You must have a javascript-enabled browser and javacript and stylesheets must be enabled to use some of the functions on this site.


Detecting Volatile Organic Compounds from Orbit

Jeremy Harrison(1) and Peter Bernath(1)

(1) University of York, Heslington, York YO10 5DD, United Kingdom


Volatile organic compounds (VOCs) are responsible for air pollution. In recent years it has become possible to detect tropospheric VOCs using satellite instruments such as the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS). The ACE-FTS is a high resolution (0.02 cm-1) instrument covering the 750-4400 cm-1 spectral range in solar occultation mode. ACE was launched by NASA in August 2003 and the FTS continues to operate without any degradation in performance. The primary ACE mission goal is the study of ozone chemistry in the stratosphere although it is making a wide range of other measurements, for example the detection of VOCs such as methane, methanol, formaldehyde, ethane, ethene and ethyne.

The ACE-FTS records spectra in the 3 micron region, which is particularly suitable for the retrieval of hydrocarbons. The ethane spectrum is very strong in this region, however the existing HITRAN line parameters are not satisfactory. New high-resolution laboratory spectra of ethane have therefore been recorded for the range of temperatures and pressures needed for atmospheric retrievals. In a similar manner, spectra have been recorded for other VOCs, such as propane. Retrievals of VOCs will be presented using these laboratory spectra in the form of cross sections.