After a series of six delays, a rocket carrying a pair of satellites designed to give scientists their first three-dimensional view of clouds blasted off early Friday, kicking off a study of how clouds affect weather and climate.
CloudSat and CALIPSO were then successfully deployed into a pole-to-pole orbit — joining the "A-Train" constellation, a group of environmental spacecraft already surveying the atmosphere. The "A-Train" includes NASA's Aqua and Aura satellites as well as the French Parasol satellite.
CloudSat has powerful radar instruments to peer deep into the structure of clouds and map their water content. Although they contain only about 1 percent of Earth's water, clouds play a crucial role in the planet's weather, scientists working on the mission said.
"CloudSat will answer basic questions about how rain and snow are produced by clouds, how rain and snow are distributed worldwide, and how clouds affect the earth's climate," principal investigator Graeme Stephens of Colorado State University said.
Using instruments 1,000 times more powerful than common meteorology radar, CloudSat will render three-dimensional maps of clouds that identify the location and form of water molecules.
Complementary and virtually simultaneous studies by sister probe CALIPSO will pinpoint aerosol particles and track how they interact with clouds and move through the atmosphere. CALIPSO is an acronym for Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations.
Aerosols are formed by natural phenomena such as forest fires, as well as human activity such as driving cars. Aerosols are considered a key factor in understanding climate change.
Computer models predict that average surface temperatures on Earth could increase by 2 to 6 degrees Fahrenheit (1 to 3.5 degrees Celsius) or even more over the next 100 years. Some of the uncertainty in the prediction stems from the role clouds play in moderating heat. Aerosols in the clouds can either cool the planet by reflecting solar energy back into space, or increase temperatures by trapping heat in the atmosphere.
"We need to understand the aerosol effect on climate because it counteracts the effects of greenhouse gases," said CALIPSO principal investigator David Winker of NASA's Langley Research Center in Hampton, Va.
The successful launch came after a week of delays blamed on a communication failure, logistical snags, bad weather and a fleeting concern about a temperature sensor. The satellites were supposed to be launched last year, but technical difficulties and a strike by Boeing workers kept them grounded until this month.
This report includes information from The Associated Press, Reuters and MSNBC.com.