CCSD1Z00000100000052 CCSD1R00000300000032 DELIMTER=EOF; TYPE=CCSD1F000001; CCSD1C00000400000013 ADI=NURSCL00; CCSD1R00000300000032 DELIMTER=EOF; TYPE=CCSD1D000002; UPPER ATMOSPHERE RESEARCH SATELLITE CRYOGENIC LIMB ARRAY ETALON SPECTROMETER STANDARD FORMAT DATA UNITS WHOLE DATA SET DOCUMENT September 1997 G.A. Ely Lockheed Palo Alto Research Laboratory Lockheed Missiles and Space Company Palo Alto, California INTRODUCTION ------------ This document complies with the UARS' mission requirement that all UARS experiment contractors submit a comprehensive description of their final level 2 and level 3 data products to UARS::CONTROL. These descriptions will be used by group whose mandate is to archive all UARS data for use by the general community. This group will replace the original organization; the National Space Science Data Center. This document describes the data produced by the CLAES processing software run on the UARS Central Data Handling Facility for the version shown below. DOCUMENTATION HIERARCHY ----------------------- The documentation will follow the guidelines established by David Gell (Univ. of Mich.) and Richard Murphy (Southwest Research, Inc.) in their publication, "Data Documentation Standard for the Upper Atmosphere Research Satellite." This standard meets the recommendations of the Consultive Committee for Space Data Systems for Standard Formatted Data Units (SFDUs). The hierarchy begins with a description of the data set as a whole. There follows a description of data products within the whole as they evolve at the various levels (referred to as file classes) of processing. All file class data are further classified into one or more stand alone groupings which are referred to as records. The individual elements of these records, known as fields, can be found in the supporting SFDU documents for level 2 and level 3AT and level 3AL. Standard Format Data Unit Document List: NURS1I00CL00 FileClass: Whole Data Set (*) NURS1I00CL01 FileClass: Level 3AT Data NURS1I00CL02 FileClass: Level 3AL Data NURS1I00CL03 FileClass: Level 2 Data NURS1I00CL04 FileClass: Data Set Change History [(*) Current Document] Whole Data Set: --------------- Keyword Value Description ------- ----------------- DataSetName : CLAES DataSource : Lockheed Palo Alto Research Laboratory's Cryogenic Limb Array Etalon Spectrometer (CLAES); one of the instrument experiments on board the Upper Atmosphere Research Satellite (UARS) ScientificContacts: Dr. Aidan E. Roche CLAES Principal Investigator Work: (415) 424-2109 VAXmail address: CLAES::ROCHE EMail address: roche@CLAES.space.lockheed.com Dr. John B. Kumer CLAES Principal Scientist Work: (415) 424-2327 VAXmail address: CLAES::KUMER EMail address: kumer@CLAES.space.lockheed.com Mr. Gary A. Ely CLAES RAC System Manager/Delivery Representative Work: (415) 424-2361 VAXmail address: CLAES::ELY EMail address: ely@CLAES.space.lockheed.com The mailing address for those listed above is: Lockheed Palo Alto Research Laboratory B/255, O/91-20 3251 Hanover Street Palo Alto, CA 94304 SourceCharacteristics: The UARS satellite, a platform for ten scientific instruments, was injected from the space shuttle into a 600 kilometer orbit having an inclination of 57 degrees on 12 September 1991. The satellite was designed to have a life of 36 months. The orbit definition permits the 90° limb-viewing instruments to take measurements to ±80° latitude providing coverage for more than 98% of the earth's surface. Data acquired by the various sensor instruments are telemetered to earth receiving stations using NASA's multimission modular spacecraft (MMS) communications and data handling module. Limb scanning and solar viewing to a primary system pointing accuracy of 36 arc sec will be provided by the MMS attitude control system (ACS). The length of valid data acquisition time for the CLAES scientific instrument was ~19 months; from 1 October 1991 to 5 May 1993. InvestigationObjectives: The UARS satellite will gain definitive information about the chang- ing conditions in the stratosphere and mesosphere, including the de- pletion of ozone. It is anticipated that this information will greatly enhance current understanding of the mechanisms that control the upper atmosphere's structure and variability, its response to manmade and natural perturbations, and the nature of the role these play in climatic change. The primary objective of the CLAES exper- iment is to measure the altitude profiles of temperature and a series of minor and trace species important to stratospheric ozone layer photochemistry and radiative structure. For full description of the CLAES instrument and specie measurements, please refer to "The Cryogenic Limb Array Etalon Spectrometer (CLAES) on UARS: Experiment Description and Performance", A.E. Roche, et al., Journal of Geophysical Research, Volume 98, number D6, pages 10,763-10,775, June 20, 1993. InstrumentAttributes: The CLAES instrument collects radiation through its 6-inch aperture Mersene telescope which is adjusted to observe the proper range of atmospheric altitudes through the use of its motorized limb acquisi- tion and adjustment mirror (LAAM). The LAAM will also be driven in concert with the earth oblateness updated from the UARS observatory computer. The high off-axis reflection and low scatter infrared telescope optics allow observations within just 0.3 degree above the hard earth. Spectroscopy is performed by tilt scanning one of the four solid etalons between one or more of the nine blocking filters. The Fabry_Perot spectrometer is augmented by a 72 hertz chopper and two refractive lens groups which direct focused infrared radiation to the focal plane array (FPA). The FPA is made up of a linear array of 20 detectors operated between 5.27 and 12.82 micrometers and three additional detectors, used to measure HCL, which are operated at 3.52 micrometers. All the