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FIRE Arctic Cloud Experiment (ACE) |
FIRE, the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment, is going to the Arctic to study a variety of Arctic cloud systems under spring and summer conditions. A team of national and international scientists will conduct the FIRE Arctic Cloud Experiment (ACE) in a two-phase field campaign, starting in April, 1998, and a second phase to be conducted during July, 1998.
The scientific objectives of FIRE.ACE will be to study impact of Arctic clouds on radiation exchange between surface, atmosphere, and space, and the influence of surface characteristics of sea ice, leads, and ice melt ponds on these clouds. FIRE.ACE will attempt to document, understand, and predict the Arctic cloud-radiation feedbacks, including changes in cloud fraction and vertical distribution, water vapor cloud content, cloud particle concentration and size, and cloud phase as atmospheric temperature and chemical composition change. FIRE.ACE will use the data to focus on improving current climate model simulations of the Arctic climate, especially with respect to clouds and their effects on the surface energy budget. In addition, FIRE.ACE will address a number of scientific questions dealing with radiation, cloud microphysics, and atmospheric chemistry.
The strategy of FIRE.ACE is to use aircraft to take remote and in situ measurements of the Arctic cloud and surface characteristics. The NASA ER-2 will fly far aloft with a suite of remote sensors to remotely infer the cloud and radiative properties of the clouds that form in the vicinity of leads and melt ponds. The University of Washington Convair 580, National Center for Atmospheric Research C-130, and Canada National Research Council Convair 580 aircraft each will fly with a number of in-situ instruments to measure the optical, physical, radiative, and chemical properties of the clouds and radiation directly.
The aircraft observations will be made over surface measurements provided by FIRE, SHEBA (Surface Heat Budget of the Arctic Ocean), and ARM (Atmospheric Radiation Measurements). SHEBA, which is sponsored by the National Science Foundation (NSF) and the Office of Naval Research (ONR), is a research program designed to document and understand the physical processes that couple the atmosphere, ice, and ocean in the Arctic. It is currently conducting a year-long extensive set of measurements directly on, under, and above the sea ice in the Beaufort sea, using the Canadian Coast Guard ice breaker Des Groseilliers as a permanent ice station. The ARM program is sponsored by the Department of Energy (DOE) to resolve scientific uncertainties about global climate change with a specific focus on improving the performance of general circulation models used for climate research and prediction. ARM is providing a number of key surface-based remote sensing instruments specifically designed for the measurements of clouds and radiation at the SHEBA ice station. ARM is also operating a duplicate set of instruments at Barrow, Alaska, as part of a decade-long program to measure the clouds and radiation in the Arctic Basin.
The Arctic Cloud Experiment, in collaboration with SHEBA and ARM, represents an important broadening of the scientific scope and the experiences of the FIRE program as a whole. This strategic step is motivated by the acknowledged importance of the Arctic for the global climate system, and an appreciation of how poorly we understand Arctic clouds and the energy budget of the Arctic surface. The emphasis will be on aircraft measurements, with surface data being provided primarily by SHEBA and ARM and partially by FIRE. Satellite observations will also be obtained in concert with the aircraft and surface measurements.
The Langley Research Center Distributed Active Archive Center (DAAC) will provide a web site to report experiment status in real time during the campaign, and the DAAC provides a centralized data holding and on-line system to facilitate easy access to all the FIRE III data once they are collected and archived.
Detailed information on FIRE.ACE, as well as the other FIRE projects, can be found on the FIRE Home Page at: http://asd-www.larc.nasa.gov/fire.
The National Aeronautics and Space Administration (NASA) serves as the lead agency for FIRE. Other supporting agencies are the NSF, ONR, DOE, National Oceanic and Atmospheric Administration (NOAA), and Department of Defense (DOD). Over 80 researchers from seven NASA centers, four U.S. agencies, and nine U.S. universities, as well as scientists from Canada, Great Britain, and the Netherlands, will participate. FIRE is managed by the Radiation Sciences Program, Office of Earth Science, NASA Headquarters; the FIRE project management is located at Langley Research Center.
Purpose: Study impact of Arctic clouds on radiation exchange between surface, atmosphere, and space and influence of surface characteristics (including sea ice and leads) on these clouds.
Time:Location: Beaufort Sea
Participants: Scientists from U.S., Canada, Great Britain, and Netherlands.
Collaborating Experiments:Experiment Plan: Aircraft, surface-based, and satellites will be used to measure the physical processes of coupling between clouds, radiation, chemistry, and the atmospheric boundary layer over the Arctic sea ice in the Beaufort Sea and over Barrow, Alaska.
Points of Contact:
Robert Curran, Radiation Sciences Program Manager, Office of Earth Science, NASA Headquarters, Code YS, Washington, DC, 20546, Telephone 202-358-1432, Email rcurran@hq.nasa.gov.
David S. McDougal, FIRE Project Manager, NASA Langley Research Center, Mail Stop 483, Hampton, VA, 23681, Telephone 757-864-5832, Email d.s.mcdougal@larc.nasa.gov.
Judy Curry, Arctic Cloud Lead Scientist, Department of Aerospace Engineering Sciences, University of Colorado, Boulder, CO, Telephone 303-492-6417, Email curryja@cloud.colorado.edu.
The aircraft measurements will be made in the vicinity of the SHEBA ice station, currently located at 76 degrees N and 165 degrees W, and Barrow, Alaska. The Operation center will be located at Fairbanks, as will the NASA ER-2 and NCAR C-130 aircraft. The Canadian NRC CV-580 will be based at Inuvik, Canada, and the University of Washington CV-580 at Barrow.
