Progress on the World’s First Global Climate Reference Upper Air Network

Two developments in March 2009 will highlight progress in implementing the world’s first climate reference network for upper-air observations, the GCOS (Global Climate Observing System) Reference Upper Air Network (GRUAN). The first is an article to appear in the March 2009 issue of the Bulletin of the American Meteorological Society entitled “Reference Upper-Air Observations for Climate: Rationale, Progress, and Plans” by NOAA Air Resources Laboratory scientist Dian Seidel and co- authors. The article answers the basic “who, what, where, when, why, and how” questions about GRUAN and invites readers’ constructive feedback and participation in the new network. The article will be published both in the traditional paper format and in a new digital format, about to debut.

The second development is the holding of the first GRUAN Implementation-Coordination meeting, March 2-4, 2009 in Norman, Oklahoma. The meeting affords an opportunity for the Working Group on Atmospheric Reference Observations (operating under the GCOS Atmospheric Observation Panel for Climate), the GRUAN Lead Centre, and initial GRUAN candidate site representatives to review progress to date and to define the most practical mode of operation for GRUAN as measurement programs start to be implemented. The meeting will be hosted by the Cooperative Institute for Mesoscale Meteorological Studies, and by the US Department of Energy’s Atmospheric Radiation Measurement program Climate Research Facility, at its Southern Great Plains site. The Southern Great Plains site has been designated one of the first sites in the newly established GRUAN. Dian Seidel will attend the meeting as a member of the Working Group.

Background: NOAA scientists and program managers, and colleagues from around the world, have long recognized the need for climate-quality measurements of the vertical profile of temperature, humidity, winds, atmospheric composition, and radiation variables. NOAA’s Climate Program Office, US GCOS Program Office at NOAA’s National Climatic Data Center, Air Resources Laboratory, Earth System Research Laboratory, NESDIS, and NWS have joined with colleagues from the Department of Energy, the National Center for Atmospheric Research, and Howard University to provide leadership for GRUAN and to coordinate US contributions. The Global Climate Observing System program provided an international framework for developing network requirements, identifying sites and instrumentation, and coordinating national contributions. NOAA hosted workshops in 2005 and 2006 that laid the groundwork for GRUAN. The US is committed to the further progress in moving the GRUAN from concept to operations, and as such a US GRUAN Implementation Plan has been developed to address the US contribution to GRUAN, including seven designated US GRUAN stations. GCOS selected the Lindenberg Observatory in Germany as GRUAN Lead Center in 2007, and observations have begun there as of January 2009.

Significance: These developments provide gratifying evidence that, after more than a decade of discussion, a GCOS Reference Upper Air Network, to provide climate-quality measurements of tropospheric and lower stratospheric variables, is starting to become a reality. The GRUAN will provide long-term, continuous, high-quality in situ atmospheric profile observations for climate monitoring, calibration of satellite observations and products, and climate process studies. The GRUAN is an important contribution to the Global Earth Observation System of Systems.

For More Information, contact:Dr. Dian Seidel