MOPITT

MOPITT Campaign

2 March 1998 - 6 March 1998

Lead Scientist: Jinxue Wang

Observatory: SGP (Southern Great Plains)

It is important to have confidence in the correlative data and associated data processing algorithms before they can be used to validate the MOPITT data products. It is also useful to test the intercomparison techniques which are to be used in post-launch MOPITT data validation. The Pre-launch MOPITT Validation Exercise (Pre-MOVE) was a validation campaign at the Southern Great Plain (SGP) Cloud and Radiation Testbed (CART) of the Department of Energy Atmospheric Radiation Measurement (DOE/ARM) program in Lamont, Oklahoma from March 2 to March 6 of 1998. The reasons for conducting Pre-MOVE at the CART site included the following: (1) It is a heavily instrumented site resulting in good characterization of surface and the atmosphere column; (2) We can make use of CART high resolution solar absorption interferometer (SORTI & ASTI), thermal emission interferometer (AERI), lidars, and radiosonde data. This saves us from deploying similar instruments ourselves for Pre-MOVE; (3) There is excellent logistic support at the site. The primary goals of Pre-MOVE included: (1) Conduct a test of the MOPITT Airborne Test Radiometer (MATR) and associated data processing algorithm by comparing the retrieved CO profiles from MATR observations with aircraft in-situ CO profile measurement by the NOAA/CMDL flask system. (2) Validate the retrieval algorithm, which derives column CO from ground-based thermal emission interferometer (AERI) measurement, to be used by McMillan et al. for post-launch MOPITT data validation. The retrieved CO column will be compared with that derived from aircraft in-situ CO profile measurement by the NOAA/CMDL flask system and other techniques. (3) Validate the retrieval algorithm, which derives column CO and possibly tropospheric CO profile from ground-based solar absorption interferometer (SORTI) measurement to be used by Frank Murcray et al. and Pougatchev et al. for MOPITT validation. The retrieved CO column will be compared with that derived from aircraft in-situ CO profile measurement by the NOAA/CMDL flask system and other techniques. (4) Validate the retrieval algorithm, which derives column CO and possibly tropospheric CO profile from ground-based solar absorption interferometer (SORTI) measurement, to be used by Murcray et al. and Pougatchev et al. for MOPITT validation. The retrieved CO column will be compared with that derived from aircraft in-situ CO profile measurement by the NOAA/CMDL flask system and other techniques. Two independent algorithms, one by Murcray et al. and one by Pougatchev et al., will be used and compared in the retrieval of columns of CO and CH4 and possibly CO profiles from high resolution solar absorption measurements by Fourier transform interferometers. This will give us more confidence in the use of the large number of observations by Fourier transform interferometers around the world. The involvement of both groups give us the desired global coverage by ground-based Fourier transform interferometers and grating spectrometers. (5) Validate the retrieval algorithm, which derives total CO column from ground-based grating spectrometer measurement, to be used by Yurganov and Tolton for MOPITT data validation. Similar grating spectrometers have been used in Russia, China, and possibly other countries for many years to monitor total CO column. The validation of those kind of measurements as part of the Pre-MOVE will give us confidence to use similar measurements in Russia and China for MOPITT data validation. (6) Intercompare all the instruments and techniques to be used in post-launch MOPITT data validation. It is expected that those intercomparisons will lead to the refinement of all the associated data processing algorithms and intercomparison protocols.