CCSD1Z00000100000052CCSD1R00000300000032 DELIMETER=EOF; TYPE=CCSD1F000001; CCSD1C00000400000013 ADI=NURSIS01; CCSD1R00000300000032 DELIMETER=EOF; TYPE=CCSD1D000002; ISAMS LEVEL2 DATA STRUCTURE in UARS STANDARD DOCUMENTATION FORMAT WHOLE DATA SET ============== DATA_SET_NAME: ISAMS_Level2_Data DATA_SOURCE: Satellite/Instrument = UARS/ISAMS UARS = Upper Atmosphere Research Satellite ISAMS = Improved Stratospheric And Mesospheric Sounder SCIENTIFIC_CONTACT: Prof. Frederic W. Taylor Department of Atmospheric, Oceanic and Planetary Physics University of Oxford, Clarendon Laboratory, Parks Rd, Oxford, OX1 3PU, England Phone: Oxford (0865) 272902 E-Mail: UK.AC.OX.ATM.ISAMS::TAYLOR SOURCE_CHARACTERISTICS: The specific UARS mission objectives are to study: 1. Energy input and loss in the upper atmosphere 2. Global photochemistry of the upper atmosphere 3. Dynamics of the upper atmosphere 4. The coupling among these processes, and 5. the coupling between the upper and lower atmosphere. There are 10 instruments on board, 9 devoted to the mission objectives plus 1 instrument of opportunity. Energy Input Measurements: SOLSTICE (Solar-Stellar Irradiance Comparison Experiment) SUSIM (Solar Ultraviolet Spectral Irradiance Monitor) PEM (Particle Environment Monitor) Species and Temperature Measurements: CLAES (Cryogenic Limb Array Etalon Spectrometer) ISAMS (Improved Stratospheric and Mesospheric Sounder) MLS (Microwave Limb Sounder) Wind Measurements: HALOE (Halogen Occultation Experiment) HRDI (High Resolution Doppler Imager) WINDII (Wind Imaging Interferometer) Instrument of Opportunity: ACRIM II (Active Cavity Radiometer Irradiance Monitor) See NASA/GSFC (1987) for a detailed desciption of the UARS mission. The UARS satellite is in an orbit inclined at 57 degrees (?TBD) to the equator, and which precesses 5 degrees longitude per day relative to the sun. Thus, for one day's data, local solar time around each orbit is an approximately constant function of latitude (differing by 12 hours for ascending and descending nodes) but over a period of 72 days the entire diurnal cycle is sampled at each latitude. Thermal stability requires that one side of the satellite (+Y) is never illuminated by the sun. To maintain this situation in an orbit that precesses relative to the sun (i.e. not sun-synchronous), the satellite has to be yawed through 180 degrees approximately every 36 days. ISAMS is a limb sounder, which, at the satellite altitude of 600km (?TBD), places the tangent point at 23 degrees from the orbital track. When the satellite flies in the +X direction (defined as forwards), viewing to the (usual) anti-sun side (+Y) gives coverage from 80N to 34S. Conversely, when the satellite yaws to fly in the -X direction (backwards), the coverage viewing to +Y is from 34N to 80S. ISAMS also has the ability, when the sun-satellite geometry is favourable, to view to the -Y side for parts of orbits, increasing the potential coverage to 80N-80S for either satellite flight direction. Spectral selection is achieved by pressure-modulator cells (PMCs) (Taylor, 1983) whose pressures, therefore transmission characteristics, may be altered in flight. The various observing geometries, plus the ability to program the scan pattern and PMC pressures, lead to a large number of operating modes for ISAMS, which may be characterised by some combination of: (1) PMC Cell Pressure in each of the 8 Cells (2) Anti-Sun/Sun side viewing (+/- Y side of spacecraft) (3) Satellite Direction (+/- X direction of motion) (4) Day/Night at tangent point (5) Ascending/Descending node (6) Limb Scan program Whether the tangent point is illuminated or not does not affect the operation of the ISAMS instrument, but it is convenient to add it to this list. INVESTIGATION_OBJECTIVES: To determine the thermal structure of the atmosphere and its fluctuations in space and time (e.g. with season), to investigate the photochemistry of the nitrogen-containing species in the stratosphere, and to study the water-vapour budget of the upper atmosphere. INSTRUMENT_ATTRIBUTES: The ISAMS instrument is an infrared radiometer that observes thermal emission from the Earth's limb. Measurements are in the 4 to 17 micron range using gas correlation spectroscopy and solid-state detectors cooled to 80 degrees Kelvin by closed cycle refrigerators. Observations are made on either side of the spacecraft (although on the -Y side only when the satellite is shielded from the sun by the earth), approximately normal to the direction of flight (there is a small azimuth scan to introduce a component of the satellite velocity vector to cancel Doppler shifts due to the earth's rotation). ISAMS has a total of 32 detector elements. The signal processing electronics extracts 2 radiance measurements (Wide-Band and Pressure Modulated) from each detector every Instrument Measurement Period (IMP=2.048 secs), giving a total of 64 measurements per IMP. The detectors are grouped into 4-element arrays at the end of each of 8 optical paths. Each path passes through a different pressure modulator cell. 2 of these paths (#3 and #7), associated with the two CO2 modulators, also contain a filter wheel, enabling selection from one of 4 different spectral regions during any IMP. Thus there are a total of 14 Spectral channels, which, multiplied by the 2 Signal channels (WB and PM), gives a total of 28 radiance channels of which 16 may be sampled each IMP. Each detector element is rectangular with a nominal width:height ratio of 7:1, giving a field of view (FOV) of angular dimensions 0.35 deg x 0.05 deg, corresponding to approximately 16.6 km x 2.36 km at the tangent point. The 4 elements within an array are vertically displaced by 0.10 degrees, so that the pattern of the FOVs projected on to the atmosphere forms 4 horizontal slits with the spaces in between equal to the height of each strip. The 8 detector arrays are arranged in 2 groups of 4 with coincident FOVs for the 4 detector elements in each group. Group A (associated with PMCs #0-3) are positioned so that the lowest detector element is centred 0.05 deg above the scan mirror boresight, while for Group B (PMCs #4-7), the centre of the highest element is 0.05 deg below the boresight. Thus in any IMP, ISAMS views the atmosphere through 8 rectangular slits, centred at +0.35, +0.25, ... -0.35 deg. relative to the boresight, spanning a vertical range of approximately 35.5 km between the edges of