1. Retrieval and validation of carbon dioxide, methane and water vapor for the Canary Islands IR-laser occultation experiment.
- Author
-
Proschek, V., Kirchengast, G., Schweitzer, S., Brooke, J. S. A., Bernath, P. F., Thomas, C. B., Wang, J.-G., Tereszchuk, K. A., González Abad, G., Hargreaves, R. J., Beale, C. A., Harrison, J. J., Martin, P. A., Kasyutich, V. L., Gerbig, C., Kolle, O., and Loescher, A.
- Subjects
CARBON dioxide & the environment ,METHANE & the environment ,WATER vapor ,LASER atmospheric observations ,GREENHOUSE gases ,INFRARED lasers ,ISLAND ecology - Abstract
The first ground-based experiment to prove the concept of a novel space-based observation technique for microwave and infrared-laser occultation between low-Earthorbit satellites was performed in the Canary Islands between La Palma and Tenerife. For two nights from 21 to 22 July 2011 the experiment delivered the infrared-laser differential transmission principle for the measurement of greenhouse gases (GHGs) in the free atmosphere. Such global and long-term stable measurements of GHGs, accompanied also by measurements of thermodynamic parameters and line-of-sight wind in a self-calibrating way, have become very important for climate change monitoring. The experiment delivered promising initial data for demonstrating the new observation concept by retrieving volume mixing ratios of GHGs along a ∼ 144 km signal path at altitudes of ∼ 2:4 km. Here, we present a detailed analysis of the measurements, following a recent publication that introduced the experiment's technical setup and first results for an example retrieval of CO
2 . We present the observational and validation data sets, the latter simultaneously measured at the transmitter and receiver sites; the measurement data handling; and the differential transmission retrieval procedure. We also determine the individual and combined uncertainties influencing the results and present the retrieval results for12 CO2 ,13 CO2 , C18 OO, H2 O and CH4 . The new method is found to have a reliable basis for monitoring of greenhouse gases such as CO2 , CH4 , and H2 O in the free atmosphere. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF