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Direct Broadcast views of high AOD values over North America

VIIRS data downloaded from the CIMSS Direct Broadcast antenna (the link is evanescent) is used to create imagery that shows poor air quality over North America. The toggle above compares Aerosol Optical Depth and True-Color imagery derived using CSPP software. Two main smoke plumes are apparent, one stretching from northern Canada south and eastward... Read More

VIIRS data downloaded from the CIMSS Direct Broadcast antenna (the link is evanescent) is used to create imagery that shows poor air quality over North America. The toggle above compares Aerosol Optical Depth and True-Color imagery derived using CSPP software. Two main smoke plumes are apparent, one stretching from northern Canada south and eastward to the Great Lakes, and a second over the southern Gulf of Mexico/Yucatan Peninsula.

Aerosol Optical Depth (AOD) and True-Color imagery derived from VIIRS imagery, ca. 1940 UTC on 12 May 2024 (Click to enlarge)

Very large full-resolution images from the CIMSS Direct Broadcast site are available for true-color and AOD imagery. (Click the links)


A GOES view of some of this smoke is available here.

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Wildfires in British Columbia

10-minute Full Disk sector GOES-18 (GOES-West) Day Land Cloud Fire RGB, Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.3 µm) and “Red” Visible (0.64 µm) + Fire Power derived product (a component of the GOES Fire Detection and Characterization Algorithm FDCA) images (above) showed signatures of multiple wildfires across northeastern British Columbia on 10 May 2024 — including the Parker Lake Fire... Read More

GOES-18 Day Land Cloud Fire RGB (top left), Shortwave Infrared (3.9 µm, top right), “Clean” Infrared Window (10.3 µm, bottom left) and “Red” Visible (0.64 µm) + Fire Power derived product (bottom right), from 1500 UTC on 10 May to 0120 UTC on 11 May [click to play animated GIF | MP4]

10-minute Full Disk sector GOES-18 (GOES-West) Day Land Cloud Fire RGB, Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.3 µm) and “Red” Visible (0.64 µm) + Fire Power derived product (a component of the GOES Fire Detection and Characterization Algorithm FDCA) images (above) showed signatures of multiple wildfires across northeastern British Columbia on 10 May 2024 — including the Parker Lake Fire located NW of Fort Nelson (CYYE), which forced the evacuation of 3200 residents as the head of the wind-driven fire approached the city.

A cursor sample of GOES-18 imagery at 2140 UTC on 10 May (below) indicated a Shortwave Infrared (3.9 µm) brightness temperature of 135.81ºC — which is only 2.7ºC less than the saturation temperature of GOES-18 ABI Band 7 detectors  — and a rather high Fire Power derived product value of 5478..81 MW associated with the Parker Lake Fire.

Cursor sample of GOES-18 Day Land Cloud Fire RGB (top left), Shortwave Infrared (3.9 µm, top right), “Clean” Infrared Window (10.3 µm, bottom left) and “Red” Visible (0.64 µm) + Fire Power derived product (bottom right) at 2140 UTC on 10 May [click to enlarge]

GOES-18 daytime True Color + Nighttime Microphysics RGB images from the CSPP GeoSphere site (below) displayed the dense plumes of wildfire smoke (after sunset, the fire thermal anomalies showed up as clusters of darker purple in Nighttime Microphysics RGB imagery). Intermittent pulses of brighter-white pyrocumulus clouds were evident over the larger, more intense wildfires.

GOES-18 daytime True Color + Nighttime Microphysics RGB images, from 1300 UTC on 10 May to 0410 UTC on 11 May [click to play MP4 animation]

A 30-meter resolution Landsat-8 Natural Color RGB image at 1917 UTC on 10 May, viewed using RealEarth (below) provided a detailed look at the Parker Lake Fire burn scar (shades of brown) and an area of active burning (brighter shades of pink to red), along with pyrocumulus clouds produced by the fire. The other large wildfire east of Fort Nelson was apparent.

Landsat-8 Natural Color RGB image at 1917 UTC on 10 May [click to enlarge]

A nighttime Suomi-NPP VIIRS Shortwave Infrared (3.74 µm) image valid at 0957 UTC on 11 May (below) revealed the ~40 mile northwest-to-southeast run of the Parker Lake Fire (just to the NW and N of CYYE) — driven by NW winds gusting as high as 34 kt (CYYE surface reports) behind a fast-moving cold front (surface analyses).

Suomi-NPP VIIRS Shortwave Infrared (3.74 µm) image valid at 0957 UTC on 11 May [click to enlarge]

After sunrise on 11 May, GOES-16 (GOES-East) True Color RGB images (below) showed the hazy gray-to-tan signature of widespread smoke from the British Columbia (and Prairie Province) wildfires — some of which became entrained into the circulation of a low pressure system in the Northwest Territories, with other plumes being transported as far east as Hudson Bay and as far south as North Dakota, South Dakota, Minnesota, Wisconsin, Michigan and Illinois.

