GOES sounder « CIMSS Satellite Blog

GOES-15 temporarily brought out of storage

February 10th, 2021 | Scott Bachmeier

Water Vapor images from GOES-17 (6.9 µm, left) and GOES-15 (6.5 µm, right) [click to play animation | MP4]

Beginning on 06 February 2021, the GOES-15 satellite was brought out of storage for a 14-day period of imaging (as part of its annual checkout activities). On 10 February, a comparison of Water Vapor images from GOES-17 (6.9 µm) and GOES-15 (6.5 µm) showed mountain waves over southeastern Wyoming and central Colorado (above). This comparison helped to highlight some of the improvements in the GOES-R Series, such as

improved spatial resolution with ABI Water Vapor (and other infrared) spectral bands — 2 km at sub-satellite point for GOES-17, vs 4 km at sub-satellite point for GOES-15
improved temporal resolution — 5-minute image interval for GOES-17, vs 15-minute image interval for GOES-15 (except for 30-minute gaps every 3 hours, during Full Disk scans)
more stable image navigation

Multi-panel animations of GOES-15 images from the Imager and Sounder instruments are shown below (credit: Tim Schmit, NOAA/ASPB). In addition, there are animations of GOES-15 Visible and Infrared Window images.

GOES-15 Imager spectral bands [click to play animation | MP4]

GOES-15 Sounder spectral bands [click to play animation | MP4]

GOES-15 data were downloaded, processed and archived by SSEC Satellite Data Services. Real-time GOES-15 imagery is temporarily available here: Imager | Sounder.

Posted in GOES sounder, GOES-15, GOES-17 | No Comments »

GOES-14 is brought out of storage

July 31st, 2019 | Scott Bachmeier

GOES-14 Visible (0.63 µm) images [click to enlarge]

GOES-14 was brought out of storage on 31 July 2019, for its annual week of Image Navigation and Registration (INR) testing and a North/South station-keeping maneuver — the first few hours of Full Disk Visible (0.63 µm) images are shown above. The SSEC Satellite Data Services group was able to position a spare rooftop antenna to receive the GOES-14 data during this test.

A closer look at the southwestern portion of Hudson Bay (below) revealed a large and anomalously-late area of First-year ice off the coast of Ontario.

GOES-14 Visible (0.63 µm) images [click to enlarge]

In addition to the Imager, the GOES-14 Sounder is also operating. Recall that the sounder provides 18 infrared spectral bands and one visible band (below). A combined image showing both the Sounder and Imager bands has been generated.

GOES-14 Sounder mult-spectral animation from August 1, 2019 [click to play animation]

GOES-14 Sounder imagery are being posted in near real-time during this annual test.

===== 01 August Update =====

GOES-14 Shortwave Infrared (3.9 µm) images [click to enlarge]

GOES-14 Shortwave Infrared (3.9 µm) images (above) revealed the warm thermal anomaly or “hot spot” (darker red to black pixels) resulting from a natural gas explosion and fire in central Kentucky on 01 August (blog post).

Posted in Fire detection, GOES sounder, GOES-14 | No Comments »

Middle/upper-level deformation zone over the East Pacific Ocean?

May 23rd, 2017 | Scott Bachmeier

GOES-15 Water Vapor (6.5 µm) images, with pilot reports of turbulence [click to play animation]

An interesting linear feature appeared over the East Pacific Ocean on GOES-15 (GOES-West) Water Vapor (6.5 µm) images (above) on 23 May 2017, which at first glance immediately nominated it for the “What the heck is this?” blog category. A contrail was ruled out, since it was not oriented along a common or busy flight route — so potential large-scale dynamic processes were briefly investigated. Since the linear feature was perpendicular to the busy California/Hawaii flight route, pilot reports of turbulence are plotted on the water vapor images; two reports of light turbulence at altitudes of 33,000-34,000 feet (at 0918 and 1109 UTC) appeared to be close enough to have possibly been related to the linear feature.