detectors are made of gallium-doped silicon. The HCL detectors are six times longer vertically than those of the main array resulting in a coarser altitude resolution for this species. A solid cryogen cooler keeps the FPA below 16 degrees K, the spec- trometer below 30 degrees K, and the telescope below 150 degrees K. The CLAES electronics subsystem is a microcomputer based instrument controller. Two such subsystems, of which only one is operational at any given time, provide functional block redundancy. The micro- computers are RCA 1802s with 16k byte of RAM which can be accessed entirely from the ground via the UARS telemetry link. Commands to the microcomputer from the ground and from the microcomputer to various CLAES instrument components provide the ability to operate autonomously for days in the normal science mode, in calibration mode or in special purpose mission configurations. For a complete description of the design and operation of the CLAES instrument refer to session 7 of Volume 973 of the published papers of the pro- ceedings for the meeting of the International Society for Optical Engineering held August 17-19, 1988 in San Diego, California. This volume is entitled "Cryogenic Optical Systems and Instruments III" and is edited by Ramsey K. Melugin and Warren G. Pierce. MeasuredParameters: The CLAES instrument measures infrared spectral earthlimb emission on the tangent altitude range from 15 to 65 km in 9 spectral regions of width 12 to 4 cm-1 that are located near 2843, 1897, 1605, 1257, 925, 879, 840, 792 and 780 cm-1. The measurements have spectral resolution 0.65 to 0.2 cm-1, altitude resolution 2.5 km, and horizontal resolution ~460 km. Retrieval algorithms applied to these data derive stratospheric altitude profiles of temperature, pressure, O3 (for the 792 cm-1 and the 780 cm-1 blocker filters), H2O, CH4, N2O, NO, NO2, N2O5, HNO3, ClONO2, CFCl3, CF2Cl2, and aerosol extinction coefficient for each spectral region. DataSetQuality: A set of references to appropriate journal articles, presenta- tions and reports that address overall quality considerations including calibration and validation approaches, and the esti- mates of uncertainties are documented in the "UARS Validation Workshop II Report: Temperature and Constituents", October 12-16, 1992; editors: John Gille and William Grose. DataProcessingOverview: The reader is directed to the CLAES Ground Data Processing Software User Guide, version 6.00, 11 October 1995 for a complete description of the processing overview. DataUseage: Anticipated uses of these data are in the fields of understanding unperturbed atmospheric chemistry and dynamics, tracking global change and long term atmospheric trends, predicting atmospheric response to chemical or energetic perturbations, environmental and agricultural planning, weather forecasting, atmospheric energy input and loss studies, and radiation budgets. Estimates of the uncertainties in these data are listed in "CLAES CH4, N2O, and CFC12 (CFCL3) Global Data"; by J.B. Kumer, J.L. Mergenthaler, and A.E. Roche; Geophysical Research Letters, Volume 20, Number 12, pages 1239-1242, June 18, 1993. The data associated with these SFDU's are produced using the CLAES version 6.06 software and carry a data version on the CDHF of version 8. DataOrganization: These data are organized into files containing approximately 24 hours of CLAES data. The data are obtained through the UARS CHDF UCSS data interface routines. There are two sets of data each consisting of 14 files (one per retrieved specie). One set is interpolated to the UARS level 3a pressure grid as a function of time (level 3aT). The other set is interpolated to the UARS level 3a pressure grid as a function of latitude from the level 3aT set (level 3aL). FileClassRelationships: The CLAES level 2 and level 3 file classes are related by the UARS definition. The CLAES level 2 data are the parameters stratospheric altitude profiles of temperature, pressure, O3, H2O, CH4, N2O, NO, NO2, N2O5, HNO3, ClONO2, CFCl3, CF2Cl2, and aerosol extinction coefficient reported at the specific instrument footprint, subject to implementation of the retrieval algorithms. The CLAES level 3 data are these parameters interpolated to a standard UARS grid. LitReferences: The following is a list of CLAES publications as of February 1994: "CLAES CH4, N2O,and CCl2F2 (F12) Global Data", (J.B. Kumer, J.L. Mergenthaler and A.E. Roche, Geophys. Res. Lett., 20, 1239, June 18, 1993). "CLAES Observations of ClONO2 and HNO3 in the Antarctic Stratosphere, between June 15 and September 17 1992", (A.E. Roche, J.L. Mergenthaler and J.B. Kumer, Geophys. Res. Lett., 20, 1223, June 18, 1993). "CLAES South-Looking Aerosol Observations for 1992", (J.L. Mergenthaler, J.B. Kumer, and A.E. Roche, Geophys. Res. Lett., 20, 1295, June 18, 1993). "The Cryogenic Limb Array Etalon Spectrometer (CLAES) on UARS: Experiment Description and Performance", (A.E. Roche, J.B. Kumer, J.L. Mergenthaler, G.A. Ely, W.G. Uplinger, J.F. Potter, T.C. James and L.W. Sterritt, J. Geophys. Res., 98, 10763, June 20, 1993.) "Stratospheric Transport from the Tropics to Middle Latitudes by Planetary-Wave Mixing", (W.J. Randel, J.C. Gille, A.E. Roche, J.B. Kumer, J.W. Waters, E.F. Fishbein and W.A. Lahoz, Nature, 365, 533, Oct. 7, 1993.) "Northern Hemisphere Mid-Stratosphere Vortex Processes Diagnosed from H2O, N2O and Potential Vorticity", (W.A. Lahoz, E.S. Carr, L. Froidevaux, R.S. Harwood, J.B. Kumer, J.L. Mergenthaler, G.E. Peckham, W.G. Read, P.D. Ricaud, A.E. Roche, and J.W. Waters, Geophys. Res. Lett. 20, 2671, Dec. 14, 1993.) Other than the references listed above, the reader is directed to "Selected Papers on The Upper Atmosphere Research Satellite (UARS): Results From the First Year and a Half of Operations" from Geophysical Research Letters; Volume 20, Number 12; published by the American Geophysical Union.