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Atmospheric Chemistry and Dynamics Laboratory (Code 614)

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Colin J. Seftor's Home Page

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Colin J. Seftor, PhD
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  • Ph.D. in Physics, The George Washington University, DC, 1988
  • M.S. in Physics, University of California, Los Angeles, 1981
  • B.S. in Physics, University of California, Los Angeles, 1979

Current Stuff

Ozone hole image for NPP; takes you our web site

I am the task lead of NASA's OMPS Calibration Group. My responsibilities include overseeing all aspects related to the calibration of the OMPS sensors, and the development and maintenance of L1B products.

My duties include:

Supervising (and performing some of) the analytical work performed in support of the calibration team's activities, including:

1) Determining how best to validate and update the calibration from both the nadir and limb sensors of the Ozone Mapping and Profiler Suite (OMPS) instruments that are currently on the SNPP satellite and that will be flown on subsequent JPSS satellites;

2) Assessing and evaluating overall OMPS system performance; and

3) Helping to define the calibration and validation tasks to be performed post-launch for OMPS.

Before leading the calibration group, I was the lead of the OMPS Nadir Science Team task as well as the lead of the OMPS SIPS.

Previous Stuff

NPOESS logo; takes you to IPO's site

I was a member of the System Engineering and Test Integrated Product Team (IPT) for NPOESS. NPOESS was a joint Air Force, NOAA, and NASA program to develop the next generation polar-orbiting weather satellite system. Part of this IPT's job was to develop the calibration/validation component of the NPP/NPOESS system. I concentrated on (but was not limited to) cal/val for OMPS. Now that the NPOESS program has been "blown up," we're back to separate programs for the military (Air Force) and NOAA. The new NOAA program is called the Joint Polar Satellite System, with NASA providing procurement and ground system support for NOAA. It will be composed of the same sensors that were to fly on NPOESS (including OMPS). As mentioned above, OMPS is one of the NPOESS sensors currently flying on Suomi NPP.

OMPS logo; takes you to NASA's NPP Ozone ST web site

I was on the Ball Aerospace team that created and built the OMPS system. I developed the total column ozone retrieval algorithm that was originally used by NOAA for the OMPS nadir mapper operational product. I was also part of the team that defined the sensor performance characteristics for the OMPS sensors so that, when they are used with the OMPS algorithms, the whole system will provide optimized performance. As part of NASA's NPP science team, I am now working on applying NASA's latest algorithm, which I also helped to develop, to OMPS data to so that high performance retrievals can be made available to the scientific community for the continuation of NASA's long term ozone climate data record.

TOMS logo; takes you to OzoneAQ, successor to the TOMS web site

I contributed to the development of Version 7 of NASA's total column ozone retrieval algorithm used by the Total Ozone Mapping Spectrometer (TOMS) sensors. I created simulations and analysis techniques designed to estimate the errors inherent in such algorithms and worked closely with instrument design personnel to help evaluate sensor performance and its effect on algorithm accuracy and precision. I also helped develop, analyze, and validate the Aerosol Index, a product from UV sensors such as TOMS to detect and track UV-absorbing tropospheric aerosols, and I have been involved in retrieving volcanic SO2 and ash amounts from TOMS data. Finally, I helped (a bit) in the development of Version 8 of this algorithm that not only is used with TOMS but also with the Ozone Monitoring Instrument (OMI) onboard EOS-Aura and, now, for NASA's Suomi NPP OMPS reserach data set.

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