Table describing some of the most widely used RGB products, with a sample image for the dust RGB


Based on infrared channel data, this RGB is designed to monitor the evolution of dust storms during both day and night. This is challenging because the appearance of dust changes radically from day to night. Note that the dust RGB is nearly identical to the ash RGB but has slightly different tuning (temperature difference thresholds and enhancement of individual red, green, and blue inputs are slightly modified).

The current MODIS, MSG SEVIRI, and Suomi NPP imagers have the necessary channels to make this product. Future JPSS VIIRS, FY-3 MERSI-2, GOES-R ABI, Himawari AHI, FY-4 AGRI, and MTG FCI instruments will also have the needed channels for producing a dust RGB.

Coverage: Both day and nighttime


  • Polar-orbiting satellites:
    • MODIS:
      Red: 12.0 minus 11.0 µm IR BT difference
      Green: 11.0 minus 8.6 µm IR BT difference
      Blue: 11.0 µm IR
    • Suomi NPP and future JPSS VIIRS:
      Red: 12.0 minus 10.8 µm IR BT difference
      Green: 10.8 minus 8.6 µm IR BT difference
      Blue: 10.8 µm IR
    • FY-3 MERSI-2:
      Red: 12.0 minus 10.8 µm IR BT difference
      Green: 10.8 minus 8.55 µm IR BT difference
      Blue: 10.8 µm IR
  • Geostationary satellites:
    • MSG SEVIRI and future MTG FCI:
      Red: 12.0 minus 10.8 µm IR BT difference
      Green: 10.8 minus 8.7 µm IR BT difference
      Blue: 10.8 µm IR
    • Future GOES-R ABI:
      Red: 12.3 minus 10.35 or 11.2 µm IR BT difference
      Green: 10.35 or 11.2 minus 8.5 µm IR BT difference
      Blue: 10.35 or 11.2 µm IR
    • Future Himawari AHI:
      Red: 12.35 minus 10.45 or 11.2 µm IR BT difference
      Green: 10.45 or 11.2 minus 8.60 µm IR BT difference
      Blue: 10.45 or 11.2 µm IR
    • Future FY-4 AGRI:
      Red: 12.0 minus 10.7 µm IR BT difference
      Green: 10.7 minus 8.5 µm IR BT difference
      Blue: 10.7 µm IR

Color scheme::

  • The color of dust varies, from red for very high-level dust (quite rare), to bright magenta for low-level dust during daytime, to dark magenta for low-level dust at night
  • Thick, high-level clouds are red
  • Thin, high-level clouds are dark blue or black, except in sandy areas where they may appear in shades of are green and yellow
  • Thick, middle-level clouds appear brown
  • Thin, middle-level clouds appear green
  • Low clouds appear pink when the atmosphere is warm and olive green when the atmosphere is cold
  • Moist low levels, particularly a moist boundary layer, appear in bluish shades
  • Land and water backgrounds appear in shades of green and blue


  • Can follow the evolution of dust plumes during both day and night
  • Can depict dust plumes over land and water surfaces


  • The lack of solar channels can impede the detection of dust plumes, especially over the ocean; however, high-level dust clouds are always easy to detect given the large thermal contrast between elevated dust and the underlying surface
  • It is almost always easier to detect low-level dust clouds during the day when there is a larger thermal contrast between the land and elevated dust; this thermal contrast is smaller at night, making it more difficult to detect low-level dust with satellite products at night

Live data links:

Additional information:


Lensky I. M. and D. Rosenfeld, 2008: Clouds-Aerosols-Precipitation Satellite Analysis Tool (CAPSAT). Atmos. Chem. Phys., 8, 6739-6753.

Example 1:

Dust RGB animation showing the evolution of a dust storm over several days over Saudi Arabia

Loop: This animation shows how dust (in brighter magenta) can be easy to detect, especially during daytime, and more difficult to detect at night. Higher clouds appear deep red or black but can also appear in shades of yellow and green over sandy areas. Notice the tremendous dust storm moving through Iraq and the Persian Gulf near the start of the loop.

MSG Dust RGB  03 Mar 2004 0112 UTC showing dust at night

Example 2: Notice how the dust RGB identifies dust at night, something that most dust enhancements fail to do. The keys for this product are the channel differences, which help identify dust regardless of the time of day.


MSG-1 Dust RGB 10-09, 09-07, 0925  June 2003, 1000 UTC

In this daytime dust RGB, notice how dust looks over water (below the black arrow) vs. land (beside the white arrows). Over which surface is dust easier to detect? (Choose the best answer.)

The correct answer is B.

Infrared RGBs will always show dust better over a heated land surface than over bodies of water, which tend to radiate at a similar temperature to the dust.