Submitted by shyun on Fri, 01/15/2016 - 13:56
Download flood extent maps at http://aria-share.jpl.nasa.gov/events/20160111-US_Midwest_Floods/
In response to the December 2015 - January 2016 US Midwest Floods along the Mississippi River, the ARIA project produced flood extent maps derived from Synthetic Aperture Radar data of ALOS-2 satellite operated by Japanese Aerospace Exploration Agency's (JAXA). The maps are available in four different data types - KMZ files with PNG images, KMZ files with polygons, GeoTiff files, and Shapefiles. The KMZ files have three different layers - blue, red, and transparent. The blue and red colors represent areas of potential floods, and blue is likely due to rough surface replaced with smooth water (or open water), whereas the red likely due to floods in the areas with tall vegetation that enhanced the double bouce of radar signal. The GeoTiff and Shapefile are composed of two files for each frame that represent open water (*open.tif/shp) and vegetated water (*veg.tif/shp). These maps were not validated with independent observations such as optical imagery or ground observations. The figure below shows an area including the City of Memphis. The map was created by comparing a pre-flood (2015-09-30) and during-the-flood (2016-01-06) SAR scenes. Depending on the irrigation condition of the agricultural lands on those dates, there may be false positives.
This flood extent maps should be used as guidance to identify flooded areas, and may be less reliable over urban areas. Original data ALOS-2 PALSAR-2 Product - ©JAXA (2016). All Rights Reserved.