Satellite Displays

 For the warning decision making in RAC, satellite data is primarily used for environmental assessment and convective initiation, and satellite fundamentals is beyond the scope of this document. We will, however, describe a little about types of satellite products and displays in AWIPS.

The Satellite menu contains horizontal plots of different channels of satellite data and derived products for geostationary satellites such as the Geostationary Operational Environmental (GOES) East/West and Himawari, as well as polar orbiting satellites such as the Polar Operational Environmental Satellites (POES). GOES West is located over the western US, while GOES East is located over the eastern US. Since GOES are standard satellites for a large part of the US, all menus in the Satellite menu are GOES products unless otherwise labeled. There are single channel products like Visible and 3.9 micron (e.g. 3.9u), and there are also 4 panel linked displays, so you can zoom and step through loops in multiple panels. Routine GOES temporal frequency is 15 minutes while rapid-scan is about 5-10 minutes, and super-rapid scan is about 1 min. The satellite mosaic will display at a lower spatial resolution when zoomed out for performance reasons, and as you zoom in, higher resolution data will automatically display.

There are two GOES sections on the satellite menu: a combined GOES East/West mosaic at the top of the menu that mosaics based on a fixed time interval that is scale dependent (e.g. 30 min on North American scale and 15 min on CONUS and smaller scales) and a "NH/NA/US every image" composite in the bottom half of the menu that loads every image from all the sectors in the mosaic. The top menu is more continuous in space but lower resolution in time, while the bottom menu is less continuous in space and higher resolution in time. Image loops loaded with every image (bottom half of menu) tend to flicker when components of the mosaic are missing or do not time match. 

The GOES-16 and GOES-17 menus are located in the top pulldown menu, and these are where the extensive multi-channel products exist for the GOES-R series of satellites.

The Japanese Himawari satellite domain is over the Pacific, and it contains more channels than the GOES East/West satellites, similar to GOES-R. The Himawari products are located in their own menu.

POES provides higher spatial-resolution products over smaller areas as it circles the globe many times per day. POES products have their own section which also contains numerous derived products featuring unique satellite channels/combinations and derived winds and other environmental parameters. You can even launch vertical soundings for POES data by loading the S-NPP and NOAA-20 Products->NUCAPS Sounding Availability menu and clicking on the dots on the display.

One of the more advanced severe weather satellite-related products is the "Prob Severe" product available from the NOAA/CIMSS Convective Prob menu at the bottom of the satellite menu. The Prob Severe product uses GOES satellite data, MRMS radar data, Rapid Refresh model data, and lightning data to identify areas of severe weather probability. RAC will focus more on developing proficiency in base-data analysis, and sophisticated algorithms such as Prob Severe are beyond the scope of the course due to the complexity of assessing the quality of the guidance.

There are two AWIPS satellite display characteristics that are unique and worth mentioning: the satellite daylight transition and the gamma adjustment. If you load visible satellite data paired with another satellite product, you can use the right click on the the plus (+) sign between the paired products in the product legend to enable the daylight transition and automatically fade from visible to non-visible channels at sunrise and sunset (or set an offset around sunset/sunrise to start the transition). See the Satellite Daylight Transition VLab reference page for more information.

With GOES-16 and beyond, you can load an RGB composite product and be able to adjust the gamma settings of each channel to bring out certain features. Alternatively, you can combine up to 3 satellite channels as red (R), green (G), and blue (B) values yourself and adjust the gamma settings of the combined channels to create new satellite displays. You can accomplish this using the localization perspective with a provided template file on the Gamma Adjustment VLab reference page.

 loop
(GOES-16 false color composite bundle leveraging the gamma adjustment infrastructure)