GOES-16 daytime True Color + Nighttime Microphysics RGB images, from 1130 UTC on 11 May to 0000 UTC on 12 May [click to play MP4 animation]

Note that the hazy signature of wildfire smoke was quite pronounced (in GOES-16 True Color RGB imagery) over southern Wisconsin by the end of the day on 11 May — lidar data from the University of Wisconsin – Madison (source) confirmed the presence of smoke aloft within the 4-6 km altitude range, from about 1800 UTC on 11 May to 0000 UTC on 12 May (below).

Lidar 532 nm Backscatter (top) and Linear Depolarization (bottom) at Madison Wisconsin [click to enlarge]

 

Lidar 1064/532 nm Aerosol Backscatter Ratio (top) and 1064/532 Combined Count Ratio (bottom) at Madison, Wisconsin [click to enlarge]

===== 12 May Update =====

GOES-16 daytime True Color + Nighttime Microphysics RGB images, from 1130 UTC on 12 May to 0010 UTC on 13 May [click to play MP4 animation]

GOES-16 True Color RGB images (above) showed that the areal coverage of dense smoke increased across much of the north-central US on 12 May. Air Quality Advisories were issued for parts of the Upper Midwest.

The GOES-16 Aerosol Optical Depth (AOD) derived product with plots of Ceiling and Visibility (below) displayed AOD values as high as 1.0 to 1.6 (darker shades of red) across parts of far southern Canada and the north-central US — and the surface visibility dropped to 3 miles or less due to smoke at some sites from Montana to Minnesota.

GOES-16 Aerosol Optical Depth derived product with plots of Ceiling and Visibility, from 1236-2356 UTC on 12 May [click to play animated GIF | MP4]

Aerosol Optical Depth derived from an overpass of NOAA-20 VIIRS data can be viewed in this blog post.

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Aurora over the northern United States

The Space Weather Prediction Center (link) has recently noted strong solar activity as part of the ongoing solar maximum (see the images below from 10 May and 11 May). The result on 11 May was an aurora borealis observed south into the United States. The Day Night Band image above,... Read More

VIIRS Day Night Band over the central United States showing an Aurora, 0813 UTC 11 May 2024 (Click to enlarge)

The Space Weather Prediction Center (link) has recently noted strong solar activity as part of the ongoing solar maximum (see the images below from 10 May and 11 May). The result on 11 May was an aurora borealis observed south into the United States. The Day Night Band image above, from Suomi-NPP, shows the light of the Aurora stretched out like a necklace across the northern United States. (Additional views of Day Night imagery are available at VIIRS Today showing NOAA-20 and Suomi NPP and at the VIIRS Imagery Viewer that also includes NOAA-21 Day Night Band imagery). Imagery is also available at the CIMSS Direct Broadcast site.

G5 Alert issued by SWPC, 2330 UTC on 10 May 2024 (Click to enlarge)
SWPC notice of a strong solar flare at 0123 UTC on 11 May 2024 (Click to enlarge)

Day Night Band imagery along the east and west coasts (below) show how the character of the auroral display changed during the night.

Suomi-NPP VIIRS Day Night Band imagery, 0659 UTC on 11 May 2024 (Click to enlarge)
Suomi-NPP VIIRS Day Night Band imagery, 0956 UTC on 11 May 2024 (Click to enlarge)

A strong Aurora australis also occurred on 11 May (link).

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NOAA-21 NUCAPS Profiles (and gridded NUCAPS fields) are now in AWIPS

NUCAPS profiles from NOAA-21 are now flowing into AWIPS, joining NUCAPS from NOAA-20 and Metop-C. NOAA-21 and NOAA-20 orbits are similar, and the combination of the two satellites means complete coverage twice daily. That is demonstrated in the animation above over Hawai’i that shows gridded NUCAPS fields of 500-mb temperatures... Read More

Gridded NUCAPS values of 500-mb Temperatures from three different overpasses near 1200 UTC on 10 May 2024 (Click to enlarge)

NUCAPS profiles from NOAA-21 are now flowing into AWIPS, joining NUCAPS from NOAA-20 and Metop-C. NOAA-21 and NOAA-20 orbits are similar, and the combination of the two satellites means complete coverage twice daily. That is demonstrated in the animation above over Hawai’i that shows gridded NUCAPS fields of 500-mb temperatures between 1134 and 1331 UTC on 10 May 2024, from two NOAA-21 overpasses and one NOAA-20 overpass. There are no gaps in data coverage! The data shows unseasonably cold 500-mb temperatures (-16oC) to the north of the Hawai’ian Islands. The cold temperatures are associated with a region of convection to the north of Hawai’i as shown in the image below taken from the Geosphere site.

True-color imagery over Hawai’i, 1830 UTC on 10 May 2024 (click to enlarge)

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