Archive for February, 2007

Dust storm and wildfires in Texas

Saturday, February 24th, 2007

GOES-12 visible image

Strong winds gusting to 60-70 mph in the wake of a cold frontal passage on 24 February 2007 caused widespread blowing dust and wildfire activity across much of the Texas panhandle region. GOES-12 visible channel imagery (above; Java animation) showed the development of a large cloud of blowing dust, as well as several smaller smoke plumes to the south of the blowing dust feature. The dust cloud exhibited a pronounced reddish-brown hue on MODIS true color imagery, due to the composition of the soil in the source region near the Texas / New Mexico border. This airborne dust reduced surface visibilities to less than one mile at several locations, causing traffic accidents and even producing brown-colored snow and rain   (NWS Lubbock TX summary).

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GOES-12 3.9µm InfraRed (IR) imagery (below; Java animation) revealed several “hot spots” (black enhancement) due to wildfire activity that also flared up due to the strong winds. Note that one fire (near Killeen TX, station identifier KGRK, bottom center of the image) became hot enough to saturate the GOES-12 3.9µm detectors at 19:32 UTC, causing the brightness temperature to “wrap around” and actually show up as a “cold” pixel (white enhancement).

GOES-12 3.9µm IR image

Changes to GOES-10 Sounder scanning strategy

Monday, February 19th, 2007

GOES-10 sounder coverage

On 18 February 2007 NOAA/NESDIS/OSO implemented a new schedule for GOES-10 sounder scans during house-keeping periods. The previous sounder schedule had spatial gaps between the hourly scan sectors (above), while the new sounder schedule allows for continuous north-to-south coverage of the entire South American continent (below), while making narrower scans. The GOES-10 satellite has been postioned at 60º W longitude to support the Earth Observation Partnership of the Americas (EOPA) project. The latest GOES-10 sounder and imager products are available on the CIMSS GOES Realtime Derived Products site.
GOES-10 sounder coverage