Trace gas retrieval software

The experience of BIRA-IASB in the development and improvement of algorithms for the retrieval of trace gas concentrations goes back to the early 1990s, with atmospheric research activities using ground-based UV-Visible spectrometers aiming at the long-term monitoring of minor components involved in the catalytic destruction of the ozone layer or in anthropogenic pollution.

The development of various ground-based and satellite-based instruments has made it necessary to develop general software for trace gas retrieval. Below follows a short overview of the software packages that are also available for others to use.

 

QDOAS

QDOAS is a cross-platform implementation of WinDOAS i.e. that the software is portable to Windows and Unix-based operating systems. The user interface is the same on these platforms, and is very similar to that of WinDOAS. The DOAS engine is also the same as WinDOAS one. So people already familiar with WinDOAS should move easily to QDOAS.

QDOAS is developed in collaboration with S[&]T, a Dutch company well-known for the development of cross-platform products and software tools for the processing of satellite measurements. The graphical user interface is built on the Open-Source version of the QT-4 toolkit, a cross-platform application framework, and QWT plot libraries. QDOAS is also open source. The source code can be obtained by contacting authors.

Last release : 2.00, 5 March 2012

More details about QDOAS

 

GODFIT & GDOAS, SDOAS

In collaboration with Rob Spurr of RT Solutions Inc. a software package currently called GODFIT is under development. This package performs trace gas retrieval using a direct fitting approach: radiative transfer calculations are used to find the total concentration of a trace gas by way of optimal estimation. In addition this package can perform a traditional DOAS retrieval, followed by a radiative transfer calculations to determine the total concentration. The GDOAS and SDOAS packages are special split-off applications of GODFIT.

Since GODFIT is currently under development, it is not yet available to others.

 

Tools

Some specific tools which could be of use to others are provided via a separate page.