GOES-14 Full Disk 6.5 µm water vapor images

On Day 2 (01 December 2009) of the GOES-14 NOAA Science Test, the satellite was placed into a continuous “Full Disk” scan mode, providing images of the entire hemisphere at 30 minute intervals — full disk images of the GOES-14 6.5 µm “water vapor channel” are shown above. While the current GOES operational scan schedule provides 1 full disk image every 3 hours, the ABI instrument on the upcoming GOES-R satellite will have the ability to provide full disk images every 5 minutes!

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GOES-11, GOES-14, and GOES-12 3.9 µm shortwave IR images

A comparison of GOES-11 (GOES West), GOES-14, and GOES-12 (GOES East) 3.9 µm shortwave IR images (above) indicated that there were a number of fires burning across parts of southern British Columbia, Canada on 01 December 2009, as confirmed by the NOAA Hazard Mapping System. The 3 sets of images are displayed in the native projection of their respective satellites. The fire “hotspots” showed up as warmer (darker black enhancement) pixels.

The plot below shows that the warmest 3.9 µm IR brightness temperature on the GOES-14 imagery was 325.8º K at 22:15 UTC, compared to 317.7º K on GOES-11 at 20:15 and 304.9º K on GOES-12 at 19:45 UTC. This difference in maximum fire pixel brightness temperature and time was due to such factors as different satellite viewing angles (compounded by the steep slopes of the mountainous terrain) and possible brief obscuration by clouds and/or smoke.

Plot of maximum fire pixel IR temperatures from GOES-11, GOES-12, and GOES-14

AWIPS images of the MODIS visible and 3.7 µm shortwave IR channel data from 19:46 UTC are shown below; again, a number of darker black fire hot spots can be seen on the shortwave IR image across parts of southern British Columbia (as well as to the east across southern Alberta). The visible image revealed that there was a great deal of snowpack in the mountains of the region — however, there were also a few patches of supercooled water droplet cloud and/or fog in the higher terrain, which showed up as darker gray features on the shortwave IR image (due to solar reflection off the tops of the supercooled clouds/fog).

MODIS visible and 3.7 µm shortwave IR channel images

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GOES-11, GOES-12, and GOES-14 visible images

GOES-14 (launched on 27 June 2009) began its NOAA Science Test on 30 November 2009 — and McIDAS images of the GOES-11, GOES-12, and GOES-14 visible channel data (above) showed an area of melting snow cover across the Texas / New Mexico border region. This area (southwest of Amarillo, Texas) had received 1-3 inches of new snowfall on 29 November, which then rapidly melted under full sun on the following day. Note the improvement in Image Navigation and Registration (INR) on the GOES-14 images — there is much less image-to-image wobble compared to the GOES-11 (GOES West) and GOES-12 (GOES East) images. The 3 sets of images are displayed in the native projection of their respective satellites.

Better INR performance is critical to improving the accuracy of such satellite-derived products as the 1-hourly MADIS atmospheric motion vectors, seen overlaid on an AWIPS image of the MODIS 11.0 µm IR channel data (below).

MODIS IR image with MADIS 1-hour atmospheric motion vectors

A comparison of the MODIS visible and 2.1 µm near-IR “snow/ice channel” images (below) confirms that this feature was indeed snow — snow and ice are strong absorbers at the 2.1 µm wavelength, and appear as very dark features on the snow/ice image.

MODIS visible and near-IR "snow/ice" channel images

Note how the MODIS Land Surface Temperature (LST) product (below) was showing LST values in the upper 30s to low 40s F (green colors) over the snow-covered areas, in contrast to much warmer LST values in the middle 50s to low 60s F (yellow colors) over the surrounding bare ground. The surface air temperatures were also being held down into the upper 30s to low 40s F over the melting snow cover.

MODIS Land Surface Temperature product

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Shortly after midnight (EST) on December 1st, GOES-10 was decomissioned and boosted to a disposal orbit (approximately 300 km above the operational orbit). It was shut off because it lacks fuel for the required maneuvers to keep it on station.

GOES-K was launched 25 April 1997, with a life expectancy of five years. A solar array problem shortly after launch in May of 1997 was nearly fatal to the spacecraft; however, a yaw-flip maneuver (that is, flying the spacecraft upside-down) proved successful and GOES-10 has successfully served data nearly continuously since then. The first visible image from GOES is here. Early examples of Sounder and Imager are also available. For more examples of GOES-10 imagery, click here. GOES-10 served as GOES-West from 27 July 1998 (replacing GOES-9) until 21 July 2006 (when it was replaced by GOES-11). GOES-10 then moved from 135 West Longitude to 60 W Longitude, arriving on station in December 2006 to provide near-continuous data over South America (More information on GOES-10 is available here).

As a Geostationary satellite focused on South America, GOES-10 provided valuable information about the Air France Flight Crash over the Atlantic Ocean, volcanic eruptions over South America. In addition, as it moved from 135 W Longitude to 60 W Longitude, it was in Super Rapid-Scan Operation mode — that is, imagery was collected every minute over limited regions — to give insight into various meteorological phenomena. (For more links to GOES-10 imagery, click the GOES-10 category, or click here).

With the termination of GOES-10 operations, routine satellite observation of South America will fall to GOES-12, the operational GOES-East satellite. However, the operational demands on GOES-East preclude the high temporal observations that GOES-10 provided. For example, much of South America now has routine 15-minute coverage; GOES-East will provide only half-hourly coverage. This image loop shows the motion of a smoke plume — at 15-minute intervals — near the Tocantins River just south to the Amazon Delta. A similar loop from GOES-East is here. Reduced temporal resolution introduces greater error to both cloud-tracked features (derived winds) and fires detected.

Similar views from different vantage points can be important. Consider, for example, the twin views of northeast Brazil in the 4-micron band from GOES-10 and GOES-12.

Both platforms observe the fires in the Amazon River delta in the upper left part of the images. Note, however, that only GOES-East shows a very warm Lake behind Sobradinho Dam on the Sao Francisco River. Indeed, the 3.9-micron sensor has saturated on GOES-East (over the Equator at 75 W), but GOES-10 (over the Equator at 60 W) shows very little signature. This is an excellent example of Sun Glint in the 3.9 micron channel. Solar 3.9-micron radiation reflected from the lake is saturating the instrument on GOES-East. GOES-10, farther east, can look at the same region and not see the Sun Glint.

In contrast to GOES-East and GOES-West data, data from GOES-10 have been remapped before distribution since it arrived at 60 West back in late 2006. The remapping is necessary because the satellite inclination was large; indeed, it was more than 4 degrees on 25 November 2009.

Update: The Final Imager images from GOES-10: 0.65 microns; 3.9 microns; 6.8 microns; 10.7 microns; 12.0 microns; Infrared Channels in a loop.

Current plans are for GOES-13 to replace GOES-12 as GOES-East in April of 2010. Subsequently, GOES-12 will move to 60 W and resume GOES-10’s duties.

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