the outermost detectors. To increase the vertical coverage the ISAMS mirror can be scanned in elevation. The nominal scan pattern will be alternate steps of 0.05 degrees and 0.35 degrees per IMP, corresponding to 2 and 14 mirror steps respectively. However at some altitudes the mirror will dwell for more than one IMP to enable measurements to be made at that level in more than one filter wheel position. In 1 EMAF (Engineering MAjor Frame = 65.536 secs = 32 IMPs), there will normally be 2 complete up-down scans. Like the scan pattern, the filter wheels are also programmable. The nominal sequence is to measure Temperature and Pressure during the up-scans (F/W position#0,1, corresponding to the strong and weak parts of the CO2 band), and the other species during the down scans (HNO3 and AEROSOL during the first down-scan of an EMAF, O3 and N2O5 during the second). Table 1. Spectral Channels -------------------------------------------------------------------------------- Detector PM Cell Filter W. Spectral Band Measured Group Cell# gas Position# Channel# (um) Parameter -------------------------------------------------------------------------------- A 0 CO n/a 1 4.6 CO 1 H2O n/a 2 6.8 H2O 2 N2O n/a 3 7.9 N2O 3 CO2 0 4 15.5 Temp/press (High altitude) " " 1 5 16.3 Temp/press (Low altitude) " " 2 6 11.3 HNO3 " " 3 7 10.0 O3 -------------------------------------------------------------------------------- B 4 NO n/a 8 5.3 NO 5 NO2 n/a 9 6.3 NO2 6 CH4 n/a 10 7.4 CH4 7 CO2 0 11 15.5 Temp/press (High altitude) " " 1 12 16.3 Temp/press (Low altitude) " " 2 13 8.1 N2O5 " " 3 14 12.1 Aerosol -------------------------------------------------------------------------------- The hardware is described in Peskett (1985) (Overall design considerations), Gray (1985) and Taylor (1988) (Optics), Werrett and Peskett (1985) (Pressure Modulator and Cooling systems). MEASURED_PARAMETERS: Temporal Range: Data Set extends over mission lifetime (TBD). Each file contains data covering 24 hours. Temporal Resolution: Each location covered approx. every 12 hours. Horizontal Range: 80 deg S to 80 deg N, may be restricted to 34 deg in one hemisphere for certain sun-satellite configurations. Horizontal Resolution: 400 km in line-of-sight direction, 400 km or 200 km along tangent track, depending on measured parameter (see Table 2). 400 km is approx 4 deg lat. Vertical Range: Depends on measured parameter. See Table 2. Vertical Resolution: Generally 0.05 deg elevation increments (approx 2.5 km) Special scan modes will produce profiles at 0.025 deg. Table 2 Measured Parameters -------------------------------------------------------------------------------- Parameter 'SUBTYPE' Pressure Range Altitude Range Units -------------------------------------------------------------------------------- Temperature TEMP * 100 mb - 0.01 mb 15 - 80 km K Pressure PRES * 100 mb - 0.01 mb 15 - 80 km mb Carbon Monoxide CO 100 mb - 0.2 mb 15 - 60 km vmr Water Vapour H2O * 100 mb - 0.05 mb 15 - 70 km " Methane CH4 * 100 mb - 0.05 mb 15 - 70 km " Ozone O3 100 mb - 0.2 mb 15 - 60 km " Nitric Acid HNO3 100 mb - 3 mb 15 - 40 km " DiNitrogen Pentoxide N2O5 50 mb - 0.7 mb 10 - 50 km " Nitrogen Oxide NO 100 mb - 0.2 mb 15 - 60 km " Nitrogen DiOxide NO2 100 mb - 0.7 mb 15 - 50 km " Nitrous Oxide N2O * 100 mb - 0.2 mb 15 - 60 km " -------------------------------------------------------------------------------- *=2 profiles per EMAF, otherwise 1 profile (1 EMAF = 65.536 secs) DATA_SET_QUALITY: [Error estimates for each parameter are tbd.] Each retrieved value in the Level 2 profiles has an associated error, taken from the diagonal of the covariance matrix used in the retrieval, but the off-diagonal elements (which do not form part of the operational Level 2 product) will generally also be significant, i.e. there will be significant vertical correlations in the errors of each profile. The Kalman filtering used in Level 2A processing allows optimal estimates of profiles to be produced at regular intervals from essentially random data input, and also allows profiles to be estimated during (short) periods of no data input. Thus each profile produced is a weighted combination of current, preceding and following measurements. Conversely, any single measurement contributes to more than one profile so that there will be correlations in errors between profiles along the orbit. Systematic errors in the measurements and the retrievals are expected to change with the operating mode of the instrument. DATA_PROCESSING_OVERVIEW: ISAMS Level 2 Processing uses a whole day's Level 1 Data as input, extended by 15 minutes into adjacent days to help initialise the Kalman fitlers. The end products are profiles of Temperature, Pressure, Radiances (all Level 2A) and Constituent volume mixing ratios (2B). A separate radiance file is produced for each channel, defined by the combination of pressure-modulator cell, spectral filter (PMCs#3,7 only), and signal (Wide Band or Pressure-Modulated). Processing consists of three programs run in sequence: Program Input Output ------- ----- ------ LV2TEM Level 1 data Level 2A Data (Temperature and Pressure profiles) LV2RAD Level 1 data Level 2A Data (Radiance profiles) LV2CON Level 2A data Level 2B Data (Constituent vmr profiles) Level 1 data contains radiances measured each IMP. These can be regarded as short profiles (4 detector elements per radiance channel) randomly distributed in altitude (according to the scan pattern) and irregularly spaced in time (interrupted by calibration sequences or filter switching, for example). Level 2A processing uses a Kalman filter on the Level 1 data to produce regularly spaced profiles of the required length at the required output times. LV2TEM has an optional ability to write tangent point pressure information into the Level 1 data, which may be used by LV2RAD (also optionally) to grid the radiances. This is why LV2TEM is run before LV2RAD. Level 2B processing (LV2CON) uses Level 2A data as input and performs independent retrievals (as opposed to Kalman filtering) at output times determined by the coincidence of the Level 2A input profiles. Where the retrieval of one product is significantly affected by contamination from a previously retrieved product, the latter (2B data) may also be used as input to the retrieval of the former. This dictates the order in which retrievals are performed. In extreme cases of mutual contamination (eg N2O and