Can Geostationary Imagers See Noctilucent Clouds?

June 20th, 2022 |

Q: Can geostationary imagers see the very thin, very high Noctilucent Clouds? A: Yes and no, depending on the satellite, how data are processed, time of the year, time of the day and spectral band. Thanks to Simon Proud for this tweet using JMA‘s Advanced Himawari Imager (AHI):

Note the very thin line near the top of the images on June 20, 2022. These images are derived from Japan’s AHI. A animated gif version.
A similar loop as above, but more zoomed in. From June 20, 2022. These images are derived from Japan’s AHI. An animated gif version.
A “spectral” loop of AHI’s three visible bands at 15 UTC on June 20, 2022. A animated gif version.

Since NOAA’s ABI is a similar instrument to AHI it seems likely that ABI can also observe noctilucent clouds at times. Noctilucent clouds are possibly only observable in visible bands when they are off the earth’s edge, with space as a background, and when illuminated from certain angles. However, due to ground system processing in the generation of the ABI radiance files, most users cannot see data that the ABI scans off the Earth’s edge in space. Special processing of ABI data does allow to show off Earth pixels, such as in these examples with the moon and the Webb Space Telescope plume in space. Recall that the AHI Full Disk is made up of 23 swaths (as opposed to 22 for the ABI), so it scans a bit more space both north and south of the Earth.

An animation including the AHI 3.9 micrometer band shows the relationship between the Earth’s edge and the apparent cloud location. (A animated gif version.) Consider also the large apparent displacement of these high altitude (“shining at night”) clouds due to parallax.

Also see this image:

GOES-2 Launch Anniversary; GOES Timelines

June 16th, 2022 |

With the help of NASA, private industry and others, NOAA’s GOES-2 (as GOES-B) was launched on June 16, 1977. Similar to SMS-1/2 and GOES-1/3, there were 2 spectral bands: one visible and one longwave infrared.

GOES-2 Visible (left) and Infrared (right) spectral bands from June 16, 1978 over the Eastern portion of the U.S.

A still image with a map overlay is also available to provide geo-referencing for the images in the above animation. Or a similar loop is also available with the map overlay The images in the loop (mp4 | animated gif) were taken just one year after GOES-B was launched.

A timeline of the GOES, from GOES-1 to GOES-U. Figure credit: GOES-R Program Office. (Click to show larger image.)
A timeline of the U.S. geo imaging, from ATS/SMS to GOES-U. Figure credit: GOES-R Program Office. (Click to show larger image.)

The timelines show the periods when the satellites were operational. Yet, there were other times when they might have been operating. For example, when an on-orbit spacecraft comes out of storage once a year, often in August, for a routine check-out of several weeks. Another example was GOES-14, as it provided over 5 months of 1 min data (SRSOR) data to better prepare for the meso-scale sectors on the ABI. These campaigns were in 2012, 2013, 2014, 2015 and 2016. Some of these times were:

Start DateEnd Date
16-Aug-201231-Oct-2012
13-Aug-201328-Aug-2013
08-May-201425-May-2014
14-Aug-201428-Aug-2014
18-May-201511-Jun-2015
10-Aug-201528-Aug-2015
01-Feb-201625-Feb-2016
18-Apr-201615-May-2016
09-Aug-201629-Aug-2016
01-Aug-201711-Aug-2017
08-Aug-201817-Aug-2018
31-Jul-201913-Aug-2019
11-Aug-202021-Aug-2020
11-Aug-202119-Aug-2021
GOES-14 times (as start/end pairs) of being operated, though not operational. All dates are approximate.

In addition, GOES-15 was operated several times to supplement GOES-17 operations:

Start DateEnd Date
20-May-201809-March-2020
04-Aug-202004-Sep-2020
04-Feb-202119-Feb-2021
02-Aug-202105-Nov-2021
17-Feb-202218-April-2022
GOES-15 times (as start/end pairs) of being operated, though not operational. All dates are approximate.

The second timeline above includes not only the U.S. GOES imagers, but also their precursors: ATS-1, 3 (including the Spin Scan Cloud Cameras) and 6 (with the 2-channel GVHRR; including an infrared band) and SMS-1/2. The GOES-R Program Office also has a more simple GOES timeline.

UW/SSEC has an interactive timeline (opens in new tab) that covers more satellites. The SSEC library (Schwerdtfeger) also has more information on the Spin-Scan Cloud Cameras on ATS-1/3.

Snapshot of the UW/SSEC timeline, the orange line relates to the geostationary orbit. (Click to better show image.)
A GOES-2 Full Disk image from June 16, 1978. The visible band is shown, along with cold IR values. (Click to show larger image.)

The above image shows a color-coded transparency for cold clouds over the gray-scale visible image.

After GOES-U, NOAA is planning on the next generation U.S. geostationary imager as part of the Geostationary Extended Observations (GeoXO) program.

H/T

Thanks to the many who made the GOES (and the precursors) possible. McIDAS-X software was used in generating these satellite images. The data (and many dates) was accessed by the UW/SSEC Data Services. More about GOES-16 and GOES-17 and GOES-18 (preliminary, non-operational).

