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Into the Future with Metrology - The Challenges of Our Environment and Climate


The atmosphere: the air around us

The GLORIA infrared Fourier spectrometer
The GLORIA infrared Fourier spectrometer is regularly taken on the various missions of the German Aerospace Center's HALO research aircraft. It can carry out more than 16,000 spatially and spectrally resolved atmospheric observations simultaneously and is regularly recalibrated by PTB.

A key task of climate monitoring is the observation of the most important atmospheric components that influence the greenhouse effect. In addition to using ground stations and satellites, the WMO's Global Atmosphere Watch (GAW) Programme also takes measurements in the atmosphere, for example using aircraft, balloons and drones. In all of these fields, PTB provides metrological support. PTB is active in the SI traceability of the measurement of H2O, CO2, CH4, N2O, volatile organic compounds (VOCs) and soot aerosols. It develops national standards and measurement procedures for this purpose, for example, on the basis of optical-spectroscopic measurements with tunable lasers or Fourier Transform Infrared Spectrometers (FTIRs). Another important topic is innovative aerosol metrology up to primary particle number standards or the traceability of black carbon measurements. Where the calibration of optical spectrometers is not possible (or where stable, SI-traceable reference gases are not available), PTB offers the most important input quantity for spectroscopic remote sensing measurements by measuring spectral reference data of the important molecules. At the same time, PTB develops accurate, calibration-free laser spectrometers as metrological transfer standards that, if required, can also be designed in such a way that they can be used in the field – for example, on research aircraft such as Opens external link in new windowHALO – It is intended to further expand the fascinating possibilities of spectroscopic transfer standards, absolute spectral data and aerosol metrology.

For many years, PTB has also ensured the traceability of airborne remote sensing measurements with regard to the composition and dynamics of the atmosphere. These measurements are performed during the various missions of the GLORIA imaging infrared Fourier spectrometer of Forschungszentrum Jülich (FZJ) and the Karlsruhe Institute of Technology (KIT) on the HALO research aircraft. For the global ground-based measurements of the infrared reflection of the atmosphere performed within the framework of the worldwide Baseline Surface Radiation Network (BSRN), PTB has developed and implemented a traceability concept in cooperation with the World Radiation Center in Davos, thus allowing it to continue ensuring the comparability of these measurements in the future.

Participating departments and working group

Opens internal link in current window3.4 Analytical Chemistry of the Gas Phase

Opens internal link in current window7.3 Detector Radiometry and Radiation Thermometry

Opens internal link in current window 7.32 Infrared Radiation Thermometry