CH4), the facility exists to perform a joint retrieval, producing 2 separate Level 2B files simultaneously. All Level 2 programs are table-driven, the driver tables being defined as 'Calibration' files in the UARS data-processing scheme. The Level 2 files contain profiles which are sequential in time, but grouped into data modes, each data mode being defined by the period during which all the 'relevant' instrument mode parameters remain constant and well defined. For Level 2A products, the selection of relevant parameters, and hence how the day's data is subdivided into modes, is via the Driver Tables. For Level 2B products, the data modes in the output files are defined by the data modes in the Level 2 input files: a mode-change in any input file will create a mode change in the output file. The selection (via the Level 2A Driver Tables) of which modes are relevant to which products may influenced by several possibilities: (1) Since the Kalman filtering in Level 2A is confined within each mode (rather than running through the whole day and back), if there is a sharp discontinuity in the filtered profiles associated with a particular instrument mode change this can be used to prevent filtering across the discontinuity. Changes between +/-Y viewing tracks are an obvious example (i.e. data modes depend upon flip mirror position). (2) If it is known that the systematic errors change with any particular instrument mode parameter, this may be selected as relevant to force the output profiles to be grouped in different modes. For example, although the PMC#1 radiances might not change significantly with changes in the PMC pressure, the error patterns of the H2O retrieval will be significantly affected. Selection of the PMC#1 pressure setting as a relevant mode in the gridding of radiances from PMC#1 will lead to a mode structure that is maintained in the H2O retrieval output. (3) If it is known that subsequent processing will require profiles separated into different instrument modes, the relevant parameters can be used to divide the profiles into the required modes at the Level 2 product stage. For example, if Level 3B gridding is to be performed on ascending and descending profiles separately, it makes sense to use this instrument mode parameter to subdivide the data at the Level 2 stage. For data processing, it is convenient to compress all the relevant information on the instrument mode on into a single I*4 integer, ID = 'abcdefghij', written into each mode header (see under Mode_ID), where each digit is defined in Table 3. Table 3 Level 2 Mode Identification ___________________________________________________________________________ | | | | |Digit| Description | Values (0=undefined) | |_____|_________________________________|_________________________________| | | | | | abc | Scan/Filter program# | 001-100 | | d | Ascending/Descending node | 1=northgoing, 2=southgoing | | e | Day/Night at Tangent point | 1=day, 2=night | | f | Satellite Direction | 1=forwards(+X) 2=backwards(-X) | | g | Flip Mirror View | 1=antisun (+Y), 2=sunside (-Y) | | h | PMCh Press. Range (see Table 4) | 1-9 | | i | PMCi " " " " " | 1-9 | | j | PMCj " " " " " | 1-9 | |_____|_________________________________|_________________________________| Since only 3 out of the 8 PMCs can be defined in this format, the PMCs described by digits 'hij' in the ID have to be defined according to Level 2 product (the others being considered never relevant to the production of this data). See Table 4. Table 4. Allocation of PMC#s to digits 'hij' in Mode ID Code ________________________________ | | | | | | SUBTYPE | PMCh | PMCi | PMCj | |_________|______|______|______| | | | | | | TEMP | #3 | #7 | n/a | | PRES | #3 | #7 | n/a | | pfsRAD | #p | n/a | n/a | | O3 | #3 | n/a | n/a | | H2O | #1 | n/a | n/a | | HNO3 | #3 | n/a | n/a | | CH4 | #6 | #2 | #1 | | N2O | #2 | #6 | #1 | | CO | #0 | #3 | n/a | | NO | #4 | n/a | n/a | | NO2 | #5 | #1 | n/a | | N2O5 | #7 | #1 | #2 | |_________|______|______|______| 'pfs' refers to combination of PMC# (0:7), Filter# (0:3) and signal type (W/P, 'W' for Wide-Band, 'P' for Pressure Modulated) for each radiance file, e.g. '32WRAD' refers to the Wide-Band radiance profiles from PMC#3 with Filter#2. Thus, a mode identification code of '0031021820' in Methane (CH4) data would indicate the following: (1) Scan Program 003 (=abc) was being used (2) The tangent point was northgoing (d=1), (3) No distinction was made between day/night in the processing (e=0), (4) UARS was travelling in the -X direction (f=2), (5) The Flip Mirror was viewing to the +Y side (g=1), and, specifically to CH4 files, (6) PMC#6 was operating at setting#8 (=h), (7) PMC#2 was operating at setting#2 (=i), (8) the setting of PMC#1 was not used to determine the data modes (j=0). A similar code is also attached to individual profiles (see under 'Profile_ID') to allow subsequent regrouping of the data according to different criteria (e.g. for Level 3 processing). The encoding format is the same except that an attempt is made to define the instrument state at all times, not just when they are used to define the Level 2 data modes. Using the above example, each CH4 Profile_ID would be the same as the Mode_ID except that digits 'e' and 'j' would be set to +ve integers rather than '0' and these digits might vary from one profile to another within the same mode. DATA_USAGE: ISAMS Level 2 data consists of estimates of atmospheric profiles on the Measurement Grid. The Measurement Grid is defined as the set of paths corresponding to 0.025 degree intervals in elevation angle (or approx. 