GOES-11 IR images

Hurricane Celia became the first Category 5 tropical cyclone of the 2010 East Pacific season on 24 June — in fact, the 140 knot intensity of Celia tied with Hurricane Ava (1973) as the strongest East Pacific Basin hurricane on record during the month of June. GOES-11 IR images from the CIMSS Tropical Cyclones site (above) displayed an annular structure with a well-defined small diameter eye as the hurricane began to slowly weaken on 25 June 2010.

85 GHz microwave imagery from the SSM/I instrument (below) also revealed the nearly symmetric structure of the eye of the Celia.

SSMI/S 85 GHz microwave imagery

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Terra MODIS 11.0 µm IR image

McIDAS images of Terra MODIS 11.0 µm IR channel data (above) showed the well-defined eye of Celia during the pre-dawn hours on 25 June, while GOES-11 0.65 µm visible channel images (below) show the evolution of the eye later in the day.

GOES-11 0.65 µm visible images

On the previous day (24 June) — as Celia was rapidly intensifying (CIMSS ADT plot) — the tropical cyclone exhibited  IR brightness temperature values as cold as -91º C at 07:30 UTC on GOES-11 10.7 µm IR images (below).

GOES-11 10.7 µm IR images

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MODIS true color (using bands 1/4/3) and false color (using bands 7/2/1) RGB images

A comparison of 250-meter resolution MODIS true color (created using bands 1/4/3) and false color (created using bands 7/2/1) images on 25 June 2010 from the SSEC MODIS Today site (above) showed the extent of the surface oil slick from the Deepwater Horizon offshore oil rig accident.

AWIPS images of early morning POES AVHRR 0.63 µm visible and 3.7 µm shortwave IR data (below) revealed a thin smoke plume drifting northwestward from a small fire hot spot (orange color enhancement) due to a fire that was set to burn off some of the surface oil.

POES AVHRR 0.63 µm visible and 3.7 µm shortwave IR images

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GOES-13 0.63 µm visible images

AWIPS images of GOES-13 0.63 µm visible channel data (above) showed widespread hazy conditions over much of the Great Lakes region during the afternoon and evening hours on 24 June 2010. The thick haze became more evident during the late afternoon and early evening hours, as a more favorable sun angle for “forward scattering” helped to highlight the airborne aerosols.

The MODIS Aerosol Optical Depth (AOD) product (below) indicated that AOD values over much of the Great Lakes region were in the 0.6 to 0.8 range, with a larger area of AOD values near 1.0 over south-central Canada. A large number of wildfires had been burning across the northern Prairie Provinces of Canada during the preceding days — so could this thick haze seen over the Great Lakes be due to smoke from Canadian fires?

MODIS Aerosol Optical Depth (AOD) product

A comparison of 1-km resolution MODIS 0.65 µm visible and 3.7 µm shortwave IR images (below) depicted a number of smoke plumes and “hot spots” (orange to yellow color enhancement) from fires that were still burning on 24 June over northern Saskatchewan and Manitoba. However, on this day, surface winds were from the southeast, advecting the smoke plumes toward the northwest.

MODIS 0.65 µm visible channel and 3.7 µm shortwave IR images

A comparison of the 1-km resolution MODIS and AVHRR 3.7 µm shortwave IR images with the corresponding 4-km resolution GOES-13 3.9 µm shortwave IR image (below) demonstrated the improvement in fire hot spot detection and geo-location using the 1-km resolution polar orbiting satellite data — note the mapping errors on the GOES-13 image due to the large viewing angle from the geostationary satellite.

MODIS 3.7 µm, AVHRR 3.7 µm, and GOES-13 3.9 µm shortwave IR images

Over southern Wisconsin, the thick smoke contributed to colorful yellow to orange sunset, as seen using the AOSS rooftop camera at the University of Wisconsin – Madison (below; also available as a QuickTime animation).

AOSS rooftop camera image (facing to the west)

Lidar data from the UW-Madison SSEC Lidar Group (below) showed enhanced backscatter within the 1-2 km altitude layer during the daytime hours.

Lidar backscatter data from the SSEC Lidar Group at UW-Madison

NOAA ARL HYSPLIT back trajectories (below) confirmed that air parcels arriving over Madison, Wisconsin on 24 June had likely passed over the parts of northern Saskatchewan 2-3 days earlier, where active fires had been burning for several days.

NOAA ARL HYSPLIT backward trajectories (arriving over Madison, Wisconsin)

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MODIS true color and false color RGB images

The comparison of a 250-meter resolution MODIS true color Red/Green/Blue (RGB) image (created using Bands 1/4/3) with the corresponding MODIS false color (created using Bands 7/2/1) image from the SSEC MODIS Today site (above) showed intricate details of the surface oil slick in the far northern Gulf of Mexico on 19 June 2010. The glaciated cloud tops of deep convection appeared as darker shades of cyan on the false color image.

On the true color image, note the small black features located over the bright oil slick, toward the lower left portion of the image — this was smoke from small fires which were apparently being set to burn off some of the surface oil (the fire hot spots show up as shades of pink on the false color image). This was Day 61 following the explosion of the Deepwater Horizon offshore oil rig on 20 April.

The MODIS true color image displayed using Google Earth (below; courtesy of Liam Gumley, CIMSS) offers a different perspective and a larger-scale view of the oil slick.

MODIS true color image (displayed using Google Earth)

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