The Rain Falls Mainly in the...?
Tropical rainfall makes up more than two-thirds of the global rainfall in a given year. This is rain that falls between the latitudes of the Tropic of Cancer and the Tropic of Capricorn. Its role on a global scale is to distribute and circulate heat throughout the atmosphere. Tropical rainfall is anything but static. Its variability is crucial to understanding and predicting global changes such as climate.
News story originally written on September 29, 1997
The Tropical Rainfall Measuring Mission (TRMM) is the first Earth science satellite dedicated to studying the properties of tropical and subtropical rainfall. The mission is a combined effort between NASA's Mission to Planet Earth program and the National Space Development Agency of Japan.
The satellite was supposed to be launched October 31, 1997 from a Japanese launch site. It will still be launched from Japan, but the launch date has been delayed to November 18, 1997. The TRMM satellite is to be launched with another satellite. Engineers just found problems with TRMM's companion satellite and so they are taking the extra two weeks to fix the mechanical problems.
Current information about tropical rainfall is limited, especially over the oceans. The TRMM's state-of-the-art instruments will provide accurate measurements of the distribution and variability of tropical rain and lightning. These new measurements will help to clarify the effect tropical rainfall has on the Earth's climate as well as on biological and ecological Earth processes. Scientists are especially hoping that TRMM's measurements will shed light on the El Nino condition that seems to be brewing.