Typhoon Champi

October 22nd, 2015 |
H8_16PANEL_22October2015_0000_1230anim

16-panel Himawari-8 multispectral animation of Typhoon Champi, half-hourly from 0000-1230 UTC on 22 October. Top row: 0.47µm, 0.51µm, 0.64µm, 0.86µm ; Second Row: 1.6µm, 2.3µm, RGB Composite (daytime)/3.7µm (Nighttime), 6.2µm; Third Row: 6.9µm, 7.3 µm, 8.6 µm, 9.6 µm; Bottom Row: 10.4µm, 11.2 µm, 12.4µm, 13.3µm (Click to enlarge)

Himawari-8 viewed Typhoon Champi in the North Pacific on 22 October 2015, as shown above. The storm was near peak intensity during this animation, as indicated by the graphs of satellite maximum wind speed and minimum surface pressure shown below (taken from this website). The eye (abnormally large for a Typhoon!) of Champi passed just to the south of the island of Iwo Jima, where a wind gust of 72 knots (83 mph) occurred at 09 UTC (surface observations). The Himawari-8 AHI instrument has 16 channels, as will the GOES-R ABI when it is launched in October 2016.

Satellite-estimated maximum wind velocity of Typhoon Champi (click to enlarge)

Satellite-estimated maximum wind velocity of Typhoon Champi (click to enlarge)

H8_16PANEL_22October2015_0000_1230anim

Satellite-estimated minimum surface Mean Sea Level Pressure of Typhoon Champi (Click to enlarge)

The Himawari-8 AHI instrument is also capable of gathering rapid-scan images over specified “Target Areas” every 2.5 minutes; rapid-scan Visible (0.64 µm) images of the eye of Typhoon Champi are shown below (also available as an MP4 animation). The GOES-R ABI will have the capability to scan special mesoscale sectors at 1-minute or even 30-second intervals.

Himawari-8 Visible (0.64 µm) images (click to play animation)

Himawari-8 Visible (0.64 µm) images (click to play animation)

Himawari-8 data — all channels — are routinely available here and here.

Hurricane Olaf

October 20th, 2015 |
Advanced Dvorak Technique (ADT) intensity estimate plot for Hurricane Olaf

Advanced Dvorak Technique (ADT) intensity estimate plot for Hurricane Olaf

A plot of the Advanced Dvorak Technique (ADT) intensity estimate for Hurricane Olaf (above) showed that the storm went through a period of rapid intensification during the 19-20 October 2015 period, reaching Category 4 strength. The National Hurricane Center noted that Olaf became the 6th major hurricane in the eastern North Pacific during the 2015 season, and that this was is the farthest south (9.9º N latitude) that a major hurricane had formed in that ocean basin since reliable records began in 1971 (discussion archive: NHC | CPHC).

4-km resolution GOES-15 (GOES-West) 10.7 µm Infrared channel images during the period of rapid intensification (below) revealed that cloud-top IR brightness temperatures were quite cold (in the -80º to -90º C range, violet colors) early in the day on 19 October, but then warmed a bit into the -70º to -80º C range (black to white shades) on 20 October as the eye became more well-defined.

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

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

A 375-meter resolution Suomi NPP VIIRS Infrared (11.45 µm) image at 10:23 UTC on 20 October (below) hinted at the presence of mesovortices within the eye of Hurricane Olaf.

Suomi NPP VIIRS Infrared (11.45 µm) image [click to enlarge]

Suomi NPP VIIRS Infrared (11.45 µm) image [click to enlarge]

Typhoon Koppu hits the Philippines

October 18th, 2015 |

Himawari-8 Infrared Imagery, 0400-2030 UTC 17 October 2015 [click for mp4 animation]

Himawari-8 Infrared Imagery, 0400-2030 UTC 17 October 2015; 6.2 µm (Upper Left), 6.9 µm (Upper Right), 7.3 µm (Lower Left), 10.35 µm (Lower Right) [click for mp4 animation]

Typhoon Koppu hit the northern Philippines island of Luzon on Saturday 18 October. The 4-panel mp4 animation above (Click here for an animated gif) shows the 3 water vapor infrared channels (6.2 µm, 6.9 µm and 7.3 µm) and the window infrared channel (10.35 µm) from the Himawari-8 satellite. There is value in three water vapor channels because the shorter wavelength (6.2 µm) better captures high-level moisture whereas the longer wavelength better captures mid-level moisture. Cirrus is readily apparent in the 6.2 µm channel; tropical cumulus is more readily apparent underneath cirrus in the 7.3 µm channel. Compare the two channels in this animation, for example, or in this one. The three water vapor channels on Himawari-8 (similar to the 3 that will fly on the GOES-R ABI instrument) give a three-dimensional view of atmospheric moisture. All four channels above show the approach of Koppu towards Luzon, with the ragged eye filling rapidly at landfall.

Morphed Microwave Imagery showing Koppu's Eyewall [click to enlarge]

Morphed Microwave Imagery showing Koppu’s Eyewall [click to enlarge]

The structure of Koppu’s eyewall is depicted above in a 24-hour morphed animation of microwave data (Source, as referred to from here). The nearly complete eyewall rapidly loses its integrity as the storm moves onshore. Total Precipitable Water (below, taken from the MIMIC Total Precipitable Water Site) shows Koppu on the northern edge of the rich moisture source that is the Intertropical Convergence Zone (Typhoon Champi is to Koppu’s east). Notably, the storm stalled over Luzon after making landfall; flooding rainfalls occurred.

MIMIC Total Precipitable Water over the Western North Pacific Basin [click to enlarge]

MIMIC Total Precipitable Water over the Western North Pacific Basin [click to enlarge]

Himawari-8 also captured the evolution of the storm in visible imagery. The full-resolution animation from 0100-0930 UTC on 17 October is shown below (a slower animation is available here). Periodic bursts of deep convection are apparent in the curved bands near the storm center. These convective bursts are better resolved with the 10-minute imagery from Himawari-8 than from 15-minute data from MTSAT-2 (or COMS-1).

Himawari-8 Visible Imagery (0.63) from 0100 through 0930 UTC on 17 October [click to animate]

Himawari-8 Visible Imagery (0.63) from 0100 through 0930 UTC on 17 October [click to animate]

40 Years of GOES Imagery

October 16th, 2015 |
GOES-1 Visible Imagery, 17 January 1983 [click to animate]

GOES-1 Visible Imagery, 17 January 1983 [click to animate]

On October 16, 1975, GOES-A was launched from Cape Canaveral in Florida (NESDIS Link). After achieving orbit, it was renamed GOES-1 and it broadcast its first image on October 25 of that year. The animation (mp4) above is from January 1983, when GOES-1 was operating as GOES-West. GOES-1 was in service for 10 years; it was decommissioned in March of 1985.