Category 4 Hurricanes Kilo, Ignacio, and Jimena in the Pacific Ocean

August 30th, 2015

Suomi NPP VIIRS true-color image composite [click to enlarge]

Suomi NPP VIIRS true-color image composite [click to enlarge]

A composite of Suomi NPP VIIRS true-color Red/Green/Blue (RGB) images from the SSEC RealEarth site (above; click to enlarge) showed Hurricanes Kilo, Ignacio, and Jimena in the central and eastern North Pacific Ocean on 29 August 2015. All three of these Category 4 North Pacific hurricanes were located east of the International Dateline, which is the first such occurrence since reliable records began in the satellite era.

An animation of GOES-15 (GOES-West) Infrared (10.7 µm) images (below; click image to play animation) showed the evolution of these 3 tropical cyclones during the 29-30 August period.

GOES-15 Infrared (10.7 µm) images [click to play animation]

GOES-15 Infrared (10.7 µm) images [click to play animation]

The MIMIC Total Precipitable Water product (below; click image to play animation) indicated that all 3 storms were easily able to tap abundant moisture from the Intertropical Convergence Zone (ITCZ).

MIMIC TPW product [click to play animation]

MIMIC TPW product [click to play animation]

A longer animation of the MIMIC TPW product covering the period 21 August to 01 September is shown below.

MIMIC Total Precipitable Water product [click to play animation]

MIMIC Total Precipitable Water product [click to play animation]

Eruption of the Cotopaxi volcano in Ecuador

August 14th, 2015

GOES-13 visible (0.63 µm) images [click to play animation]

GOES-13 visible (0.63 µm) images [click to play animation]

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.

GOES-13 infrared (10.7 µm) images [click to play animation]

GOES-13 infrared (10.7 µm) images [click to play animation]

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.

 GOES-13 water vapor (6.5 µm) images [click to play animation]

GOES-13 water vapor (6.5 µm) images [click to play animation]

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.

Aqua MODIS true-color images [click to enlarge]

Aqua MODIS true-color images [click to enlarge]

Suomi NPP VIIRS true-color image [click to enlarge]

Suomi NPP VIIRS true-color image [click to enlarge]

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.

Suomi NPP VIIRS visible (0.64 µm) and infrared (11.45 µm) images [click to enlarge]

Suomi NPP VIIRS visible (0.64 µm) and infrared (11.45 µm) images [click to enlarge]

Explosion in Tianjin, China

August 12th, 2015

Himawari-8 (3.9 µm, top), MTSAT-2 (3.75 µm, middle) and COMS-1 (3.75 µm, bottom) shortwave infrared imagery, times as indicated [click to animate]

Himawari-8 (3.9 µm, top), MTSAT-2 (3.75 µm, middle) and COMS-1 (3.75 µm, bottom) shortwave infrared imagery, times as indicated [click to animate]

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.

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to enlarge]

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to animate]

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to animate]

Himawari-8 1.6 µm near-Infrared Imagery, times as indicated [click to animate]

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.

Himawari-8 shortwave IR (3.9 um) images, displayed using RealEarth [click to enlarge]

Himawari-8 shortwave IR (3.9 um) images, displayed using RealEarth [click to enlarge]


========================== 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]

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.

Ice in Hudson Bay, Canada

August 7th, 2015

GOES-13 visible (0.63 µm) images [click to play animation]

GOES-13 visible (0.63 µm) images [click to play animation]

GOES-13 visible (0.63 µm) images (above; click image to play animation; also available as an MP4 movie file) revealed a large amount of ice remaining in southern and eastern portions of Hudson Bay, Canada on 07 August 2015. The ice can be seen “sloshing” back and forth during the day as winds and/or water currents moved it around.

The discrimination of ice vs supercooled water droplet clouds can be made by comparing Terra MODIS true-color and false-color Red/Green/Blue (RGB) images at 1611 UTC (below). On the false-color image, ice (and glaciated clouds with a high concentration of ice crystals at cloud top) appeared as darker shades of red, in contrast to supercooled water droplet clouds which appeared as varying shades of white to cyan.

Terra MODIS true-color and false-color images [click to enlarge]

Terra MODIS true-color and false-color images [click to enlarge]

A Suomi NPP VIIRS true-color image as visualized using the SSEC RealEarth web map server (below) showed the ice at 1800 UTC; even greater detail can be seen in this zoomed-in version of the image.

Suomi NPP VIIRS true-color image [click to enlarge]

Suomi NPP VIIRS true-color image [click to enlarge]


Maps from from the Canadian Ice Service (below) indicated that the concentration of this thick first-year ice (dark green) was still as high as 9/10ths to 10/10ths (red) on 07 August; on 03 August, the ice concentration departure from normal was as high as +9/10ths to +10/10ths (dark blue) in some locations.

Hudson Bay ice concentration [click to enlarge]

Hudson Bay ice concentration [click to enlarge]

Hudson Bay ice stage [click to enlarge]

Hudson Bay ice stage [click to enlarge]

Hudson Bay ice concentration departure from normal [click to enlarge]

Hudson Bay ice concentration departure from normal [click to enlarge]