1.2km altitude intervals at the tangent point). Level 2 radiance profiles represent the radiance viewed along each of these paths while the temperature, pressure and constituent profiles represent the atmospheric quantities at the tangent point altitudes of each of these paths. The set of tangent points themselves lie on a curve rather than a straight line with a significant horizontal displacement towards the satellite with increasing altitude (approx 2.5km horizontally for 1km vertically). Because of the difficulties of using curved profiles, the Level 2 profiles are defined to lie on a vertical line (i.e. constant latitude/longitude) at the same altitudes as the tangent points rather than at the tangent points themselves. The distinction only becomes significant when considering horizontal gradients in the plane of the profile and the line-of-sight. Each profile has a reference level, generally chosen to be the measurement grid path with tangent point altitude closest to 50km (as predicted by the UARS attitude control system). The profile is located (in lat,lon) by this point, and various other scalar quantities associated with the profile also relate to this point. The measurement grid spacing (0.025 degrees) matches both the scan mirror step-size and the nominal spacing of the detector arrays (Field-of-View (FOV) centres are distributed at +/- 0.05, 0.15, 0.25 and 0.35 degrees about the boresight). Thus, in an ideal system, the measurement grid would remain fixed relative to the satellite and the boresight and all radiance measurements would lie on grid points. Even so, the grid would 'float' in altitude relative to the earth's surface due to satellite roll and the earth's oblateness. Because the mirror scan mechanism is imperfect, successive boresight movements will not be exact multiples of 0.025 degrees, so the measurement grid is defined by the current boresight position rather than relative to the spacecraft. Given the finite detector FOVs and misalignments, the measurements themselves do not correspond to delta-function FOVs at the grid points, but one of the purposes of LV2RAD is to correct for this and estimate the delta-function FOV profiles at the nominal locations. The indexing of the measurement grid is determined by the nominal scan motor steps. Thus if the mirror is instructed to move to step#n (where n=0:251), level n of the measurement grid is defined to correspond to the resulting boresight direction. The mirror position telemetry is more accurate than the motor mechanism, so that level n will generally correspond to slightly different angles relative to the satellite each time. The nominal FOV centres extend up to +/- 0.35 degrees (= +/-14 * 0.025deg) relative to the boresight, so the measurement grid covers the range -14:265 rather than 0:251 to allow for locating radiances when the boresight is at either end of the scan range. In normal operation, the mirror will step in increments of 0.05 degrees, so the profile surfaces will correspond to alternate measurement grid levels, which projects to a vertical resolution of approx. 2.3 km in the atmosphere. The separation of Level 2 data into modes has been described under Data Processing. While profiles may safely be combined (e.g. gridded) from within any single data mode, or from data modes representing the same instrument operating mode (e.g. successive orbits when the flip-mirror is viewing to the same side), systematic differences may occur between profiles from data modes representing different instrument modes (e.g. flip-mirror viewing to different sides). One obvious example is if the pressure of one of the PMC cells is changed: this changes the retrieval weighting functions, and therefore the relative influences of the a priori (climatology) and the measurements in the retrieved product. To distinguish whether data modes within a file correspond to the same instrument mode, the user may inspect the relevant components of the header records for each data mode, or may use the single Mode_ID variable. Using the Reference point altitude, geocentric distance and elevation angle associated with each profile, it is possible to reconstruct the altitudes of the measurement grid using simple trigonometry. In its exact form, Gr cos r = Gi cos i where Gr and Gi are the geocentric distances of the reference point and required point respectively, and r and i are the elevation angles relative to the satellite horizontal. For most purposes it is sufficiently accurate to use a more convenient approximation: Gi = Gr + Gr b ( tan(r) - b/2 ) where b = (i-r) expressed in radians. Hence (Gi-Gr) gives the altitudes relative to the reference altitude. It should be noted that the absolute altitude scale is only as accurate as the UARS Attitude Control System (ACS) data allows. The profiles retrieved on the measurement grid represent the data with as little vertical or horizontal interpolation as possible, and therefore form the best data for comparison with in situ measurements. Because the measurement grid is not tied to altitude other than via the ACS altitude, the pressure values of the measurement grid will also be required for most purposes. In normal processing the pressure profiles will be colocated with other Level 2 profiles so that a conversion can be readily performed. It is expected that only the Temperature and Constituent profiles will be passed on to Level 3 processing, although the Pressure profiles will be used to perform the necessary interpolation on to the standard UARS pressure surfaces that form the vertical coordinate of Level 3 products. All Level 2 products, including the radiance profiles, will be archived. Rodgers (1990) gives the general theory on retrieval errors, and the [tbd] ISAMS error analysis gives specific examples. Two specific warnings are given here: (1) The 'error SD' associated with each level 2 profile value is taken from the square root of the diagonal elements of the associated covariance matrix. Vertical correlations between profile values, represented by the off-diagonal terms, will generally be significant. (2) The retrieval method used represents an optimal combination of measurements and a priori information (i.e. climatology). This should be borne in mind when comparing the retrievals with climatology. An approximate indication of the contribution of climatology towards the solution may be obtained from the relative size of the 'error' associated with the retrieved profile compared to the 'error' (i.e. uncertainty) in the climatological data. DATA_ORGANISATION: All ISAMS Level 2 data is held in files with the same format. Radiance, Temperature and Pressure files are Level 2A products, while Constituent Volume Mixing Ratio files are denoted Level 2B. Each Level 2 file contains data organised into one or more 'Modes', each Mode comprising one or more Profiles. FILE_CLASS_RELATIONSHIPS: There is only one file class (i.e. format) for all ISAMS level 2 files. LIT_REFERENCES: Gray, P.F. (1985) Design and performance of the optical system for ISAMS. Proceedings Vol 589 of Instrumentation for Optical Remote Sensing from Space, Cannes, France, 27-29 November 1985 (Seeley, J.S, Lear, J.W., Monfils, A., and Russak, S.L. eds). Published by