METEOMET: metrology for data quality in climate and meteorological observations

In October 2011, a joint research project called "MeteoMet - Metrology for Meteorology" (www.meteomet.org) started, bringing together a wide consortium of partners: 18 national metrology institutes and 6 universities as partners plus 29 collaborators, including national meteorological organizations, research institutes associations and instruments companies. The project is aiming to respond to the needs for new stable and traceable measurement standards, protocols, sensors and calibration procedures, and uncertainty-evaluation methods, to enhance data reliability and reduce uncertainties in climate models. This project is part of the European Metrology Research Program (EMRP) coordinated by the European Association of National Metrology Institutes (EURAMET). The activities that are on their full way now, comprise of investigation of new humidity sensors for upper air measurements with setting up a traceability chain based on tuneable diode laser absorption spectroscopy (TDLAS); development of novel methods and instruments for the measurement of temperature, humidity, and pressure in lower and upper atmosphere; development of traceable measurements methods and protocols for temperature, humidity, pressure and airspeed ground-based measurements needed for climate studies and meteorological long-term and wide scale observations; etc. Additionally, the project deals also with the construction of a facility for in-situ traceable calibration of weather stations. Three models of this facility have been developed for different uses, including extreme environmental conditions: one of those chambers will be transported and used at the Pyramid laboratory/observatory of Mount Everest, for the calibration of sensors positioned in the Himalayan area. As the project will terminate in 2014, initial steps were already taken to start a follow-up project, which will place even more focus on alpine meteorological issues related to metrology. At present, several high mountain stations located mainly in alpine environment are run by different services or institutions without commonly agreed procedures for measurements, instruments involved and site characteristic, which hardly complies with the WMO directive. The particularity of high mountain environment requires new kind of site and instrument validation processes. A proposed reference station in high mountain alpine area, combined with other kind of monitoring (permafrost, water lakes/springs, etc.), is necessary in order to analyse the best way the relationship among atmosphere, geosphere, cryosphere, hydrosphere and biosphere in alpine region, particularly sensitive to climate change and where their effects are more pronounced. A pilot surface site in support of high mountain programs and in conjunction with the permafrost monitoring network would improve the quality of weather and climate parameters recorded in high alpine. The evaluation of mutual relations at seasonal, annual, long-term level would be possible. For the measurement of the high mountains lakes temperature of the water and ice mantles it is proposed the definition of specific systems, best practice, calibration and measurement uncertainty evaluation, for a practical reference example to be implemented through instruments and calibration campaigns. Dedicated instruments calibration for temperature and soil moisture probes and assessment of calibration and measurement uncertainty are proposed too. A methodology to achieve calibration target uncertainty in the order of 0.01 °C is proposed for permafrost monitoring studies. The adoption of standard equipment and procedures for alpine stations, would benefit the work of the European nations belonging to the Alps Convention in their common mission of climate and weather observations. These ambitious objectives are planned to be discussed also in the scope of a first International workshop on traceability and uncertainty evaluation for meteorology, climatology and earth observations which is scheduled for late spring 2014.