GOES-15 Water Vapor (6.5 µm) images, with contours of satellite wind derived Upper-Level Divergence [click to enlarge]

Satellite atmospheric motion vector (AMV) derived products such as Upper-Level Divergence (above) calculated at 3-hour intervals (source) revealed an area of divergence focused near the area of the linear satellite image feature — around 30º N, 140º W, at the center of the images — which reached its peak intensity at 12 UTC; this suggested that the feature may have formed along the axis of the sharp deformation zone between two upper-level lows over the East Pacific Ocean (mid/upper level winds | 200 hPa Vorticity product).

GOES-15 sounder Water Vapor (6.5 µm, top; 7.0 µm, middle; 7.5 µm, bottom) images [click to enlarge]

Unfortunately, this region was not within the view of Himawari-8 or GOES-16 (each of which provide 2-km resolution water vapor imagery at 3 atmospheric levels). However, the GOES-15 sounder instrument has 3 similar water vapor bands (above) — albeit at a more coarse 10-km spatial resolution at satellite sub-point — which showed the linear “deformation axis cloud signature” at all 3 levels of the atmosphere. The GOES-15 sounder water vapor weighting functions for a “typical” US Standard Atmosphere are shown below.

GOES-15 sounder Water Vapor band weighting functions [click to enlarge]

Posted in Aviation, GOES sounder, GOES-15, Satellite winds, What the heck is this? | No Comments »

GOES-16 water vapor imagery: wave structures within a dry slot

March 8th, 2017 | Scott Bachmeier

GOES-16 Water Vapor images: 6.2 µm (top), 6.9 µm (middle) and 7.4 µm (bottom) [click to play animation]

** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

(Hat tip to T.J. Turnage, NWS Grand Rapids, for alerting us to this case): A variety of mesoscale wave structures were seen in NOAA GOES-16 Lower-Tropospheric Water Vapor (7.3 µm) and Middle-Tropospheric Water Vapor 6.9 µm images (above; also available as an MP4 animation) within a dry slot along the southern periphery of a trough associated with a large and intense mid-latitude cyclone centered over Hudson Bay, Canada on 08 March 2017. Beneath this dry slot, wind gusts exceeded 60 mph across southern portions of Minnesota, Wisconsin and Lower Michigan as momentum aloft was mixed downward to the surface.

Using the GOES-13 (GOES-East) Sounder water vapor bands as a proxy for the three ABI water vapor bands, weighting functions calculated using 12 UTC rawinsonde data from Chanhassen, Minnesota (below) showed a dramatic downward shift in the weighting function curves (compared to a US Standard Atmosphere) — this meant that the 3 water vapor bands were sensing radiation from layers much closer to the surface on 08 March (where the strong winds could interact with terrain and cause standing waves to form). It is interesting to note that the outline of the southern part of Lake Michigan could be seen on GOES-16 Lower-Tropospheric Water Vapor (7.3 µm) imagery (animated GIF | MP4 animation) — the signal of the thermal contrast between the lake water (MODIS SST values in the upper 30s to low 40s F) and the adjacent land surfaces (MODIS LST values in the middle 50s to low 60s F) was “bleeding up” through what little water vapor was present aloft.

GOES-13 Sounder water vapor weighting functions: 12 UTC Chanhassen, Minnesota sounding vs US Standard Atmosphere [click to enlarge]

A comparison of GOES-16 Visible (0.64 µm) and Middle/Lower-Level Water Vapor images (below; also available as an MP4 animation) showed that these water vapor wave structures were forming in cloud-free air — this is a signature of the potential for low-altitude turbulence.

GOES-16 images: 0.64 µm Visible (top), 6.9 µm Water Vapor (middle) and 7.4 µm Water Vapor (bottom) [click to play animation]

In fact, there were widespread pilot reports of moderate turbulence within the dry slot (below), with a few isolated reports of severe to even extreme turbulence in eastern Wisconsin and southern Lower Michigan.