SPIE, Bellingham, Wash., USA. NASA/GSFC (1987) UARS Project Data Book. Published by GE (Astro Space Division). Peskett, G.D. (1985) Design of the Improved Stratospheric and Mesospheric Sounder (ISAMS) on the Upper Atmosphere Research Satellite (UARS). Proceedings Vol 589 of Instrumentation for Optical Remote Sensing from Space, Cannes, France, 27-29 November 1985 (Seeley, J.S, Lear, J.W., Monfils, A., and Russak, S.L. eds). Published by SPIE, Bellingham, Wash., USA. Rodgers, C.D. (1990) Characterization and Error Analysis of Profiles Retrieved from Remote Sounding Measurements. J.Geophys.Res., Vol 95, pp.5587-5595 Taylor, F.W. (1983) Pressure Modulator Radiometry. In "Spectrometric Techniques", ed. G. Vanasse. Vol 3, pp.137-197. Taylor, F.W., Scaddan, R.J. and Callard, L. (1988) Improved Stratospheric and Mesospheric Sounder. Optical Engineering, Vol 810, pp.81-90 Werrett, S.T., and Peskett, G.D., (1985) Pressure modulators, closed cycle coolers, and the detector cooling system in ISAMS. Proceedings Vol 589 of Instrumentation for Optical Remote Sensing from Space, Cannes, France, 27-29 November 1985 (Seeley, J.S, Lear, J.W., Monfils, A., and Russak, S.L. eds). Published by SPIE, Bellingham, Wash., USA. FILE CLASS ========== FILE_CLASS_NAME: ISAMS_Level2_Data RECORD_TYPE_NAMES: SFDU_Label, File_Header_Record, Mode_Header_Record_A, Mode_Header_Record_B, Data_Record ALGORITHMS: tbd FILE_CLASS_SYNTAX: No. Records in the file = 2 + 2M + P M = Value (No_Modes_in_File) P = Value (No_Profiles_in_File) List of Records in file: #1: SFDU_Label #2: File_Header_Record #2m+1: Mode_Header_Record_A for Mode #m (m=1 to M) #2m+2: Mode_Header_Record_B for Mode #m #2+2M+p: Data_Record for Profile #p (p=1 to P) FILE_CLASS_FIELD_RELATIONSHIPS: The File Header Record, which is always Record#2 and of fixed length, must be read first to establish values of No_Modes_in_File and No_Profiles_in_File. This establishes the ordering of subsequent Mode Header Records and Data Records. This Record also contains information on the maximum buffer size required to input subsequent Mode Header/Data records (Max_Record_Length) and maximum array size required to accommodate a single profile (Max_No_Surfaces). FILE_CLASS_MISC: The following values are used as 'fill' codes to indicate bad or missing data: Representation Abbreviation Fill_Code Value VI4 BADI4 '80000000'X (=-2147483648) VI2 BADI2 '8000'X (=-32768) VI1 BADI1 '80'X (=-128) VR4 INVALID_REAL_NUMBER '8000'X (not representable) 1A BADCH '#' RECORD ====== 1. SFDU_Label ------------- RECORD_NAME: SFDU_Label RECORD_STRUCTURE: Fixed Length RECORD_LENGTH: 40 Bytes RECORD_FIELD_NAMES: Tz_Field, Lz_Field, Ti_Field, Li_Field RECORD_SYNTAX: 4 Fields #1: Tz_Field #2: Lz_Field #3: Ti_Field #4: Li_Field FIELDS ====== 1.1 Tz_Field ------------ FIELD_NAME: Tz_Field FIELD_MNEMONIC: TZFLD FIELD_SYNTAX: ASCII Character*12 String FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: SFDU Type (Tz) Field. Constant Value = 'CCSD1Z000001' FIELD_REPRESENTATION: 12A FIELD_DISPLAY_FORMAT: A12 1.2 Lz_Field ------------ FIELD_NAME: Lz_Field FIELD_MNEMONIC: LZFLD FIELD_SYNTAX: ASCII Character*8 String FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: SFDU Length (Lz) Field. Value=(length of file - 20bytes) FIELD_REPRESENTATION: 8A FIELD_DISPLAY_FORMAT: A8 1.3 Ti_Field ------------ FIELD_NAME: Ti_Field FIELD_MNEMONIC: TIFLD FIELD_SYNTAX: ASCII Character*12 String FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: SFDU Type (Ti) Field. Constant value = 'NURS1I00IS00' FIELD_REPRESENTATION: 12A FIELD_DISPLAY_FORMAT: A12 1.4 Li_Field ------------ FIELD_NAME: Li_Field FIELD_MNEMONIC: LIFLD FIELD_SYNTAX: ASCII Character*8 String FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: SFDU Length (Li) Field. Value = value (Lz_Field) - 20 FIELD_REPRESENTATION: 8A FIELD_DISPLAY_FORMAT: A8 RECORD ====== 2. File_Header_Record --------------------- RECORD_NAME: File_Header_Record RECORD_STRUCTURE: Fixed Length RECORD_LENGTH: 21 Bytes RECORD_FIELD_NAMES: Max_Record_Length, Max_No_Surfaces, Level2_Type, No_Modes_in_File, No_Profiles_in_File, Level2_AB RECORD_SYNTAX: 6 Fields. #1: Max_Record_Length #2: Max_No_Surfaces #3: Level2_Type #4: No_Modes_in_File #5: No_Profiles_in_File #6: Level2_AB FIELDS ====== 2.1 Max_Record_Length --------------------- FIELD_NAME: Max_Record_Length FIELD_MNEMONIC: RLEN FIELD_SYNTAX: Scalar FIELD_UNITS: Bytes FIELD_RESOLUTION: 1 Byte FIELD_RANGE: 134 to 2290 FIELD_DESCRIPTION: Maximum length of any record in file 134 is the length of the longest fixed-length record (Mode_Header_Record_A), while 2290 corresponds to the length of a profile (Data_Record) with the maximum no. of surfaces (280). FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI4 2.2 Max_No_Surfaces ------------------- FIELD_NAME: Max_No_Surfaces FIELD_MNEMONIC: NSURFM FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to 280 FIELD_DESCRIPTION: Maximum number of data surfaces of any profile in file FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI4 2.3 Level2_Type --------------- FIELD_NAME: Level2_Type FIELD_MNEMONIC: TYPE FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 10 only FIELD_DESCRIPTION: The value '10' is the only value that will be used for production files, indicating profiles produced along-the-orbit, and the on Measurement Grid. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I2 FIELD_FILL_CODE: BADI4 2.4 No_Modes_in_File -------------------- FIELD_NAME: No_Modes_in_File FIELD_MNEMONIC: NMODES FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to approx. 1440 FIELD_DESCRIPTION: Number of Modes in the file. This value is required in order to determine the subsequent record structure of the file. