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Abstract
In December 2006, severe forest fires raged in southeastern Australia. On 14 December 2006 a passing cold front in combination with the intense heat from the fires caused pyro-convective lofting and injected an intense pollution plume into the jet stream. We use Absorbing Aerosol Index (AAI) observations from the Ozone Monitoring Instrument (OMI) to track the transport of this plume, which circumnavigated the globe in 12 days. The OMI O2-O2 cloud retrieval algorithm was used to establish that in the first days after its release the plume resided near the tropopause at 200-300 hPa. The CALIOP spaceborn lidar confirmed the altitude of the plume to be 10-15 km. Simulations with the TM4 Chemistry Transport Model (CTM) matched the AAI observations and the vertical distribution from CALIOP for an injection height of 250 hPa. This high injection altitude mimics the pyroconvective lofting which is typically not accounted for in CTMs. This exceptional event is the first ever recording of around the world long range transport of forest fire emissions in the extratropical Southern Hemisphere.