US-Japan joint rain radar mission to end next year

After 17 years of groundbreaking 3-D images of rain and storms, the joint NASA and Japan Aerospace Exploration Agency Tropical Rainfall Measuring Mission (TRMM) will come to an end next year, the US space agency said in a statement.

NASA predicts that science operations will cease in or around April 2015.

Orbiting at an angle to the equator that covers 35 degrees north to 35 degrees south of the equator, TRMM carries five instruments that collectively measure the intensity of rainfall, characteristics of the water vapour and clouds, and lightning associated with the rain events.

One of the instruments, the Precipitation Radar, built by Japan Aerospace Exploration Agency (JAXA), is the first precipitation radar flown in space.

"TRMM has been the world's foremost satellite for the study of precipitation and climate processes in the tropics, and an invaluable resource for tropical cyclone research and operations," said Scott Braun, TRMM project scientist at NASA's Goddard Space Flight Centre.

Launched in 1997 as a three-year mission, TRMM's extended mission life has provided a boon to the scientific understanding of precipitation and its role in broad weather patterns and climate.

Recent pressure readings from the fuel tank indicated that TRMM was near the end of its fuel supply.

The joint operations will come to an end around April next year, based on the most recent analysis by mission operations at NASA's Goddard Space Flight Center, Greenbelt, Maryland, the statement said.

TRMM has allowed scientists to better understand how rain varies daily, seasonally and annually; how El NiAo affects global rain patterns; how regional rain events like the Indian monsoon vary throughout the season.

It has also allowed to understand how humans have affected local precipitation through the effects of urban heat islands, deforestation and pollution, the statement said.

NASA has launched five new Earth science missions in 2014 to expand our understanding of Earth's changing climate and environment.