Airborne imaging differential optical absorption spectroscopy: Trace-gas measurements from the suburbs to the sub-continent

A remote sensing instrument for high-resolution measurement of two dimensional trace-gas distributions from an aircraft has been built. The instrument has been tested during three measurement campaigns over the South African High-veld region. The resolution achieved is less than 100 metres, allowing point sources to be clearly identified. Measurements have been interpreted with respect to emission flux and oxidation of species in the atmosphere. The high speed of the aircraft also allows measurements to be made on a regional scale.