ABI Scan Mode Information and Channel Summary

On or about April 2, 2019, at 1600 UTC, the GOES-16 and GOES-17 Advanced Baseline Imagers will begin operating in a new 10-minute flex mode (mode 6). Ten-minute flex mode is very similar to the current flex mode (mode 3) with one exception: a full disk image is generated every 10 minutes instead of every 15 minutes. Contiguous U.S. (CONUS) for GOES-16/ Pacific U.S. (PACUS) for GOES-17 scans (3000 km by 50000 km) will still be provided every five minutes, in addition to two mesoscale domains (1000 km by 1000 km) every 60 seconds (or one domain every 30 seconds if scanning the same domain).

There are a number of advantages to 10-minute full disk images. It allows NOAA to match the full-disk scanning cadence of our international partners like the Japan Meteorological Agency (JMA), Korea Meteorological Administration (KMA), and the next generation of European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) geostationary satellites (starting in 2021). This allows nearly global advanced imager coverage every 10 minutes.

Ten-minute full disk imagery will also be critical to our National Weather Service Weather Forecast Offices, National Centers, and the Volcanic Ash Advisory Centers in monitoring hazardous weather conditions and providing additional information in observationally limited areas like over the oceans or in the mountains. The faster temporal cadence will also improve aviation safety. For example, GOES are paramount in monitoring volcanic activity and associated ash plumes. The improved temporal resolution will help monitor these rapidly changing events and help reduce the risk of an airplane encounter with an ash plume. In addition, GOES ABI data can also monitor regions of potential turbulence and since these features can be highly transient, the 10-minute full disk scanning ability will help with monitoring of this hazard.

The timelines, i.e. the number/type of scans in a 10-minute period, are slightly different between GOES-16 and GOES-17. This is intentional as more calibration and navigation scans are included in the GOES-17 mode 6 timeline to mitigate impacts of operating at higher temperatures.

GOES-16 (GOES East) will use timeline mode 6A and GOES-17 (GOES West) will use timeline mode 6M. Timelines for each satellite can be found at the NOAA Office of Satellite and Product Operations GOES Schedules and Scan Sectors webpage.

ABI: Scan Mode 6A: Timeline Definition

This depiction of the timeline is only accurate to 1/10 sec. resolution.
Tables scroll horizontally on small devices/screens.

ABI: Scan Mode 6M: Timeline Definition

This depiction of the timeline is only accurate to 1/10 sec. resolution.
Tables scroll horizontally on small devices/screens.

GOES-17 mode 6 improves the overall calibration of the PACUS and mesoscale scenes due to the optimization of mode 6 to reduce the magnitude of calibration fluctuations with more frequent calibration updates. The optimized version of the mode 6 timeline reduces periodic infrared calibration anomaly (PICA) impacts and decrease degradation during times of marginal impacts from increasing focal plane module (FPM) temperatures. There are PICA anomalies present in the data that can be seen as regular and repeating pulses in infrared brightness temperatures.

GOES-17 Cooling Timeline

For four periods each year, the NOAA Office of Satellite and Product Operations will implement a GOES-17 ABI cooling timeline. This operation mitigates the number of saturated images resulting from the loop heat pipe (LHP) temperature regulation anomaly. In this timeline, ABI generates a single full disk once per 15 minutes and generates one mesoscale domain sector (MDS) each minute for a six-hour (0600 – 1200 UTC) period each day. Alternating MDS domains are collected one time each per two-minute period. The contiguous United States (CONUS) domain is not scanned during the timeline, as those periods are used for cooling. This operations reduces the daily peak focal plane module temperature by ~4 Kelvin, which shortens the period of lost imagery by 30–90 minutes. For most channels and on most days, that means an additional 50–150 MDS images, 2–8 CONUS images, and 2–6 full disk images.

Please see the OSPO ABI Scan Mode 3 (G) Cooling Timeline webpage for cooling timeline dates.

ABI: Scan Mode 3 (G) Cooling Timeline

This depiction of the timeline is only accurate to 1/10 sec. resolution.
Tables scroll horizontally on small devices/screens.

ABI Technical Summary Chart