GOES-17 ABI Temperature Data Quality Flags (TDQF) thresholds updated

October 2nd, 2019 |

Top: Thumbnails of GOES-17 and GOES-16 ABI Band 12 (9.6 µm) on August 1, 2019. Bottom: Time series of GOES-17 minus GOES-16 brightness temperature for a region located between the two satellites. Also plotted is the GOES-17 Focal Plane Temperature. The reduced duration of the GOES-17 data to be flagged is highlighted. [click to enlarge]

As of 19:45 UTC on August 8, 2019, the new Look-Up-Table (LUT) went into operations for use in the GOES-17 ABI Temperature Data Quality Flags (TDQF). These hotter thresholds are possible due to the recent implementation of the Predictive Calibration algorithm.  Note that the image also includes the percent good (and conditionally usable) values (flagged 0 or 1) for both GOES-16 and GOES-17 ABI. Recall there are 5 Data Quality Flags for ABI data:

  • DQF:percent_good_pixel_qf = 1.f ;
  • DQF:percent_conditionally_usable_pixel_qf = 0.f ;
  • DQF:percent_out_of_range_pixel_qf = 0.f ;
  • DQF:percent_no_value_pixel_qf = 0.f ;
  • DQF:percent_focal_plane_temperature_threshold_exceeded_qf = 0.f

The last one, DQF:percent_focal_plane_temperature_threshold_exceeded_qf, reports what percentage of the images pixels are warmer than the threshold value. Note that the thresholds on both the increasing and decreasing temperatures are also reported in the meta-data.

Near realtime brightness temperature comparisons between GOES-16 and GOES-17, as well as historical comparisons for a region centered on the equator and half way between the two satellites.

From the NOAA Notification:

Product(s) or Data Impacted: GOES-17 ABI auxiliary field change

Date/Time of Initial Impact: August 8, 2019 1945 UTC

Details/Specifics of Change:

The GOES-17 ABI Temperature Data Quality Flags (TDQF) thresholds for the thermal bands have been updated to the values in the table below.  This update will make utilizing the TDQF more effective for flagging saturated data caused by the GOES-17 ABI cooling system anomaly. There will be no impacts to distribution caused by this update.

Table of updated Temperature Quality Data Flag thresholds [click to enlarge]

Table of updated Temperature Quality Data Flag thresholds [click to enlarge]

Update (10/02/2019)

On October 2, 2019, at 17:04 UTC, updates for a number of the ABI GOES-17 DQF thresholds were implemented in the operational system. NOAA Notification: https://www.ospo.noaa.gov/data/messages/2019/MSG2751954.html

Table of updated Temperature Quality Data Flag thresholds

Table of updated Temperature Quality Data Flag thresholds [click to enlarge]. The bold numbers are those values that were updated on October 2nd. 

GOES-16 ABI Derived Products such as Cloud-top Phase in AWIPS

August 14th, 2019 |
AWIPS

AWIPS image of the Contiguous US domain showing the ABI 3.9 µm (on the left portion of the image and the ABI 1.6 µm (on the right portion of the image). The readout of the Level 2 cloud-top phase is also displayed.

The above animation shows the ABI 3.9 µm band for regions of less solar illumination and the ABI 1.6 µm “snow/ice” band for regions more fully illuminated. Also shown is a readout of the GOES-16 cloud-type phase product for a point in eastern Texas. Note how the estimates range for this location from clear sky, liquid water, mixed phase and super-cooled droplets. This shows one example of how to use imagery in conjunction with derived products. These images where generated in AWIPS using a procedure.

Cloud-top phase can be found in RealEarth (search on ‘phase’), GEOCAT (direct link to cloud-top type), and the GOES-R cloud page. An archive of netCDF are held in NOAA’s CLASS.

There are many “Level 2” or derived products generated from the ABI radiances. These include, but are not limited to: cloud proprieties, atmospheric motion, fire, stability, sea and land surface temperatures. More information on these products can be found on the Algorithm Working Group web page, product quality web page or these links.

AWIPS image

AWIPS image of the Contiguous US domain showing the ABI 3.9 µm (on the left portion of the image and the ABI 1.6 µm (on the right portion of the image). The readout of the Level 2 cloud-top phase is also displayed.