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Aerosol boomerang: Rapid around-the-world transport of smoke from the December 2006 Australian forest fires observed from space. Ruud Dirksen, KNMI Folkert Boersma, Jos de Laat, Piet Stammes. 14 December 2006: severe forest fires in SE Australia release aerosol boomerang
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Aerosol boomerang: Rapid around-the-world transport of smoke from the December 2006 Australian forest fires observed from space Ruud Dirksen, KNMI Folkert Boersma, Jos de Laat, Piet Stammes ISTP 2009 - 22 Oktober 2008
14 December 2006: severe forest fires in SE Australia release aerosol boomerang • Pyroconvective lofting facilitated long range transport • Determine the plume’s altitude: OMI O2-O2, CALIOP, TM4 • Conclusions ISTP 2009 - 22 Oktober 2008
Meteorological situation 14 Dec 2006 Weathermap of 14 December 2006, 1600 LT Cold front passing over fire location ISTP 2009 - 22 Oktober 2008
The Victoria blowup 14 Dec 2006 Observed by MODIS ISTP 2009 - 22 Oktober 2008 Courtesy M. Fromm
OMI O2-O2 cloud algorithm Absorption & scattering • O2-O2 collision complex @477nm, pressure dependent • Measures air column above cloud • Linedepth cloud height • Background cloud fraction ISTP 2009 - 22 Oktober 2008
TM4 tropopause Altitude information O2-O2 Source region NZ • Adjacent clouds: 1-5km • Scene pressure of plume itself yields higher altitudes OMI RGB 15 Dec ISTP 2009 - 22 Oktober 2008
Evolution of the plume Orbit 12924 Orbit 12953 TM4 tropopause TM4 tropopause 21 Dec 19 Dec Cloudless High Clouds CALIPSO footprint ISTP 2009 - 22 Oktober 2008
14 Dec 15 Dec 17 Dec 16 Dec 18 Dec 19 Dec 21 Dec 20 Dec 22 Dec 23 Dec 24 Dec 25 Dec TM4 simulation Passive tracer Water soluble Injection height 248 hPa (~10km) reproduces OMI AAI observations CTMs don’t incorporate latent heat from fires, emissions released at ground level ISTP 2009 - 22 Oktober 2008
CALIOP CALIOP CALIOP TM4 profiles for various injection heights Injection height 248 hPa gives best agreement with CALIOP observations ISTP 2009 - 22 Oktober 2008
Injection height High resolution 1-D plume rise model to simulate lofting of the plume by pyro-convection Input: Meteorological conditions at fire location on 14 Dec 2006 Fire front intensity, latent heat Courtesy Maria Val Martin ISTP 2009 - 22 Oktober 2008
20 Dec 20 Dec 21 Dec 21 Dec 22 Dec 22 Dec 23 Dec 23 Dec 24 Dec 24 Dec TM4 captures evolution and removal of the plume TM4 simulations with water soluble tracer show the removal of the plume by scavenging. Model the whole life cycle of the event Water soluble tracer passive tracer ISTP 2009 - 22 Oktober 2008
Conclusions • Spectacular case of around-the-world transport of smoke from 2006 Australian forest fires • Passing cold front + heat from the fire caused pyroconvective lofting of plume to tropopause region • CALIOP retrieves 11-15 km plume altitude • OMI O2-O2 sensitive to high aerosol plume • TM4 simulations observed lifecycle of plume best for: • Injection at ~10 km • Soluble tracer ISTP 2009 - 22 Oktober 2008
Questions? ISTP 2009 - 22 Oktober 2008