GCOS Reference Upper-Air Network

Former Task Team on Ancillary Measurements

A Task Team of AOPC Working Group on GRUAN (WG-GRUAN)

The Task Team on Ancillary Measurements has been divided into two new separate teams: Task Team on Satellite-Based Remote Sensing Measurements (TT-SAT) and Task Team on Ground-Based Remote Sensing Measurements (TT-GB). Both new teams are in the formation phase now.


The GCOS/WCRP Atmospheric Observation Panel for Climate (AOPC) Working Group on the GCOS Reference Upper Air Network (GRUAN) was established in 2006 in recognition of the importance of initiating reference-quality observations of atmospheric column properties, in particular temperature and water vapour, from the surface into the stratosphere to enhance the monitoring and understanding of climate variability and change. A GRUAN Implementation Plan was published in July 2009 covering the period until 2013. At the second Implementation and Coordination Meeting held in Payerne, Switzerland in March 2010 the Working Group, Lead Centre and initial sites agreed to the instigation of a number of task teams.

The task team on Ancillary measurements exists to define protocols, sampling strategies and required metadata for respective suites of ancillary ground and satellite measurements routinely collected and archived at GRUAN sites.  Ancillary in this respect is defined as measurements at a given GRUAN site that do not fall under the set of required observations from all sites, for example the reference radiosonde. Ancillary in this sense also includes required respective instrument calibration, inter-validation strategies and results and all metadata pertinent to the deployed equipment and associated measurement suites. These shall be compiled utilizing best measurement practices as defined through associated measurement international expert team representation in this group. Practices and protocols for respective measurement suites as defined by this group shall constitute guidelines for respective site and measurement certification.


Under the auspices of the WG-GRUAN the task team was established to:

Reporting and governance



(as at 2020-09-16)

Name Organisation
Thierry Leblanc (co-chair) NASA/JPL, US
Lori Borg (co-chair) University of Wisconsin-Madison, US
Alexander Haefele Meteoswiss-Payerne, CH
Nik Kämpfer University Bern, CH
Jim Hannigan NCAR, US
Matthias Schneider KIT/IMK-ASF and AEME, DE
Marc Schröder DWD, DE
Michael Sommer DWD, DE
John Dykema Harvard University, US
Jonathan Gero AERI, US

Presentations and Reports

Terms of reference