GOES-18 (Prelim/Non-Op) ABI 16-panels

June 8th, 2022 |

Even though GOES-18 is currently preliminary, non-operational, ABI 16-panels are being generated for both the Full Disk and “PACUS” (Pacific US) sectors. GOES-18 arrived near the GOES-West position to continue post-launch checkout on June 6, 2022 and the ABI was started scanning early (UTC time) on June 7. To access the images, select “GOES-18”, choose a Region (sector), and “16Panel” for the parameter. (GOES-16 and GOES-17 are available as well). The sector choices are called “CONUS” and “Full Disk” but for GOES in the West location the CONUS sector is often referred to as “PACUS” since it includes the NE Pacific Ocean and western part of the contiguous United States (plus Hawaii).

NOAA and NASA recently released the first ABI (Advanced Baseline Imager) imagery from GOES-18 (including this 2-min video). GOES-T was launched on March 1st and both GOES-16 and GOES-17 monitored the rocket signature. GOES-18 is the third in the GOES-R series and is currently located at approximately 136.8W, having been relocated from its initial geostationary checkout position at 89.5W. GOES-18 is slated to become NOAA’s operational GOES-West in early 2023 after going through many tests. Before that, the ABI on GOES-18 will become the operational imager during two GOES-17 Loop Heat Pipe times. Also see this satellite liaison post. Also see these other GOES-18 related blog posts.

GOES-18 (preliminary, non-operational) “CONUS” sector 16 panel.

There are 2 visible, 4 near-infrared and 10 infrared bands. A still image of all 16 bands for the “PACUS.”

GOES-18 (preliminary, non-operational) “Full Disk” sector 16 panel.

A still image of all 16 bands for the Full Disk.

H/T

Thanks to the many (thousands) who made the GOES-18 ABI possible. These GOES-18 ABI are early images (preliminary and non-operational, calibration improvements are possible. McIDAS-X software was used in generating these images. More about GOES-16 and GOES-17.

GOES-18 ABI Imagery Comparisons

May 13th, 2022 |

NOAA and NASA recently released the first ABI (Advanced Baseline Imager) imagery from GOES-18. GOES-T was launched on March 1, 2022. (see the GOES-T launch as GOES-16 and GOES-17 monitored the rocket signature). GOES-18 is the third (of four) in the GOES-R series and is currently located above the equator at approximately 90W. GOES-18 is slated to become NOAA’s operational GOES-West in early 2023 after going through extensive post-launch testing. Also, see this CIMSS Satellite Blog post or this Satellite Liaison Blog post.

GOES-18 Compared to other GOES

Remapped GOES-16, -17 and -18 ABI data from 18 UTC on May 6, 2022.

While it is still very early in the post-launch test period, good qualitative agreement has been shown to other GOES imagers, except when comparing to GOES-17 during times it is affected by the Loop Heat Pipe issue. Of course, due to parallax and other reasons, there are expected to be differences, especially at larger view angles. The above loop as a mp4 and animated gif. Or versions that toggle between GOES-18 and GOES-16 only (mp4 and animated gif).

GOES-18 and GOES-16 Band 10 images at 14 UTC on May 6, 2022.

GOES-18 images of the western United States collected by the Advanced Baseline Imager (ABI) on May 6, 2022. The GOES-18 ABI band 10 (7.3 micrometers) image is on the left, while the GOES-16 image is on the right. Note that the data are in the same projection. Warmer brightness temperatures are mapped to warmer colors. Time animations (from 12 to 22 UTC) of these 2 panels are available for each band: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and 16 (mp4).

Remapped GOES-17 and GOES-18 Band 10 images at 18 UTC on May 6, 2022.

GOES-18 image of the United States collected by the ABI on May 6, 2022. The GOES-18 ABI band 10 (7.3 micrometers) image is on the right, while the GOES-17 image is on the left. This 2-panel “water vapor” image shows overall agreement, with less noise shown on GOES-18 compared with GOES-17. These GOES-18 ABI are early images, calibration improvements are possible. Time animations (from 12 to 22 UTC) of these 2 panels are available for each band: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and 16 (mp4).

3-panel Comparisons (GOES-17, -18, -16)

These 3.9 mircometer band comparisons are thanks to Scott Bachmeier. Direct links for the CA and NM cases of a CIMSS Satellite Blog.

ABI Instrument Response Functions

“Flight Model 3” or GOES-18 ABI Spectral Response Functions for the 10 infrared bands.

The ABI has 16 spectral bands, 2 in the visible, 4 in the near-infrared (or “near-visible”) and 10 in the infrared part of the electromagnetic spectrum. The instrument response functions can be found both on CIMSS and Calibration Working Group sites.

H/T

Thanks to the many (thousands) who made the GOES-18 ABI possible. These are GOES-18 ABI are early images (preliminary and non-operational, future calibration improvements are possible. geo2grid and McIDAS-X software was used in generating these images. More about GOES-16 and GOES-17.