
(Click to view enlarged image)
Fig.3
Fig.3: Enlarged image of Saijo cho, Shobara city where mudslide occurred (4 square kilometers, left: July 21, 2010; middle: July 20, 2010; right: June 26, 2009).
(Click to view enlarged image)
Fig. 4 shows enlarged images of Sougaya River. The area of mudslides in the image taken on July 20, 2010 couldn't be seen clearly, but the state which landslides flow out in the image taken July 21, 2010 could be seen.
Fig.4
Fig.4: Enlarged image of Sougaya River (1 square kilometer, left: July 21, 2010; middle: July 20, 2010; right: June 26, 2009).
(Click to view enlarged image)

The acquired images were provided to the followings,

  • Cabinet Secretariat
  • Cabinet Office, Government of Japan
  • National Police Agency
  • Fire and Disaster Management Agency
  • Ministry of Defense
  • Ministry of Land, Infrastructure, Transport and Tourism
  • Japan Meteorological Agency
  • Japan Coast Guard
  • Public Works Research Institute

JAXA plans continuous observation of this area.

* Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2):

AVNIR-2 is a visible and near infrared radiometer for observing land and coastal zones.

It provides 10-m spatial-resolution image and 70-km swath on the ground. The pointing angle of AVNIR-2 is +44 and - 44 degrees. This image was acquired by 15 degrees east.

JAXA EORC