Plans of the GCOS Reference Upper Air Network

Plans of the GCOS Reference Upper Air Network (GRUAN) Holger Vömel, GRUAN Lead Center DWD Meteorological Observatory Lindenberg U. S. – Japan Workshop on the Tropical Tropopause Layer 17 October 2012 www. gruan. org Meteorological Observatory Lindenberg -1 -

What is GRUAN? · GCOS Reference Upper Air Network · Ground based network for reference observations for climate within GCOS, with current focus on water vapor and temperature (troposphere and stratosphere) · Currently 16 sites, with aim to expand to 30 to 40 sites worldwide Check out www. gruan. org Meteorological Observatory Lindenberg -2 -

Focus on Reference observation A GRUAN reference observation: ü Is traceable to an SI unit or an accepted standard ü Provides a comprehensive uncertainty analysis ü Maintains all raw data ü Is documented in accessible literature ü Is validated (e. g. by intercomparison or redundant observations) ü Includes complete meta data description www. gruan. org Meteorological Observatory Lindenberg -3 -

GRUAN goals · Maintain observations over decades · Validation of satellite systems · Characterize observational uncertainties · Traceability to SI units or accepted standards · Comprehensive metadata collection and documentation · Long-term stability through managed change · Validate observations through deliberate measurement redundancy www. gruan. org Priority 1: Water vapor, temperature, (pressure and wind) Priority 2: Ozone, … Meteorological Observatory Lindenberg -4 -

GRUAN Data Product: RH uncertainty www. gruan. org Meteorological Observatory Lindenberg -5 -

Redundant Observations: CFH and GRUAN RS 92 www. gruan. org Meteorological Observatory Lindenberg -6 -

GRUAN Data Product: RH uncertainty www. gruan. org Meteorological Observatory Lindenberg -7 -

GRUAN Data Product: RH uncertainty www. gruan. org Meteorological Observatory Lindenberg -8 -

Redundant Observations: CFH and GRUAN RS 92 www. gruan. org Meteorological Observatory Lindenberg -9 -

GRUAN Plans in the TTL · Focus on routine observations in the TTL at GRUAN sites · Improve the data quality of the operational soundings + Improved operational procedures + All known corrections operationally applied + Aim for best possible P, T, RH + But need access to raw data in real time · Start regular CFH launches at one site (Manus) · Elevate ozone observations to GRUAN level (uncertainties) · Can provide platform for campaign based data processing (done Ougadougou, Gan, currently collecting San Cristobal, could also process Costa Rica/Alajuela) www. gruan. org Meteorological Observatory Lindenberg - 10 -

GRUAN Needs F GRUAN has a strong need for colleagues to use GRUAN data and to provide feedback. F Data can be accessed through www. gruan. org/data www. gruan. org Meteorological Observatory Lindenberg - 11 -