Australian forest fires

1
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
2

• 14 December 2006 severe forest fires in SE
  Australia release aerosol boomerang
• Pyroconvective lofting facilitated long range
  transport
• Determine the plumes altitude OMI O2-O2,
  CALIOP, TM4
• Conclusions

3
Meteorological situation 14 Dec 2006
Weathermap of 14 December 2006, 1600 LT Cold
front passing over fire location
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The Victoria blowup 14 Dec 2006 Observed by MODIS
Courtesy M. Fromm
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OMI O2-O2 cloud algorithm
Absorption scattering

• O2-O2 collision complex _at_477nm, pressure
  dependent
• Measures air column above cloud
• Linedepth ? cloud height
• Background ? cloud fraction

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Altitude information O2-O2
Source region
NZ
OMI RGB 15 Dec

• Adjacent clouds 1-5km
• Scene pressure of plume itself yields higher
  altitudes

7
Evolution of the plume
Orbit 12924
Orbit 12953
TM4 tropopause
TM4 tropopause
21 Dec
19 Dec
Cloudless
High Clouds
CALIPSO footprint
8
TM4 simulation Passive tracer Water
soluble Injection height 248 hPa (10km)
reproduces OMI AAI observations
CTMs dont incorporate latent heat from fires,
emissions released at ground level
9
TM4 profiles for various injection heights
Injection height 248 hPa gives best agreement
with CALIOP observations
10
Injection height
High resolution 1-D plume rise model to simulate
lofting of the plume by pyro-convection Input Met
eorological conditions at fire location on 14 Dec
2006 Fire front intensity, latent heat
Courtesy Maria Val Martin
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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
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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

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Questions?