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I4 FIELD_FILL_CODE: BADI4 2.5 No_Profiles_in_File ----------------------- FIELD_NAME: No_Profiles_in_File FIELD_MNEMONIC: NPROFS FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to ca. 2880 FIELD_DESCRIPTION: Number of Profiles in file FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI4 2.6 Level2_AB ------------- FIELD_NAME: Level2_AB FIELD_MNEMONIC: AB FIELD_SYNTAX: ASCII Character*1 FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 'A' or 'B' only FIELD_DESCRIPTION: 'A' if level 2A data (i.e. Temperature, Pressure and Radiance Profiles) 'B' if level 2B data (i.e. Constituent vmr Profiles). The distinction between 2A,2B data is not significant. FIELD_REPRESENTATION: 1A FIELD_DISPLAY_FORMAT: A1 FIELD_FILL_CODE: BADCH RECORD ====== 3. Mode_Header_Record_A ----------------------- RECORD_NAME: Mode_Header_Record_A RECORD_STRUCTURE: Fixed Length RECORD_LENGTH: 136 Bytes RECORD_FIELD_NAMES: First_Profile_No, Last_Profile_No, Profile_Record_Length, Subtype, Content, Start_Time, Finish_Time, Processing_Date, Level1_Version_Nos, Level2_Version_Nos RECORD_SYNTAX: 10 Fields. #1: First_Profile_No #2: Last_Profile_No #3: Profile_Record_Length #4: Subtype #5: Content #6: Start_Time #7: Finish_Time #8: Processing_Date #9: Level1_Version_Nos #10: Level2_Version_Nos FIELDS ====== 3.1 First_Profile_No -------------------- FIELD_NAME: First_Profile_No FIELD_MNEMONIC: PROFF FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to No_Profiles_in_File FIELD_DESCRIPTION: No. of first profile in this Mode FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 3.2 Last_Profile_No ------------------- FIELD_NAME: Last_Profile_No FIELD_MNEMONIC: PROFL FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to No_Profiles_in_File FIELD_DESCRIPTION: No. of last profile in this Mode FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 3.3 Profile_Record_Length ------------------------- FIELD_NAME: Profile_Record_Length FIELD_MNEMONIC: LEN FIELD_SYNTAX: Scalar FIELD_UNITS: Bytes FIELD_RESOLUTION: n/a FIELD_RANGE: 62 to 2294 (=1 to 280 profile levels) FIELD_DESCRIPTION: Length of one profile block in bytes FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I4 FIELD_FILL_CODE: BADI4 3.4 Subtype ----------- FIELD_NAME: Subtype FIELD_MNEMONIC: SUBTYP FIELD_SYNTAX: ASCII Character*12 String FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: Restricted to list of standard ISAMS Subtype names. See Table 2: 'Measured Parameters'. FIELD_DESCRIPTION: Subtype, i.e. used to identify measured parameter within this mode. In Production files, all modes will contain data of the same Subtype. Uppercase, padded with trailing spaces. FIELD_REPRESENTATION: 12A FIELD_DISPLAY_FORMAT: A12 FIELD_FILL_CODE: ' ' 3.5 Content ----------- FIELD_NAME: Content FIELD_MNEMONIC: CONTNT FIELD_SYNTAX: ASCII Character*48 String FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: Text containing any additional comments on data. tbd for production files. Uppercase, padded with trailing spaces. FIELD_REPRESENTATION: 48A FIELD_DISPLAY_FORMAT: A48 FIELD_FILL_CODE: ' ' 3.6 Start_Time -------------- FIELD_NAME: Start_Time FIELD_MNEMONIC: START FIELD_SYNTAX: 1-D Array (2) FIELD_UNITS: UARS Date/Time Format (UDTF) FIELD_RESOLUTION: 1 millisec FIELD_RANGE: Instrument lifetime FIELD_DESCRIPTION: Start time of mode, i.e. time of first profile FIELD_REPRESENTATION: 2VI4 FIELD_DISPLAY_FORMAT: I5,I8 FIELD_FILL_CODE: BADI4 3.7 Finish_Time --------------- FIELD_NAME: Finish_Time FIELD_MNEMONIC: FINISH FIELD_SYNTAX: 1-D Array (2) FIELD_UNITS: UARS Date/Time Format (UDTF) FIELD_RESOLUTION: 1 millisec FIELD_RANGE: Instrument lifetime FIELD_DESCRIPTION: End time of mode, i.e. time of last profile FIELD_REPRESENTATION: 2VI4 FIELD_DISPLAY_FORMAT: I5,I8 FIELD_FILL_CODE: BADI4 3.8 Processing_Date ------------------- FIELD_NAME: Processing_Date FIELD_MNEMONIC: PROCD FIELD_SYNTAX: Scalar FIELD_UNITS: UARS Date Format FIELD_RESOLUTION: 1 Day FIELD_RANGE: Launch date onwards FIELD_DESCRIPTION: Processing date, (day+(year-1900)*1000) FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI4 3.9 Level1_Version_Nos ---------------------- FIELD_NAME: Level1_Version_Nos FIELD_MNEMONIC: VERSN1 FIELD_SYNTAX: 1-D Array (6) FIELD_UNITS: UARS Date Format FIELD_RESOLUTION: n/a FIELD_RANGE: 89001 to current date FIELD_DESCRIPTION: Level 1 processing program dates FIELD_REPRESENTATION: 6VI4 FIELD_DISPLAY_FORMAT: 6I5 FIELD_FILL_CODE: BADI4 3.10 Level2_Version_Nos ---------------------- FIELD_NAME: Level2_Version_Nos FIELD_MNEMONIC: VERSN2 FIELD_SYNTAX: 1-D Array (6) FIELD_UNITS: UARS Date Format FIELD_RESOLUTION: 1 day FIELD_RANGE: 89001 to current date FIELD_DESCRIPTION: Level 2 processing Program & Driver Table version dates: VERSN2 (1) Date of LV2TEM program VERSN2 (2) Date of LV2RAD program VERSN2 (3) Date of LV2CON program VERSN2 (4) Date of LV2TEM driver table VERSN2 (5) Date of LV2RAD driver table VERSN2 (6) Date of LV2CON driver Table FIELD_REPRESENTATION: 6VI4 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI4 RECORD ====== 4. Mode_Header_Record_B ----------------------- RECORD_NAME: Mode_Header_Record_B RECORD_STRUCTURE: Variable Length RECORD_LENGTH: 64 + 5 * Value (No_Contaminants) + 2 * Value (No_Surfaces) Bytes RECORD_FIELD_NAMES: No_Surfaces, Instrument_Status, Filter_Start_EMAF_No, Filter_Stop_EMAF_No, Mean_PMC_Pressures, PMC_Pressure_Codes, Scan_Program_ID, Mode_ID, View_Direction, LR_View_Direction, Satellite_Direction Spacecraft_Status, No_Contaminants, Contaminants_List, Surfaces_List RECORD_SYNTAX: 15 Fields. #1: No_Surfaces #2: Instrument_Status #3: Filter_Start_EMAF_No #4: Filter_Stop_EMAF_No #5: Mean_PMC_Pressures #6: PMC_Pressure_Codes #7: Scan_Program_ID #8: Mode_ID #9: View_Direction #10: LR_View_Direction #11: Satellite_Direction #12: Spacecraft_Status #13: No_Contaminants #14: Contaminants_List #15: Surfaces_List FIELDS ====== 4.1 No_Surfaces --------------- FIELD_NAME: No_Surfaces FIELD_MNEMONIC: NSURF FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to value (Max_No_Surfaces) FIELD_DESCRIPTION: Number of profile levels FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I3 FIELD_FILL_CODE: BADI2 4.2 Instrument_Status --------------------- FIELD_NAME: Instrument_Status FIELD_MNEMONIC: INSTAT FIELD_SYNTAX: 1-D Array (10) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: tbd FIELD_DESCRIPTION: ISAMS Instrument Status. TBD. FIELD_REPRESENTATION: 10VI1 FIELD_DISPLAY_FORMAT: tbd FIELD_FILL_CODE: BADI1 4.3 Filter_Start_EMAF_No ------------------------ FIELD_NAME: Filter_Start_EMAF_No FIELD_MNEMONIC: NEMSTA FIELD_SYNTAX: 1-D Array (3) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to ca. 1440 FIELD_DESCRIPTION: Starting EMAF# for each of 3 passes of Kalman filter used in Level 2A processing of this mode. Pass#1 is the initialisation pass, which may be omitted. FIELD_REPRESENTATION: 3VI2 FIELD_DISPLAY_FORMAT: 3I4 FIELD_FILL_CODE: BADI2 4.4 Filter_Stop_EMAF_No ----------------------- FIELD_NAME: Filter_Stop_EMAF_No FIELD_MNEMONIC: NEMSTA FIELD_SYNTAX: 1-D Array (3) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to ca. 1440 FIELD_DESCRIPTION: