GOES-13 visible (0.63 µm) images (above; click to play animation) displayed distinct dark-gray ash plumes from 2 separate daytime eruptions of the Cotopaxi volcano in Ecuador on 14 August 2015 (there was also an initial eruption that occurred during the preceding nighttime hours). The asterisk near the center of the images marks the location of the volcano summit. Volcanic ash fall was observed in the capitol city of Quito (station identifier SEQU, located about 50 km or 30 miles north of the volcano), and some flights were diverted due to the volcanic ash cloud.

The corresponding GOES-13 infrared (10.7 µm) images (below; click image to play animation) showed that cloud-top IR brightness  temperatures were as cold a -53º C (orange color enhancement) at 1915 UTC.

The volcanic cloud features were also easily tracked on GOES-13 water vapor (6.5 µm) images (below; click image to play animation). In fact, note how the signature in the water vapor imagery is more distinctly seen for a longer period of time than on the 10.7 µm infrared imagery.

The tan-colored volcanic ash cloud was also evident on Aqua MODIS and Suomi NPP VIIRS true-color Red/Green/Blue (RGB) imagery (below), as viewed using the SSEC RealEarth web map server.

A comparison of Suomi NPP VIIRS visible (0.64 µm) and infrared (11.45 µm) images is shown below (courtesy of William Straka, SSEC). The coldest cloud-top IR brightness temperature was -72.7º C.

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A storage facility in Tianjin, China exploded shortly after 1500 UTC on 12 August 2015 (media story). Himawari-8, MTSAT-2 and COMS-1 all viewed the explosion that generated a strong thermal signature in the shortwave infrared band (3.75 µm – 3.9 µm). The animation above shows the benefit of Himawari-8’s speedier scanning mode: the smoke clouds that emanate from the explosion are easily traced, and data gaps when Full Disk images are being scanned (around 1800 UTC) are not present. Superior spatial resolution of Himawari-8 infrared channels (2-km, compared to 4-km for COMS-1 and MTSAT-2) means hotter brightness temperatures are sensed as well. The fact that smoke resulting from the explosion was seen spreading northeastward, southeastward, and southwestward was due to a marked shift in wind direction with height, as seen in the nearby Beijing rawinsonde report.

The explosion exhibted a signal in other Himawari-8 AHI bands as well. Band 5, at 1.6 µm and Band 6, at 2.3 µm are shown below (animations courtesy of William Straka, CIMSS); Similar animations are available for 3.9 µm, 6.2 µm (very faintly visible in this upper tropospheric water vapor channel), 7.0 µm, 7.3 µm and 8.6 µm and 10.35 µm.

A view of Himawari-8 shortwave IR imagery using the SSEC RealEarth web map server is shown below. In addition, an animation of Himawari-8 true-color images showing the dark smoke plume can be seen here.

========================== Added 14 August 2015 ===================

Suomi NPP VIIRS Day/Night Band (0.70 um) visible images on 9 August (before explosion) and 13 August (after explosion) [click to enlarge]

The Suomi NPP satellite overflew Tianjin before and after the explosion; VIIRS Day/Night Band images afford views that suggest power outages around the explosion site.

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1-minute interval GOES-14 SRSO-R visible (0.63 µm) images (above; click image to play animation) revealed the pulsing nature of the large Cougar Creek wildfire complex burning in southern Washington (not far southwest of Yakima) on 12 August 2015. The MP4 movie file is also available as a very large (128 Mbyte) animated GIF. The second fire blow-up that began around 1700 UTC apparently produced a pyrocumulonimbus cloud, with cloud-top IR Brightness Temperature (BT) values cooling past -40º C. Large amounts of smoke were transported northward and then northeastward away from the fire source region.

During the preceding overnight hours, a comparison of  1003 UTC Suomi  NPP VIIRS shortwave Infrared (3.74 µm), Day/Night Band (0.8 µm), and Infrared (11.45 µm) images (below) showed a very large shortwave IR fire “hot spot” (yellow to red to black pixels), with the large fire glowing very brightly on the Day/Night Band image; the coldest IR BT value of the cloud streaming northward from the fire was -53º C.

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A nighttime mesoscale convective system (MCS) developed near the Arkansas/Louisiana/Mississippi border region after about 0700 UTC (2:00 AM local time) on 11 August 2015, and began to move southeastward. A comparison of 4-km resolution GOES-13 Infrared (10.7 µm) and 375-meter resolution Suomi NPP VIIRS Infrared (11.45 µm) images (above) showed the MCS around 0845 UTC, and highlighted the two advantages of polar-orbiter vs geostationary satellite imagery: (1) higher spatial resolution, for a more accurate assessment of the cloud-top IR Brightness Temperatures (the coldest GOES-13 IR BT was -73º C, while the coldest VIIRS IR BT was -83º C), and (2) minimal parallax error, for a more accurate geo-location of features such as thunderstorm overshooting tops (note how the storm appeared to be located farther to the northwest on the GOES image, centered over far southeastern Arkansas).

With the arrival of daylight the following morning, 1-minute interval GOES-14 SRSO-R visible (0.63 µm) images (below) revealed the presence of numerous short-lived overshooting tops which were penetrating the cirrus canopy of the persisting MCS. The formation of a well-defined outflow boundary was also seen, which continued to move southward during the late morning hours. The MP4 movie file is also available as a very large (73 Mbyte) animated GIF. A GOES-14 1-minute-image IR (10.7 µm) animation which shows the initial development and subsequent motion of the MCS can be seen here.

GOES-14 1-minute visible images (below) also showed the development of multi-cellular thunderstorms over parts of the Mid-Atlantic states, focused along trough axes ahead of an approaching cold frontal boundary — many of these thunderstorms produced damaging winds (SPC Storm Reports). The MP4 movie file is also available as a very large (102 Mbyte) animated GIF.

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