Monitoring of the Earth’s atmosphere

Over the last 40 years, the GIRPAS team has recorded at the Jungfraujoch station more than 60000 high-resolution infrared solar spectra, gathering a unique observational database, worldwide, in terms of measurement density, quality and time coverage.
Careful analysis of these observations allows us to determine the abundance of more than 30 key constituents of the Earth’s atmosphere, involved in stratospheric ozone depletion, contributing to the greenhouse effect and global warming, or atmospheric pollutants leading to air quality degradation.
Our reference time series are crucial tools for the determination of the long-term trends affecting the atmospheric composition and circulation as well as for the identification of the factors responsible for the observed changes.
Our research activities are mainly conducted within the framework of the international Network for the Detection of Atmospheric Composition Change (NDACC).

Validation and exploitation of satellite data

The GIRPAS has also been deeply involved in satellite missions monitoring the state of the Earth’s atmosphere, currently contributing to the exploitation of data produced by the ACE mission (Atmospheric Chemistry Experiment) of the Canadian Space Agency.
The team also regularly takes part to the validation and calibration of Earth-orbiting atmospheric sensors (e.g., ACE, IASI, MIPAS, OMI, SCIAMACHY).


Atmospheric modeling

Atmospheric modeling is another component of the group’s activities. We exploit the 3D-CTM (Chemistry Transport Model) model GEOS-Chem, in collaboration and with the support of Pr D.J. Jacob’s group at Harvard.
This model allows performing global atmospheric simulations very useful for data interpretation and for the realistic representation of the state of the atmosphere at horizontal resolutions as fine as 0.25° x 0.3125° (latitude x longitude)

Instrumental developments and microelectronics

The team is also much involved in instrumental developments applied to the Fourier Transform spectroscopy, with the constant aim of keeping the equipment at the state-of-the-art.
The applications include the design and implementation of systems allowing the remote operation of all the equipment, the improvement of the acquisition method of the spectrometer and of its efficiency, but also the building of the microelectronic devices needed to reach the required level of performance and reliability.