Emergency Observation of mudslides in Mexico by AVNIR-2 onboard "Daichi" (ALOS)
Southern Mexico was seriously damaged by mudslides on September 28, 2010, which were caused by heavy rain which continuously had occurred since September 9, 2010. 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 16:37 (JST) or 7:37 (UTC) on September 29, 2010.Fig. 1 shows an observed image and is assigned band 3, 2 and 1 of AVNIR-2 as the true color composite. White colored areas show clouds, however some ground surface could be seen through the clouds.
Figs. 2 and 3 are comparison of images taken after and before disaster, located at San Pablo Villa de Mitla and Santa Maria Tlahuitoltepec, respectively. They are assigned band 4, 3 and 2 of AVNIR-2 as the false color composite, therefore vegetation can be seen in red color and areas where vegetation is lost due to mudslides.Yellow circles indicate vegetation was lost and mudslides occurred because of the reduced red color 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 21.0 degrees west. The image taken before disaster on May 4, 2009 and August 7, 2010 were acquired by 0.0 degree.