1. 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
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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
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3. Focus on Reference observation
A GRUAN reference observation:
Is traceable to an SI unit or an accepted standard
Provides a comprehensive uncertainty analysis
Maintains all raw data
Is documented in accessible literature
Is validated (e.g. by intercomparison or redundant observations)
Includes complete meta data description
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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
Priority 1: Water vapor, temperature, (pressure and wind)
Priority 2: Ozone, …
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5. GRUAN Data Product: RH uncertainty
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6. Redundant Observations: CFH and GRUAN RS92
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7. GRUAN Data Product: RH uncertainty
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8. GRUAN Data Product: RH uncertainty
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9. Redundant Observations: CFH and GRUAN RS92
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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)
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GRUAN Needs
GRUAN has a strong need for colleagues to use GRUAN data and to provide feedback.
Data can be accessed through
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