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GCOS Cascade of upper-air networks

GCOS Reference Upper-Air Network (GRUAN)

GCOS is establishing a reference network for upper-air climate observations (GRUAN).

GRUAN is expected to provide long-term, highly accurate measurements of the atmospheric profile, complemented by ground-based state of the art instrumentation, to constrain and calibrate data from more spatially-comprehensive global observing systems (inc. satellites and current radiosonde networks), in order to fully characterize the properties of the atmospheric column and their changes.

GRUAN is envisaged as a network of 30-40 high-quality, long-term, upper-air observing stations, building on existing observational networks, such as NDACC, ARM, GUAN, GAW, BSRN and GSN. GRUAN builds on, but is not confined to, the larger GCOS Upper Air Network (GUAN).

In 2007, the GRUAN Lead Centre has been assigned to the Richard-Assmann-Observatory at Lindenberg, Germany. The GRUAN Lead Centre is responsible for the coordination among stations, including training, education and research, and ensuring the archival and dissemination of GRUAN Data.

For further information, visit the official GRUAN Website, maintained by the GRUAN Lead Centre.

GRUAN outreach material

GRUAN organising chart

GRUAN measurement sites

Workin Group on GRUAN

GRUAN-related documents

• Report of the 4th GRUAN Implementation and Coordination Meeting (ICM-4), Tokyo, Japan, March 2012 (PDF)
• Report from the WIGOS Pilot Project Meeting on GRUAN Observing Practices and Governance, Geneva, Switzerland, 25-27 February 2012(PDF)
• Report of the 3rd GRUAN Implementation and Coordination Meeting (ICM-3), Queenstown, New Zealand, February/March 2011 (PDF)
• Report of the 2nd GRUAN Implementation and Coordination Meeting (ICM-2), Payerne, Switzerland, March 2010 (PDF)
• GRUAN Implementation Plan 2009-2013, July 2009 (PDF)
• GRUAN Data Policy, Feb 2009 (PDF)
• Report of the 1st GRUAN Implementation and Coordination Meeting (ICM-1), Norman, Oklahoma, USA, March 2009 (PDF)
• Report of the GCOS Reference Upper-Air Network Implementation Meeting, Lindenberg, Germany, Feb 2008 (PDF)
• GCOS Reference Upper-Air Network (GRUAN): Justification, requirements, siting and instrumentation options; Apr 2005 (PDF)
• Seidel, D., Reference Upper-Air Observations for Climate: Rationale, Progress, and Plans. Bulletin of the American Meteorological Society, March 2009 (PDF)
• Press Release "New Radiosonde to Shed Light on Climate Change", Feb 2009 (PDF)
• GRUAN Manual Repository