Scientists to Measure Greenhouse Gas Emissions Over North America

Government and university scientists will be hanging out at the track this summer — only there aren't any horses and the track is located 30,000 feet above sea level. (Click image for larger view of COBRA (CO2 Budget and Regional Airborne Study) 2003 'racetrack.' CREDIT: NOAA)

The 'racetrack' is a pattern that a highly instrumented University of North Dakota Cessna Citation aircraft will fly over the central portion of North America to measure greenhouse gas emissions. Researchers plan to measure the concentrations of a variety of gases, such as carbon dioxide and sulfur hexafluoride, over a major portion of North America, from late May through June 2003. The scientists will combine the aircraft data with high-resolution winds to determine the emission rates for major greenhouse gases over the continent during the month of the experiment.

The flights will also include measurements of ozone-depleting gases and other pollutants from the New York City-Washington, D.C. metropolitan corridor, Denver, Boston, and Dallas. There will be excursions over the Pacific Ocean from Eureka, Calif., and over the Atlantic from Pease, N.H., to Sable Island, to examine coastal influence of marine air and the mixing processes between maritime and continental air. (Click image for larger view of COBRA first test flight through Denver's pollution and haze layer taken May 23, 2003. CREDIT: NOAA)

James Elkins, a researcher at the NOAA Climate Monitoring and Diagnostics Laboratory in Boulder, Colo., and a principal investigator on the project, says "This mission will enable us to map the emissions of both ozone depleting and greenhouse gases across the U.S. and Canada in a way we've never been able to do before."

Called COBRA (CO2 Budget and Regional Airborne Study), the experiment will also rely upon the extensive ground-based data from the NOAA Cooperative Station Networks for carbon cycle and halocarbon trace gases, the Fluxnet Canada research network and the AmeriFlux network of ground stations. (Click image for larger view of North Dakota Cessna Citation aircraft taking off from Jefferson County Airport in Broomfield, Colo., on first test flight through Denver's pollution taken May 23, 2003. CREDIT: NOAA)

"The flight plan is very ambitious," said Elkins. "As the aircraft flies over the ground stations, vertical profiles will be taken that will provide important data on the boundary conditions for the flow of air through the area of the racetrack and for atmospheric mixing." Previous studies have identified a large land area that absorbs CO2 in North America. COBRA will provide a critical test for these ideas.

One of the most important problems in forecasting future climate change is to improve predictions of future concentrations of greenhouse gases in the atmosphere. "Currently we lack the capability to accurately measure the sources and sinks of greenhouse gases from large land areas such as North America," says project scientist Steven Wofsy of Harvard.

"This type of measurement is essential for accurate predictions of the future. The COBRA program is designed to make detailed observations in the atmosphere and allow us to determine large-scale sources and sinks." The racetrack was chosen to encompass a large 'sink' of CO2 that occurs over North America during the peak growing season for vegetation.

Contacts:

Barbara McGehan
NOAA Research
303-497-6288

Photos Courtesy of James Elkins, researcher at the NOAA Climate Monitoring and Diagnostics Laboratory in Boulder, Colorado

Location:

The project runs until June 23, 2003, and is baed at Jefferson County Airport in Broomfield Colo., and at Pease, N.H.

Participants:

• The NOAA Climate Monitoring and Diagnostics Laboratory
• Harvard University
• The National Center for Atmospheric Research
• The University of North Dakota
• The University of Colorado Cooperative Institute for Research in Environmental Sciences and the Scripps Institution of Oceanography
• and Scientists at the University of Sao Paulo, Brazil, will collaborate by providing detailed winds and meteorology from their Brazilian Regional Atmospheric Modelling System (BRAMS)

Schedule:

Scientists are scheduled to depart for Greenland on a NASA P-3B aircraft from the NASA Goddard Space Flight Center's Wallops Flight Facility, Wallops Island VA., on May 7. During the next four weeks, through early June, the scientists will survey the Greenland ice sheet in the southern and northern parts of the island.

Funding:

Principal funding is being provided by NASA's Terrestrial Ecology Program, headed by Diane E. Wickland, with additional funds from the NOAA Climate Monitoring and Diagnostics Laboratory and the Office of Global Programs, NASA's Upper Atmosphere Research and Atmospheric Chemistry Modeling Analysis Programs, the National Science Foundation's Atmospheric Chemistry Program, and the Department of Energy's Terrestrial Carbon Program.

Website:

• http://www.fas.harvard.edu/~cobra/
• http://www.noaanews.noaa.gov/stories/s1151.htm
• NOAA Climate Monitoring and Diagnostics Laboratory
• NOAA Office of Global Programs