Detection of upper level SO2 via the GOES Sounder

1
Detection of upper level SO2 via the GOES
Sounder

• Fred Prata1, Anthony Schreiner2,
• Gary Ellrod3 and Timothy Schmit4
• 1CSIRO Atmospheric Research, Australia
• 2Cooperative Institute for Meteorological
  Satellite Studies (CIMSS)
  
• University of Wisconsin-Madison
• Madison, WI 53706, U.S.A.
• 3NOAA/NESDIS, Office of Research and
  Applications
  
• Camp Springs, Maryland
• 4NOAA/NESDIS, Office of Research and
  Applications
  
• Madison, WI 53706, U.S.A.

2
The GOES Sounder
3
The GOES Sounder
4
SO2 from GOES

• Infrared channel near 7.3 µm SO2 absorption
  (channel 11)
  
• Reference channel (channel 9)
• Upper-level SO2 only (3 km)
• Example Montserrat

5
SO2 Retrieval from Sounder Data

• Absorption measurement. GOES channel 11
  brightness temperatures are colder than expected,
  because of the presence of SO2.
  
• Reference channel. A second channel is used to
  eliminate background effects. The O3 channel was
  used (channel 9).
  
• Brightness temperature difference (DBT). The DBT
  is related to transmittance and then to absorber
  amount through radiative transfer modelling.

6
GOES-12
SO2 retrieval using the ozone channel as reference
7
Montserrat
TOMS
GOES
HYSPLIT
AIRS
JULY 13, 2002
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Conclusions

• It appears that the GOES sounder is capable of
  detecting Upper Troposphere Lower Stratosphere
  SO2.
  
• Unprecedented temporal resolution heralds new
  possibilities for monitoring SO2 and ash.
  
• Changes to the ABI will permit purposeful SO2
  detection using the 7.3 µm channel.
  
• More work is required to validate the SO2
  retrievals and to find the optimum reference
  channels.