Experimental MODIS RGB Color Composites of Hurricane Earl

One advantage of the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments aboard NASA’s Aqua and Terra satellites are their 36 spectral bands, covering a wider range of infrared, near-infrared, and visible portions of the electromagnetic spectrum.  With greater spectral coverage, specific channels have been investigated by the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) for use in color composites, where individual channels or channel differences are assigned to each of the red, green, and blue intensities of color that comprise the final color of a pixel in a visualized satellite image.  In the future, the GOES-R series of geostationary satellites will have a greater number of spectral channels, and although they will not replicate the full range of MODIS channels, they will have the ability to produce various RGB composites that are useful in identifying features or atmospheric properties that may be difficult to discern from a single channel image.  SPoRT is investigating RGB composite image processing techniques to determine the “best practices” for the use of MODIS data in this capacity, along with the data processing challenges with current AWIPS and future AWIPS II systems used by the National Weather Service.  In the images below (click for larger size), Hurricane Earl was observed by the MODIS instrument aboard the NASA Aqua satellite on August 30, 2010 around 1805 UTC, with various RGB color composites applied using current EUMETSAT techniques.  Future work will investigate how to produce these images in near real-time and their integration with NWS data processing systems.

MODIS True Color Composite

Hurricane Earl as viewed from the MODIS aboard Aqua, using three channels in the visible spectrum to produce a true color composite.

MODIS Air Mass

Application of the EUMETSAT "Air Mass" enhancement, which uses infrared brightness temperature channel differencing to enhance mid- to high-level clouds, moisture (greens) and relatively drier air (browns).

MODIS Convective Storms enhancement

Application of the "Daytime Convective Storms" enhancement, which uses a variety of infrared, near-infrared, and visible channel differences to highlight severe convection and the influx or outflux of water vapor.

MODIS Microphysics

Hurricane Earl as seen in the EUMETSAT "Daytime Microphysics" RGB composite, which uses visible and near-infrared reflectance, combined with an infrared channel, to separate cloud types such as convection, low clouds, and fog.

One thought on “Experimental MODIS RGB Color Composites of Hurricane Earl

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s