Earth Orbiting Satellites Page 4 of 6 Natural hazard monitoring As many natural hazards are linked to meteorological extreme events, meteorological satellite images can often provide the first warning of hazards. For example, the presence of a cloud system that causes heavy and prolonged rainfall could lead to flooding. Whereas, areas that show evidence of long periods of rain free weather on cloud free images, along with evidence of a vegetation response on the image, could give prior warning to drought or the risk of bush fire. NOAA images have been used to capture floods, giving an almost real time monitoring of the extent of devastation caused by the event. Click on the thumbnails to enlarge the images   Image 1 (after the flood) Image 2 (before the flood)   These two NOAA 14 AVHRR images are of the Sacramento Valley, California, image 1 was taken on January 5, 1997 and the swollen Sacramento and Feather Rivers are clearly visible in the image (green). Compare image 1 to image 2, which was taken on August 1, 1996, before there was any flooding and the rivers are barely visible. The red areas within image 2 represent the fertile valleys with their summer crops. Although the reason for the vegetation being much more prominent in the second image is mainly due to the different times of year when the images were taken. | 1 | 2 | 3 | 4 | 5 | 6 | Page 4 of 6