February 23, 2009

Orbiting Carbon Observatory Ready For Liftoff

Researchers have great expectations for the soon-to-launch NASA satellite that will provide an unprecedented map of carbon dioxide emissions on Earth.

Slated to launch on Tuesday from Vandenberg Air Force Base in California, the Orbiting Carbon Observatory will give scientists a more accurate depiction of concentrations of carbon dioxide in Earth's atmosphere.

Ground-based carbon dioxide monitoring efforts can only provide so much information, and NASA believes its orbiting observatory will fill in the information gaps.

The satellite will study the sources of carbon dioxide as well as carbon sinks "“ where it is absorbed in the oceans and forests. Previous information has suggested that these sinks could be spilling what has been absorbed back into the air.

"Something out there is changing dramatically," David Crisp, a scientist at the NASA Jet Propulsion Laboratory in Pasadena, Calif., and principal investigator of the mission, told the New York Times.

"The Orbiting Carbon Observatory will help scientists better understand what causes this variability and whether natural absorption will continue, stop or even reverse," NASA said in a statement.

Carbon dioxide is the leading cause of global warming. Humans are responsible for two percent of the world's carbon dioxide emissions. Emission levels before the beginning of the Industrial Revolution were near 280 parts per million. Today, the level is 387ppm with no expectation of decreasing anytime soon.

"If the nations of the world take serious action to limit the use of fossil fuels, the right to emit carbon dioxide will become scarcer, and emission rights would become an increasingly valuable traded commodity," said Phil DeCola, a senior policy analyst in the White House Office of Science and Technology Policy, and former Orbiting Carbon Observatory program scientist at NASA Headquarters in Washington.

"Observations of the location, amount and rate of carbon dioxide emission into the air, as well as the stock and flow of all forms of carbon on land and in the ocean, will be needed to manage such a world market fairly and efficiently."

The satellite will take 8 million carbon dioxide measurements every 16 days, NASA said, which will be a great improvement over the limited amount of information currently available from the small network of ground-based instruments, aircraft and limited space observations, the space agency said.

The orbiting observatory will use an instrument with three spectrometers to analyze light reflected off the Earth. The instrument will make a similar measurement for oxygen. Those measurements will be combined to depict the amount of carbon dioxide in the air.

This year marks the 50th anniversary of Scripps Institution of Oceanography scientist Charles David Keeling's Mauna Loa carbon dioxide record, the longest continuous record of atmospheric carbon dioxide measurements.

"The new mission will provide information to help develop and implement domestic policies and international collaborations to control the movement of carbon in the environment," said Edwin Sheffner, deputy chief of Earth Science at NASA's Ames Research Center, Moffett Field, Calif.

"By identifying and monitoring carbon sources and sinks within a given region, the Orbiting Carbon Observatory will enable comparisons of net carbon dioxide emission sources among regions and counties, and will improve annual reporting of carbon budgets by industrial countries in northern latitudes, and by tropical states with large forests."

"Future monitoring systems based on Orbiting Carbon Observatory technology could report on regional carbon sources and sinks to verify carbon reporting for many countries as well," he added.

The satellite is expected to launch at 4:51a.m. Eastern Time aboard a Taurus XL rocket to orbit some 438 miles above Earth. After which, the satellite will undergo months of calibration before observations are considered accurate.

"It's a brand new kind of science measurement," Dr. Crisp said. "It's going to take us a while to get the measurement right."


Image 1: This is an artist's concept of the Orbiting Carbon Observatory. The mission, scheduled to launch in early 2009, will be the first spacecraft dedicated to studying atmospheric carbon dioxide, the principal human-produced driver of climate change. It will provide the first global picture of the human and natural sources of carbon dioxide and the places where this important greenhouse gas is stored. Such information will improve global carbon cycle models as well as forecasts of atmospheric carbon dioxide levels and of how our climate may change in the future. Image credit: NASA/JPL

Image 2: NASA's Orbiting Carbon Observatory is on the launch pad at Vandenberg Air Force Base in California. Image credit: NASA/Randy Beaudoin


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