The new GPM Microwave Imager, or GMI, produced
unprecedented images of an extra-tropical cyclone in the Northwest
Pacific Ocean, east of Japan, on March 10, 2014.
The GMI measures the natural energy radiated by
different precipitation in the form of brightness temperatures.
The GMI produces a critical reference standard, which unifies all the member
satellites of the GPM Constellation. The instrument
has 13 channels, four more than onboard TRMM, and this
greater sensitivity allows GPM to measure a greater variety of
precipitation type and intensity. Each channel
has a frequency range that can detect a different type of precipitation.
The lower frequencies for moderate to heavy rain,
the middle frequencies for a mix of rain and snow,
and the higher frequencies for falling snow and ice.
Scientific algorithms then translate the
GMI's brightness temperature data into more meaningful products, such as
rain rates. Because GPM's coverage extends beyond
the tropics, measuring storms like these in the mid- and high-latitudes
will improve and expand the global view of precipitation.
[rain falling]