Steve,
        Wearing my investigator hat for the WB-57, I had some discussions with the OMI satellite representatives about some of their validation needs during TC-4. One area of interest is the radiation field in and around clouds. This relates to the issue raised at the Science Team meeting by Mark Schoeberl on the satellite ozone measurements above clouds.
        The CAFS instruments will be measuring UV and visible actinic flux. These measurements above, in and below cloud will provide data to determine the multiple scattering of UV that may be effecting the satellite determinations of ozone above clouds. Flight plans that had legs just above cloud deck, slow penetrations through the cloud deck at various depths, and below the cloud deck would be required to quantify the multiple scattering. These might have to be done at a variety of solar zenith angles to parameterize the scattering. These cloud penetrations would also allow for in situ ozone measurements in cloud to look at the discrepancies Mark presented at the Science Team meeting.
        Since we will only have the downwelling CAFS instrument on the DC-8 we will not learn much from measurements on the DC-8. I'll be at the Flight Planning meeting in Boulder next week so we can possibly discuss this further with the larger group.

Cheers,
Rick

Rick Shetter
Director
National Suborbital Education and Research Center
Northern Great Plains Center for People and the Environment
University of North Dakota
Box 9011
Grand Forks, ND 58202-9011
701-330-2126 Mobile
r.shetter@nserc.und.edu

FedEx address:
Rick Shetter
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University of North Dakota
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