Finishing EMAF# for each of 3 passes of Kalman filter used in Level 2A processing of this mode. Pass#1 is the initialisation pass, which may be omitted. FIELD_REPRESENTATION: 3VI2 FIELD_DISPLAY_FORMAT: 3I4 FIELD_FILL_CODE: BADI2 4.5 Mean_PMC_Pressures ---------------------- FIELD_NAME: Mean_PMC_Pressures FIELD_MNEMONIC: PMCPAV FIELD_SYNTAX: 1-D Array (0:7) FIELD_UNITS: mb/300 FIELD_RESOLUTION: 0.0033 mb FIELD_RANGE: 150 (0.5 mb) to 12000 (40 mb) FIELD_DESCRIPTION: Mean pressures for all PMCs FIELD_REPRESENTATION: 8VI2 FIELD_DISPLAY_FORMAT: 8I5 FIELD_FILL_CODE: BADI2 4.6 PMC_Pressure_Codes ---------------------- FIELD_NAME: PMC_Pressure_Codes FIELD_MNEMONIC: PMCPID FIELD_SYNTAX: 1-D Array (0:7) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 0 to 9 FIELD_DESCRIPTION: PMC operating pressure codes (1-9) (0 if not set) Each code The allocation of pressure ranges to each code are tbd. FIELD_REPRESENTATION: 8VI1 FIELD_DISPLAY_FORMAT: 8I1 FIELD_FILL_CODE: BADI1 4.7 Scan_Program_ID ------------------- FIELD_NAME: Scan_Program_ID FIELD_MNEMONIC: PRCIDM FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: >0 FIELD_DESCRIPTION: Scan program ID for this mode. 5 least-significant bits refer to version#, remainder is program#. FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 4.8 Mode_ID ----------- FIELD_NAME: Mode_ID FIELD_MNEMONIC: MODEID FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: Identification code for mode (see under Data Usage). This is a single number combining all relevant mode-identification parameters. Data from modes with the same Mode_ID value represent instrument modes which are identical with respect to data retrievals. See 'Data Processing Overview' for encoding details. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I11 FIELD_FILL_CODE: BADI4 4.9 View_Direction ------------------ FIELD_NAME: View_Direction FIELD_MNEMONIC: VIEW FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1,2 or 3 FIELD_DESCRIPTION: View Direction: 1=anti-sun (+Y) only, 2=sunside (-Y) only 3 = sun/anti-sun combined FIELD_REPRESENTATION: VI1 FIELD_DISPLAY_FORMAT: I1 FIELD_FILL_CODE: BADI1 4.10 LR_View_Direction ---------------------- FIELD_NAME: LR_View_Direction FIELD_MNEMONIC: VIEWLR FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1,2, or 3 FIELD_DESCRIPTION: Left/Right view direction relative to satellite velocity vector: 1=to left, 2=to right, 3=combined left & right FIELD_REPRESENTATION: VI1 FIELD_DISPLAY_FORMAT: I1 FIELD_FILL_CODE: BADI1 4.11 Satellite_Direction ------------------------ FIELD_NAME: Satellite_Direction FIELD_MNEMONIC: DIRECT FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1,2,3,5,6,7,9,10,11 FIELD_DESCRIPTION: Satellite direction and orientation: 1=forwards and northwards, 2=(f,s), 3=(f,n+s), 5=(b,n), 6=(b,s), 7=(b,n+s), 9=(f+b,n), 10=(f+b,s), 11=(f+b,n+s) FIELD_REPRESENTATION: VI1 FIELD_DISPLAY_FORMAT: I2 FIELD_FILL_CODE: BADI1 4.12 Spacecraft_Status ---------------------- FIELD_NAME: Spacecraft_Status FIELD_MNEMONIC: SCSTAT FIELD_SYNTAX: 1-D Array (6) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: tbd FIELD_DESCRIPTION: Spacecraft Status this day. TBD FIELD_REPRESENTATION: 6VI1 FIELD_DISPLAY_FORMAT: tbd FIELD_FILL_CODE: BADI1 4.13 No_Contaminants -------------------- FIELD_NAME: No_Contaminants FIELD_MNEMONIC: NCNTAM FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to 5 FIELD_DESCRIPTION: No. of absorbers/contaminants used (max 5) FIELD_REPRESENTATION: VI1 FIELD_DISPLAY_FORMAT: I1 FIELD_FILL_CODE: BADI1 4.14 Contaminants_List ---------------------- FIELD_NAME: Contaminants_List FIELD_MNEMONIC: CONTAM FIELD_SYNTAX: ASCII Character*5 String 1-D Array (n), where n is value (No_Contaminants) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: List of contaminant/absorber gases used and sources CONTAM (1:3) contains the ISAMS C*3 codes for species: 'CO_', 'CO2', 'H2O', 'CH4', 'F11'(=CFCl3), 'F12'(=CFCl2), 'O3_', 'HN3'(=HNO3), 'N25'(=N2O5), 'NO2', 'NO_', 'O2_', 'SAX'(=Stratospheric Aerosol). CONTAM (4:4) is blank ' ' CONTAM (5:5) contains the ISAMS source-identifier code: 'C' for climatology, 'R' for previous retrieval FIELD_REPRESENTATION: n(A5) FIELD_DISPLAY_FORMAT: nA5 FIELD_FILL_CODE: BADCH 4.15 Surfaces_List ------------------ FIELD_NAME: Surfaces_List FIELD_MNEMONIC: SURFS FIELD_SYNTAX: 1-D Array (n), where n is value (No_Surfaces) FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: -280 to 280 FIELD_DESCRIPTION: List of surface indices (i.e. Measurement grid levels) relative to the offset surface index supplied for each profile (see 'Offset_Surface'). All profiles within the mode are defined on the same set of relative surfaces, but with an arbitrary offset that may vary from profile to profile. FIELD_REPRESENTATION: NSURF*VI2 FIELD_DISPLAY_FORMAT: nI4 FIELD_FILL_CODE: BADI2 RECORD ====== 5. Data_Record -------------- RECORD_NAME: Data_Record RECORD_STRUCTURE: Variable Length RECORD_LENGTH: 56 + 8*NSURF bytes RECORD_FIELD_NAMES: Mode_Number, Profile_ID, Profile_Time, Local_Solar_Time, Reference_Geocentric_Height, Reference_Altitude, Latitude, Longitude, Line_of_Sight_Direction, Solar_Zenith_Angle, Sun_Line_of_Sight_Angle, PMC_Pressure, Offset_Surface, Reference_Level_Index, Reference_Pressure, Reference_Pressure_Error, Reference_Elevation_Angle, Data_Profile, Error_Profile RECORD_SYNTAX: 19 Fields #1: Mode_Number #2: Profile_ID #3: Profile_Time #4: Local_Solar_Time #5: Reference_Geocentric_Height #6: Reference_Altitude #7: Latitude #8: Longitude #9: Line_of_Sight_Direction #10: Solar_Zenith_Angle #11: Sun_Line_of_Sight_Angle #12: PMC_Pressure #13: Offset_Surface #14: Reference_Level_Index #15: Reference_Pressure #16: Reference_Pressure_Error #17: Reference_Elevation_Angle #18: Data_Profile #19: Error_Profile FIELDS ====== 5.1 Mode_Number --------------- FIELD_NAME: Mode_Number FIELD_MNEMONIC: MODE FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: 1 to value (No_Modes) FIELD_DESCRIPTION: Mode Header Number which applies, i.e. which pair of mode header records at the start of the file describe the data mode to which this profile belongs. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I4 FIELD_FILL_CODE: BADI4 5.2 Profile_ID -------------- FIELD_NAME: Profile_ID FIELD_MNEMONIC: PROFID FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: n/a FIELD_DESCRIPTION: Profile Identification Code. Combines the instrument mode parameters into a single variable representing the status of the instrument at the profile time. Encoding is described under 'Data Processing Overview'. