No Northern Lights, but Plenty of Southern Shadows
Posted 1 day ago

Today’s total eclipse may have missed Alaska, but weather satellites had a great view.  Here is a loop from the new GOES-16 satellite showing the moon’s shadow zipping across the Lower 48.  


This imagery is a combination of three channels ranging from visible light into the near infrared spectrum, and these wavelengths all have one thing in common: they respond to sunlight bouncing off of the clouds, land, and ocean.  When the moon briefly blocks out the sun, such as during today’s eclipse, these is no sunlight to bounce of the targets below, and thus briefly darkness becomes visible.

GINA works with the satellite proving ground community to bring the newest tools and techniques in satellite meteorology to forecasters working with the National Weather Service and others.  You may note that Alaska is not covered in this imagery, as the longitude at which GOES-16 hovers is simply too far east to allow a good look at Alaska.  But worry not: GOES-17 will be in orbit within another year or two, and at a longitude far enough west to provide a great view of Alaska (and Hawaii, for that matter).  Today’s imagery from GOES-16 offers Alaskans a preview of the improvements yet to come.

This loop, and the website hosting this very nice interface for interrogating all kinds of imagery from the GOES-16 satellite, is maintained by the professionals at the Cooperative Institute for Research in the Atmosphere (CIRA) in Colorado.