Evidence of localized strong enhancements in lower stratospheric CH3CN following intense forest fire activity

On 24 August 1992, the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite observed a significant enhancement in the abundance of lower stratospheric methyl cyanide at approximately 16-19 km in altitude in a small region off the coast of Florida. Concentrations of order 1400 parts per trillion by volume were observed, compared to a typical stratospheric background level of 30 pptv.