Airborne measurement of reactive species in the free troposphere is one of the more recent lines of research initiated by TROLAS with the development of a PeRCA instrument to be deployed in an airborne platform. i.e. a
DUal channel Airborne peroxy radica L chemical amplifier (DUALER). Peroxy radicals can be of especial importance in the free troposphere owing to their central role in the oxidation processes leading to rapid and effective formation of O3, PAN (peroxy acetyl nitrate) aldehydes and acids.
The first DUALER instrument developed by the TROLAS group was successfully deployed on the
Falcon scientific aircraft of the DLR during the field campaign of the African Monsoon Multidisciplinary Analysis (AMMA) taking place in Burkina Faso 2006.
The extensive experience gained with airborne platforms has provided a solid basis for development of the DUALER instrument up to the present. In particular, the drawbacks of the luminol detector for the measurement at low atmospheric pressures showed the necessity of a novel high sensitive NO2 detector to enable the measurement of peroxy radicals in the upper troposphere. This became the main objective of the project REVOLVER
(Peroxy Radical MEasurement based on Optical Feedback CaVity Enhanced AbsOrption Spectroscopy and ChemicaL ConVERsion and Amplification and NO2 measurement based on an OF-CEAS system). Result of this research is the airborne PeRCEAS (Peroxy Radical Chemical Enhancement and Absorption Spectrometer) instrument which has been successfully deployed on the HALO scientific aircraft of the » DLR within the OMO measurement campaign.
TROLAS will moreover have the opportunity to investigate the vertical distribution of the peroxy radicals in the lower layers of the troposphere within the project VERDRILLT (
VERtical Distribution of Radicals In the Lower Layers of the Troposphere) partly funded in the framework of EUFAR ( European Facility for Airborne Research). In that context, a measurement campaign involving the deployment of the DUALER in the CASA 212 AR aircraft of the INTA ( Instituto Nacional de Tecnica Aeroespacial) was carried out August 2010 in Spain.