MTSAT « CIMSS Satellite Blog

Earth Day 2013

April 22nd, 2013

Global composite of geostationary IR images at 12:00 UTC (click image to play animation)

In honor of Earth Day, we offer a glimpse of the cloud cover across the planet, using a rotating global composite of geostationary IR images (data from the GOES-East, GOES-West, Meteosat, and MTSAT satellites) at 12:00 UTC on 22 April 2013 (above; click image to play animation). The most recent rotating global IR composite (updated every 3 hours) can be seen here.

Global composite of IR imagery, land surface temperature, and sea surface temperature (click image for most recent animation)

Other global satellite image composites created at SSEC include IR, surface air temperature, and sea surface temperature (above; click image for most recent animation) and water vapor channel imagery (below; click image for most recent animation).

Global composite of water vapor imagery (click image for most recent animation)

Posted in General interpretation, GOES-13, GOES-15, Meteosat, MTSAT | No Comments »

Volcanic ash fall plume over the Kamchatka Peninsula

March 7th, 2013

Suomi NPP VIIRS 0.64 µm visible channel images

AWIPS images of Suomi NPP VIIRS 0.64 µm visible channel images (above) revealed some interesting curved ice floe gyres in the Bering Sea just off the eastern coast of the Russian Kamchatka Peninsula on 07 March 2013. Also evident near the center of the visible images was a long, narrow, and slightly darker feature that was oriented approximately west-to-east, and located to the northwest and north of the village of Ust’-Kamchatsk (station identifier 32408). This darker feature was a volcanic ash fall plume from the Sheveluch Volcano (located 31 miles or 50 km to the northwest), which had experienced eruptions producing volcanic ash (photos) on 02 March and 04 March — the darker color of the narrow strip of volcanic ash made it stand out against the adjacent snow-covered areas (annotated visible image).

A comparison of a Suomi NPP VIIRS 0.64 µm visible channel image with the corresponding false-color Red/Green/Blue (RGB) image (below) also showed the contrast between the narrow strip of ash-covered snow and the surrounding undisturbed snow cover (snow and ice appear as darker shades of red in the RGB image).

Suomi NPP VIIRS 0.64 µm visible channel image + False-color Red/Green/Blue (RGB) image

A comparison of Suomi NPP VIIRS 0.64 µm visible channel, 3.74 µm shortwave IR channel, and 11.45 µm IR channel images (below) showed that the strip of ash-covered snow appeared significantly warmer (darker) on the shortwave IR image, due to the fact that the volcanic ash particles were efficient reflectors of incoming solar radiation. The ash-covered snow even appeared slightly warmer (darker) on the 11.45 µm IR image, since the lower albedo of the ash-covered snow allowed it to absorb more incoming solar radiation.Also evident on the shortwave IR image was a distinct hot thermal anomaly (yellow to red color enhancement) associated with the active Kizimen volcano.

Suomi NPP VIIRS 0.64 µm visible channel, 3.74 µm shortwave IR channel. and 11.45 µm IR channel images

An animation of McIDAS images of MTSAT-2 0.73 µm visible channel data (below; click image to play animation) confirmed that the darker volcanic ash fall plume was a stationary feature, and not an airborne volcanic ash plume. The animation also showed the anticyclonic rotation of the gyres of ice floes just off the east coast of Kamchatka.

MTSAT-2 0.73 µm visible channel images (click image to play animation)

Posted in Arctic, MTSAT, Red/Green/Blue (RGB) images, Suomi NPP, VIIRS, Volcanic activity | No Comments »

Polar low over the western Bering Sea

March 3rd, 2013

Suomi NPP VIIRS 0.7 µm Day/Night Band images

AWIPS images of 1-km resolution Suomi NPP VIIRS 0.7 µm Day/Night Band data (above) showed the development of a small polar low in the far western Bering Sea during the 02 March – 03 March 2013 period. A string of breaking Kelvin-Helmholtz waves could be seen feeding into the circulation of the developing low. Station identifiers 25941, 25954, and 21956 denote the villages of Cemurnaut, Korf, and Apuka (respectively) located on the northern end of the Kamchatka Peninsula of Russia.

The corresponding Suomi NPP VIIRS 11.45 µm IR channel images (below) indicated that cloud top IR brightness temperatures were colder than -30º C (darker blue color enhancement) near the center of the polar low circulation.

Suomi NPP VIIRS 11.45 µm IR channel images

Suomi NPP VIIRS false-color Red/Green/Blue (RGB) images (below) showed that the polar low was developing just south of the sea ice edge (snow and ice appear as darker shades of red). The appearance of red shading also indicated that the cloud tops along the string of Kelvin-Helmholtz waves were beginning to glaciate. Note from the distance scale plotted on the lower left that the diameter of the polar low circulation was less than 100 miles.

Suomi NPP VIIRS false-color Red/Green/Blue (RGB) images

A larger-scale view using a Suomi NPP VIIRS 0.64 µm visible channel image (below) helped to emphasize the small size of the Bering Sea polar low, especially when compared to the much larger storm system that was located just south of the Aleutian Islands at that time. The tightly-packed isobars of another strong storm approaching from the North Pacific Ocean could also be seen.

Suomi NPP VIIRS 0.64 µm visible channel image + Surface reports and surface analysis

McIDAS images of MTSAT-2 0.73 µm visible channel data (below; click image to play animation) indicated that the polar low was initially moving southeastward away from the Kamchatka Peninsula, but then began to reverse direction and move back northwestward due to strong southeasterly flow in advance of the large and intense storm over the North Pacific Ocean.