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I11 FIELD_FILL_CODE: BADI4 5.3 Profile_Time ---------------- FIELD_NAME: Profile_Time FIELD_MNEMONIC: DATTIM FIELD_SYNTAX: 1-D Array (2) FIELD_UNITS: UARS Date/Time Format (UDTF) FIELD_RESOLUTION: 1 millisec FIELD_RANGE: Instrument lifetime FIELD_DESCRIPTION: UARS Date/time attached to profile. FIELD_REPRESENTATION: 2VI4 FIELD_DISPLAY_FORMAT: I5,I8 FIELD_FILL_CODE: BADI4 5.4 Local_Solar_Time -------------------- FIELD_NAME: Local_Solar_Time FIELD_MNEMONIC: LST FIELD_SYNTAX: Scalar FIELD_UNITS: millisecs FIELD_RESOLUTION: 1 millisec FIELD_RANGE: 0 to 86399999 FIELD_DESCRIPTION: Local solar time at reference tangent point. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I8 FIELD_FILL_CODE: BADI4 5.5 Reference_Geocentric_Height ------------------------------- FIELD_NAME: Reference_Geocentric_Height FIELD_MNEMONIC: GCH FIELD_SYNTAX: Scalar FIELD_UNITS: metres FIELD_RESOLUTION: 1 metre FIELD_RANGE: 6405000 to 6430000 FIELD_DESCRIPTION: Geocentric Distance of reference tangent point i.e. distance to earth centre. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I7 FIELD_FILL_CODE: BADI4 5.6 Reference_Geodetic_Altitude ------------------------------- FIELD_NAME: Reference_Geodetic_Altitude FIELD_MNEMONIC: ALT FIELD_SYNTAX: Scalar FIELD_UNITS: metres FIELD_RESOLUTION: 1 metre FIELD_RANGE: 49000 to 51000 (nominal) FIELD_DESCRIPTION: Geodetic Altitude of reference tangent point i.e. shortest distance to earth surface. FIELD_REPRESENTATION: VI4 FIELD_DISPLAY_FORMAT: I6 FIELD_FILL_CODE: BADI4 5.7 Latitude ------------ FIELD_NAME: Latitude FIELD_MNEMONIC: LAT FIELD_SYNTAX: Scalar FIELD_UNITS: degrees N/100 FIELD_RESOLUTION: 0.01 degrees FIELD_RANGE: -9000 to 9000 FIELD_DESCRIPTION: Latitude of reference tangent point. FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 5.8 Longitude ------------- FIELD_NAME: Longitude FIELD_MNEMONIC: LONG FIELD_SYNTAX: Scalar FIELD_UNITS: degrees E/100 FIELD_RESOLUTION: 0.01 degrees FIELD_RANGE: -18000 to +18000 FIELD_DESCRIPTION: Longitude of reference tangent point. FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I6 FIELD_FILL_CODE: BADI2 5.9 Line_of_Sight_Direction --------------------------- FIELD_NAME: Line_of_Sight_Direction FIELD_MNEMONIC: LOS FIELD_SYNTAX: Scalar FIELD_UNITS: degrees/100 FIELD_RESOLUTION: 0.01 degrees FIELD_RANGE: -18000 to +18000 FIELD_DESCRIPTION: Angle between northward meridian and Line-of-sight direction at the reference tangent point (+ve values indicate LOS direction to east, i.e. satellite to west). FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I6 FIELD_FILL_CODE: BADI2 5.10 Solar_Zenith_Angle ----------------------- FIELD_NAME: Solar_Zenith_Angle FIELD_MNEMONIC: ZENANG FIELD_SYNTAX: Scalar FIELD_UNITS: degrees/100 FIELD_RESOLUTION: 0.01 degrees FIELD_RANGE: 0 to +18000 FIELD_DESCRIPTION: Solar zenith angle at reference tangent point FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 5.11 Sun_Line_of_Sight_Angle ---------------------------- FIELD_NAME: Sun_Line_of_Sight_Angle FIELD_MNEMONIC: SUNANG FIELD_SYNTAX: Scalar FIELD_UNITS: degrees/100 FIELD_RESOLUTION: 0.01 degrees FIELD_RANGE: 0 to +18000 FIELD_DESCRIPTION: Angle between Ref.Lev tangent pt. view direction and sun FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 5.12 PMC_Pressure ----------------- FIELD_NAME: PMC_Pressure FIELD_MNEMONIC: PMCP FIELD_SYNTAX: Scalar FIELD_UNITS: mb/300 FIELD_RESOLUTION: 0.0033 mb FIELD_RANGE: 150 (0.5 mb) to 12000 (40 mb) FIELD_DESCRIPTION: Pressure of primary PMC used in retrieval FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I5 FIELD_FILL_CODE: BADI2 5.13 Offset_Surface ------------------- FIELD_NAME: Offset_Surface FIELD_MNEMONIC: SFCOFF FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: -14 to 265 (approx.) FIELD_DESCRIPTION: Offset Surface No. to be added to SURFS list, ie profile value DAT2(s) is on Surface No. SFCOFF + SURFS(s). FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I3 FIELD_FILL_CODE: BADI2 5.14 Reference_Level_Index -------------------------- FIELD_NAME: Reference_Level_Index FIELD_MNEMONIC: REFMGI FIELD_SYNTAX: Scalar FIELD_UNITS: n/a FIELD_RESOLUTION: n/a FIELD_RANGE: -14 to 265 FIELD_DESCRIPTION: Measurement Grid Index of reference tangent point, i.e. which of the 280 measurement grid tangent points is being used as the reference tangent point for this profile. FIELD_REPRESENTATION: VI2 FIELD_DISPLAY_FORMAT: I3 FIELD_FILL_CODE: BADI2 5.15 Reference_Pressure ----------------------- FIELD_NAME: Reference_Pressure FIELD_MNEMONIC: REFPRE FIELD_SYNTAX: Scalar FIELD_UNITS: mb FIELD_RESOLUTION: n/a FIELD_RANGE: 0.5 to 1.0 mb (approx) FIELD_DESCRIPTION: Pressure of reference tangent point FIELD_REPRESENTATION: VR4 FIELD_DISPLAY_FORMAT: E12.5 FIELD_FILL_CODE: INVALID_REAL_NUMBER 5.16 Reference_Pressure_Error ----------------------------- FIELD_NAME: Reference_Pressure_Error FIELD_MNEMONIC: REFPQL FIELD_SYNTAX: Scalar FIELD_UNITS: mb FIELD_RESOLUTION: n/a FIELD_RANGE: >0 FIELD_DESCRIPTION: Rms accuracy of reference pressure FIELD_REPRESENTATION: VR4 FIELD_DISPLAY_FORMAT: E12.5 FIELD_FILL_CODE: INVALID_REAL_NUMBER 5.17 Reference_Level_Angle -------------------------- FIELD_NAME: Reference_Level_Angle FIELD_MNEMONIC: REFANG FIELD_SYNTAX: Scalar FIELD_UNITS: degrees elevation FIELD_RESOLUTION: 0.0002 degrees FIELD_RANGE: -28.5 to -18.5 FIELD_DESCRIPTION: Elevation scan angle at reference tangent point FIELD_REPRESENTATION: VR4 FIELD_DISPLAY_FORMAT: F8.4 FIELD_FILL_CODE: INVALID_REAL_NUMBER 5.18 Data_Profile ----------------- FIELD_NAME: Data_Profile FIELD_MNEMONIC: DAT2 FIELD_SYNTAX: 1-D Array (n), where n is value (No_Surfaces) FIELD_UNITS: depends on data Subtype. See under Measured Parameters FIELD_RESOLUTION: n/a FIELD_RANGE: depends on data Subtype. See under Measured Parameters FIELD_DESCRIPTION: Retrieved profile FIELD_REPRESENTATION: nVR4 FIELD_DISPLAY_FORMAT: nE12.5 FIELD_FILL_CODE: INVALID_REAL_NUMBER 5.19 Error_Profile ------------------ FIELD_NAME: Error_Profile FIELD_MNEMONIC: QUAL FIELD_SYNTAX: 1-D Array (n), where n is value (No_Surfaces) FIELD_UNITS: same as DAT2 FIELD_RESOLUTION: n/a FIELD_RANGE: >0 FIELD_DESCRIPTION: Rms accuracy of profile values FIELD_REPRESENTATION: nVR4 FIELD_DISPLAY_FORMAT: nE12.5 FIELD_FILL_CODE: INVALID_REAL_NUMBER