AIRS-Suite Radiosonde Matchup Interface Specification The AIRS-Suite Radiosonde matchup file (AIRX2MAT) interface is the special case of the AIRS-Suite Truth Matchup Interface below where Truth_File_Type is "PREPQC.ADPUPA". Each matchup file will be in HDF-EOS swath format. It can contain up to eight swaths as follows: - L1B_AIRS_Science - L1B_VIS_Science - L1B_AMSU - L1B_HSB - L2_Standard_atmospheric&surface_product - L2_Support_atmospheric&surface_product - L2_Standard_cloud-cleared_radiance_product - Matchup_Info Any number of these swaths may be missing, but if present all have the same size on their primary dimension (GeoTrack) and there is a one-to-one correspondence between items at the same GeoTrack index in each swath. The dimension "GeoTrack" has a slightly different meaning for swaths in the matchup file than for swaths in standard AIRS PGE products. For those files it corresponds to the number of instrument scans that took place during the period when this data was being collected. For this file it means the total number of AIRS-suite profiles ("golfballs") contained in the file. Because this file is a collection of profiles for which truth matches happened to be found, no assumptions should be made about the geographic relations between profiles. Except for Matchup_info each swath follows the interface specification in the AIRS Processing Files Description document for the corresponding swath file with the following changes: - All "Attributes" (which are once per file in the standard swath files) become fields with dimensions GeoTrack + listed "Extra Dimensions". - For "big spot" swaths (L1B_AMSU, all L2): - Dimension GeoXTrack is removed - Fields which were "Along-Track" have the same dimensions (GeoTrack + listed "Extra Dimensions") - Fields which were "Full Swath" have the same dimensions except that the second dimension (GeoXTrack) is removed. (Dimensions are now GeoTrack + listed "Extra Dimensions") - For "small spot" swaths (L1B_HSB, L1B_AIRS_Science, L1B_VIS_Science): - Dimension GeoXTrack is replaced by SubTrack3x3 & SubXTrack3x3 (both always set to 3) - Fields which were "Along-Track" have one extra dimension inserted after GeoTrack, "SubTrack3x3". (Dimensions are now GeoTrack,SubTrack3x3 + listed "Extra Dimensions") - Fields which were "Full Swath" have the same dimensions except that the second dimension (GeoXTrack) is replaced by two dimensions, "SubTrack3x3,SubXTrack3x3". (Dimensions are now GeoTrack,SubTrack3x3,SubXTrack3x3 + listed "Extra Dimensions") - There are two additional 32-bit integer fields dimensioned "GeoTrack". - "start_scan_line_number" contains the scan line number (1-based) of the first footprint in its original granule. - "start_footprint_number" contains the footprint number (1-based) of the first footprint in its original granule. - Geolocation Fields have only the dimension "GeoTrack". For "small spot" swaths this corresponds to the center footprint. These "small spot" swaths have additional 64-bit floating-point "Full Swath" fields named "footprint_latitude", "footprint_longitude", and "footprint_taitime" which contain the per-footprint geolocation information. - The fields listed below are removed because they give granule-level information that is not useful in a matchup context (When '*' is the last character then it matches all fields with that start of a name): "num_*", "processing_level", "instrument", "AutomaticQAFlag", "QAPercentProcessData", "QAPercentMissingData", "QAPercentSpecialData", "QAPercentBadData", "node_type", "start_year", "start_month", "start_day", "start_hour", "start_minute", "start_sec", "start_Latitude", "start_Longitude", "start_Time", "end_Latitude", "end_Longitude", "end_Time", "nadirTAI", "stat_*", "QA_*", "granules_present", "gain_fit_dev", "rad_stats", "rad_unc_stats", "rad_scan_stats", "offset_unc_stats", "offset_stats", "limit_offsets", "offset_fit_dev", "input_vis_det_temp", "input_phot_counts", "input_scene_counts", "input_space_counts", "input_spec_counts", "input_bb_counts", "input_bb_temp", "input_spec_temp", "input_ir_det_temp", "input_grating_temp", "input_opt_bench_temp", "input_scan_mirror_temp", "offset_fit_dev", "nen_stat", "polar_stat", "popcorn_up_stat", "popcorn_down_stat", "limit_*", (Note: the rest of the list added Nov 8, 2000) "offset_begin", "offset_end", "offset_err", "gain", "offset", "nominal_freq", "spectral_freq_prev", "DCR_*", "popcorn_report", "effective_bb_temp", "nadir_contrast", "spec_*", "gain_*", "bulb_failed", "K21", "K32", "K31", "K_factors_applied", "gamma_*", "track_err", "xtrack_err", "align_*", "cal_coef_*", "IF_offset_*", "bandwidth", "center_freq" The Matchup_Info swath will have these swath attributes: Name Type Explanation Truth_File_Type String of This item contains the type of truth file 8-bit being matched. It must always exactly characters match one of these valids: PREPQC.ADPUPA ADP upper air radiosonde records from PREPQC. This is the only valid value under operational circumstances at the GDAAC. ARM/CART ARM/CART site. (TBD) Buoy records. NONE