A new challenge for meteorological measurements: The meteoMet project-Metrology for meteorology

Climate change and its consequences require immediate actions in order to safeguard the environment and economy in Europe and in the rest of world. Aiming to enhance data reliability and reduce uncertainties in climate observations, a joint research project called MeteoMet-Metrology for Meteorology started in October 2011 coordinated by the Italian Istituto Nazionale di Ricerca Metrologica (INRiM). The project is focused on the traceability of measurements involved in climate change: surface and upper air measurements of temperature, pressure, humidity, wind speed and direction, solar irradiance and reciprocal influences between measurands. This project will provide the first definition at the European level of validated climate parameters with associated uncertainty budgets and novel criteria for interpretation of historical data series. The big challenge is the propagation of a metrological measurement perspective to meteorological observations. When such an approach will be adopted the requirement of reliable data and robust datasets over wide scales and long terms could be better met. © 2013 AIP Publishing LLC

The IMERAPlus Joint Research Project For Determinations Of The Boltzmann Constant

Abstract. To provide new determinations of the Boltzmann constant, k, which has been asked for by the International Committee for Weights and Measures concerning preparative steps towards new definitions of the kilogram, the ampere, the kelvin and the mole, an iMERAPlus joint research project has coordinated the European activities in this field. In this major European research project the Boltzmann constant has been determined by various methods to support the new definition of the kelvin. The final results of the project are reviewed in this paper. Determinations of the Boltzmann constant k were achieved within the project by all three envisaged methods: acoustic gas thermometry, Doppler broadening technique, and dielectric constant gas thermometry. The results were exploited by the interdisciplinary Committee on Data for Science and Technology (CODATA) in their 2010 adjustment of recommended values for fundamental constants. As a result, the CODATA group recommended a value for k with a relative standard uncertainty about a factor of two smaller than the previous u(k)/k of 1.7×10 −6

The European Metrology Programme for Innovation and Research project: Implementing the new kelvin 2 (InK2)

The International System of Units (SI) is to be redefined with implementation set to be on World Metrology Day (20th May 2019). Under the auspices of the Consultative Committee of Thermometry (CCT) the world thermometry community has been working together to ensure a smooth and effective redefinition of the kelvin. A large part of that activity has been coordinated through the European Metrology Programme for Innovation and Research: "Implementing the new kelvin" projects. This paper describes the InK2 project contribution

An Adiabatic Calorimeter for the Realization of the ITS-90 in the Cryogenic Range at the LNE-CNAM

The LNE-CNAM, in cooperation with the IPN, has recently developed a new cryogen-free adiabatic calorimeter, to realize the International Temperature Scale of 1990 (ITS-90) in the temperature range between 6 K and 84 K. The new calorimeter, cooled by a closed-cycle Gifford-McMahon refrigerator, is equipped with three thermal shields and two separate vacuum chambers, to minimize the effect of parasitic heat fluxes. The inner adiabatic chamber can accommodate either a multi-compartment cell--containing the triple points of hydrogen, neon, oxygen, and argon, to realize the ITS-90 between 14 K and 84 K--or a comparison block for thermometers, the calibration of rhodium-iron (RhFe) thermometers between 6 K and 24 K. The use of a cryogen-free system and a fully computer-controlled measurement chain allow long lasting experiments and good thermal control, resulting in a substantial reduction of the measurement uncertainties. The new adiabatic calorimeter has been successfully tested at the LNE-CNAM. The overall standard uncertainties in the realization of the ITS-90 have been reduced from 2.08 mK to 0.37 mK at the hydrogen triple point, from 1.40 mK to 0.30 mK at the triple point of neon, and are maintained below 0.26 mK at the triple points of oxygen and argon. In the temperature range between 6 K and 24 K, calibrations of rhodium-iron resistance thermometers have been carried out with a standard uncertainty of the order of 0.80 mK

Guide to the Realization of the ITS-90 - Metal Fixed Points for Contact Thermometry

This paper is a part of guidelines, prepared on behalf of the Consultative Committee for Thermometry, on the methods for realizing the International Temperature Scale of 1990 (ITS-90). It describes ways of realizing the defining fixed points of the ITS-90 which comprise metal fixed points for contact thermometry

Report presented to the CCT by Working Group 1: April 2012

Activity report of Working Group 1