The Visible-Infraread Imager Radiometer Suite (VIIRS) instrument on Suomi/NPP samples longwave radiation emitted at 11.45 µm and shortwave radiation emitted at 3.74 µm. Because liquid water clouds have different emissivity properties at those two wavelengths, the difference in brightness temperature can be used to determine the presence of clouds (such... Read More
The Day-Night Band from VIIRS on the Suomi/NPP has been giving excellent imagery of Tropical Storms Ernesto and Florence over the weekend. The views are especially crisp because of the near fullness of the moon. For example, the sheared nature of Ernesto (top) is evident, and the overshooting tops in... Read More
A strong tropical wave near 50 W Longitude in the central Atlantic has become a Tropical Depression. The enhanced infrared image above shows a region of active convection (as signified by the overshooting tops designated by yellow circles) near the center of the system. (Current imagery of overshooting tops can... Read More
Persistent heat over the upper Midwest and Eastern United States for the first half of 2012 have helped warm Great Lakes surface water temperatures. MODIS estimates of Lake Surface temperature, above, show only a small region of temperatures cooler than 60 F in the entire Lake system in a very... Read More
