Of the six instruments on GOES-East satellite for observing the Earth and Sun, it is the "Advanced Baseline Imager" (ABI) instrument that provides visible and infrared views the Earth. The ABI produces images at 16 different wavelengths, called bands and/or channels.
The individual channels are as follows:
There are two visible bands, blue and red, named relative to their location on the visible portion of the electromagnetic spectrum.
While in their natural state, these images would appear in blue and red hues respectively, but colors have been desaturated to appear in grayscale. Since these are "visible" channels, the images will appear black at night.
Channel 1: The "Blue" band
Located in the blue portion of the visible spectrum, it provides nearly continuous daytime observations of dust, haze, smoke, and clouds. It also includes measurements of "aerosol optical depths" that help air quality monitoring and tracking. Measurements in the blue band may provide estimates of visibility as well.
There is no "green" channel. That is important as all three colors - red, green and blue - are needed to product a true color image. The information made available by the next channel below, the "Veggie" band, is used to simulate the "green" color needed to produce a "color" image.
Channel 3: The "Veggie" band
Although this is a "near-infrared" band (not visible to the eye), vegetation is readily seen at this wavelength, giving it the nickname "veggie" band. It is useful in assessing land characteristics when determining fire and flood potential. For example, forest fire damage will appear darker than nearby unaffected areas, which helps pinpoint locations where significant rainfall may lead to flooding and mudslides.
Water is very absorptive of this wavelength, which makes it appear dark in the image, resulting in a high contrast between land and water. Channel 3 is also used to simulate a "green" band needed to produce a red-green-blue (RBG) color image.
Water Vapor Bands
The satellites do not directly detect moisture but actually detect temperature. Water vapor (water in a gaseous state) absorbs radiation at these particular frequencies. When much radiation has been absorbed by water vapor the satellite does not sense much radiation and therefore records a low temperature.
The satellite interprets a low temperature as high water vapor content. When much radiation is received by the satellite, it senses a high temperature and consequently a low amount of water vapor.
As a result, the depth at which the satellite peers into the atmosphere will vary with amount of moisture over any particular point from day to day.
Channel 8: The "Upper-level" Water Vapor band
The primary use for this band is upper level feature detection such as jet streams, troughs/ridges, and signs of potential turbulence.
Channel 9: The "Mid-level" Water Vapor band
The middle water vapor channel. Unless higher-level clouds obscure the view, this band can view as low as 500 mb level (about 18,000 feet/5,500 meters). It is used for mid and upper-level water vapor tracking, jet stream identification, hurricane track forecasting, mid-latitude storm forecasting, severe weather analysis, and mid-level moisture estimation.
The following channels in the infrared range will appear to look similar. There are subtle differences between the channels but their value is when are compared to each other.
Channel 11: "Cloud-top" phase
Clouds can consist of the following phases; liquid water, super-cooled water (droplets remain in liquid form although the temperature is BELOW freezing) or frozen. This band is similar to the "traditional" infrared band (channel 14, below) but with the added benefit of helping to determine cloud phase. It is used in combination with channels 14 and 15 to help derive cloud phases during both day and night. This band is essential for generating many products.