Autumn colors evident on MODIS true color imagery
A sequence of three Terra MODIS true color images from 02 August, 30 August, and 22 September 2007 centered over Lake Superior (above) reveals the onset of the brilliant orange Autumn season tree colors across parts of northeastern Minnesota, the Upper Peninsula of Michigan, and northern Wisconsin (ground truth: photo 1 | photo 2). Much of that area has experienced moderate to severe drought conditions, which could be causing the trees to begin to change color a bit earlier than normal due to stress.
Farther to the south, a similar sequence of three MODIS images centered over the state of Wisconsin (below) shows another (unrelated) change of colors — note the change from green to light brown colors across southern parts of the region where trees are sparse and corn cultivation is prevalent (southeastern Minnesota, northeastern Iowa, and northern Illinois). Once the majority of the corn fields begin to mature and dry down leading up to harvest time, those areas begin to take on a light brown hue on the MODIS true color imagery.
In addition, note the hazy appearance across a good deal of the southern half of the first MODIS image below (on 02 August) — this was due to thick smoke from widespread wildfires that had been burning in Idaho and Montana (IDEA MODIS Aerosol Optical Depth). This thick smoke had been lingering over the northern Rocky Mountain region during the last few days of July 2007, and was then transported eastward and concentrated along a cold frontal boundary that moved across the Great Lakes region on 02 August.
The image below shows a zoomed-in view centered on Lake Gogebic (located in the western portion of the Upper Peninsula of Michigan) on 23 September, using the AWIPS MODIS True Color Imagery Viewer developed by Jordan Gerth at CIMSS. This tool allows National Weather Service forecasters to view MODIS true color imagery within the AWIPS environment.
