Dust RGB Imagery GOES Beyond Visible

The Dust RGB imagery product was originally developed by EUMETSAT for the MeteoSat Second Generation (MSG) SEVIRI imager and later applied to the JMA Himawari-8 (H8) imager (same as GOES-16). Now the same capabilities are seen with the GOES-16 Advanced Baseline Imager (ABI).  NASA/SPoRT has transitioned this product to operational users since 2011 as part of the NOAA Satellite Proving Ground efforts to prepare users for this new geostationary era in the U.S.  SPoRT has co-authored an NWA/JOM article about the impacts this Dust RGB Imagery has already had in operation procedures via use with MODIS and VIIRS instruments. The value of the Dust RGB is the ability the user has to analyze dust plumes when single channel imagery, such as visible channels, do not adequately depict the dust feature.  In addition, true color imagery will often “miss” seeing dust because the underlying surface has a similar color to the dust itself.  And lastly, the Dust RGB allows one to continue monitoring the dust event in both day and night scenes.  Below is an example from a blowing dust event today (March 6, 2017) in the Nebraska and Colorado areas.  Note in the comparison image that the dust (shown in magenta coloring) is readily apparent compared to using single channel visible (0.64 micron, channel 2) imagery alone.  Further below are loops of the imagery for comparison.  Also, note that dry vs. moist air is apparent and another utility of the imagery will be the analysis of drylines in the deep south of the U.S.

DustRGBcompare_Vis_20170306

NOAA’s GOES-16 satellite has not been declared operational and its data are preliminary and undergoing testing. Users receiving these data through any dissemination means  (including, but not limited to, PDA and GRB) assume all risk related to their use of GOES-16 data and NOAA disclaims any and all warranties, whether express or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose.

While the Dust RGB Imagery is not intuitive at first, one only has to look at the area over southern Nebraska  (see below) to see a streak of magenta that represents a dust plume.  The Dust RGB uses several infrared-based channels to differentiate various cloud characteristics and dust.  Particularly useful is the difference between channels 15 and 13 (i.e. 12.3 – 10.4 micron difference) that takes advantage of the low absorption by dust in channel 15, which results in a relatively large positive differnce.  This is the red component of the Dust RGB and it causes dust to have a greater amount of red compared to other cloud features.  The magenta color in the RGB results because the dust is relatively warm and the blue component of the RGB is the 10.4 micron channel which is sensitive to the thermal properties of the object.  In addition to the streak across Nebraska, the region of eastern Colorado also has a dust signature in the RGB.  At the time of this imagery, there were 40 kt wind gust and haze reported over this area, but the dewpoint temperatures were below zero degrees Celcius. While no dust was reported in the METAR observations at the time, it’s likely some type of blowing dust was causing the “haze” and some reduced visibility reports.

GOES16DustRGBExample

GOES16-VIS-Example

NOAA’s GOES-16 satellite has not been declared operational and its data are preliminary and undergoing testing. Users receiving these data through any dissemination means  (including, but not limited to, PDA and GRB) assume all risk related to their use of GOES-16 data and NOAA disclaims any and all warranties, whether express or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose.

Resources for the Dust RGB:

NASA/SPoRT Quick Guide: Dust RGB

SPoRT Application Library: Dust RGB Identifies Aviation Ceiling Hazard at KFMN (micro-lesson)

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