No truth file. OTHER Other. Truth_File_Name String of This item contains the filename of the file being 8-bit matched. When "Truth_File_Type=" "NONE" or characters "OTHER" this field can contain the identity of the originator of this request or information about the purpose of this experiment. Maximum 255 characters. Truth_File_UR String of This is the Universal Reference (UR) for the 8-bit file named in "Truth_File_Name=". It is characters ignored when "Truth_File_Type= NONE". Truth_File_Version String of This is the TBD versioning information about 8-bit the truth file. It is ignored when characters "Truth_File_Type= NONE". Modification_History String Free-format text (up to 80 characters) giving of 8-bit the history of modifying this file, for characters instance might contain, "hand-modified by EMM to increase time window for ocean records". Suggested value is "N/A" for no modification. Matchup_Info contains space for up to 5 matches for each value of GeoTrack. This reflects the possibility that more than one truth record can be within the specified time & distance window of a truth observation. If there are fewer than 5 matches, the remaining match structures will be marked invalid by having all characters of the truth_type field NUL (zero). The HDF-EOS Matchup_Info swath will contain the following dimensions: Name Value Explanation GeoTrack # of profiles The total number of AIRS-suite profiles ("golfballs") contained in the file. (Same as for all other swaths.) MaxMatch 5 Maximum number of truth profiles matched to (TBD) one AIRS golfball. SubTrack3x3 3 Number of along-track spots per profile for small-spot swaths (L1B AIRS, VIS, HSB) SubXTrack3x3 3 Number of across-track spots per profile for small-spot swaths (L1B AIRS, VIS, HSB) MaxString 80 Maximum number of characters in a string. The Matchup_Info Swath will have geolocation fields Latitude, Longitude, Time with dimensions "GeoTrack,MaxMatch". For each match the following fields will be present. In the HDF-EOS Matchup_Info swath, each field below will have dimensions "GeoTrack,MaxMatch" before the specified "Extra Dimensions". Name Type Extra Dimensions Explanation Elevation 32-bit None The elevation of the surface at floating- the location of the observation, point in meters above the reference ellipsoid. -9999.0 for unknown. Surface_Pressure None The surface pressure in mb at 32-bit Elevation. -9999.0 for unknown. floating- point Sea_Level_Surface_Pressure The surface pressure in mb at 32-bit None the reference ellipsoid. floating- -9999.0 for unknown. point delta_sec 32-bit None Time difference (in seconds) integer between the taking of the truth data and the AIRS-suite observations. Positive for AIRS data taken first. -99999999 for unknown. dist_amsu 32-bit None Distance (km) between location of floating- AMSU-A observations & of truth. point Truth_Type 8-bit MaxString (=80) String uniquely identifying truth profile characters type. Only valid value is "PREPQC.ADPUPA" (string) for data produced from PREPQC data in the operational RaObs matchup PGE at the GDAAC. Other values will be designated for other types of truth. All characers NUL (0) denote no matchup present at this MaxMatch index. Profile_Id 8-bit MaxString (=80) String uniquely identifying truth profile characters within the truth file. For PREPQC data (string) this will be the SID (TBD). Profile_Index 32-bit Index uniquely identifying truth profile integer within the truth file. For PREPQC data this will be the SQN (TBD). Quality_Indicator MaxString (=80) Up to 80-character string indicating 8-bit the quality of a given truth record. characters Definitions are: (string) PREPQC.ADPUPA Number of levels at which this profile has valid temperatures. ARM/CART TBD NONE User-defined (Note: the following ASCII graphics require a fixed-width font) Figure 1: Conceptual Layout of Matchup File Geo- Track +---------------------------------------------------------------------------------+ | | | +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ | | | AMSU | | HSB | | AIRS | | VIS | | L2 | | L2 | | L2 | | MATCH | | | | L1B | | L1B | | L1B | | L1B | | STD | | SUP | | CC | | swath | | | | swath | | swath | | swath | | swath | | swath | | swath | | swath | | | | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | 0 | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | | || || || | | || || | | || || | | || || || || || || || || || | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | | | | | | | | | | | | | | | | | | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | 1 | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | | || || || | | || || | | || || | | || || || || || || || || || | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | | | | | | | | | | | | | | | | | | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | 2 | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | | || || || | | || || | | || || | | || || || || || || || || || | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... | | ... | | ... | | ... | | ... | | ... | | ... | | ... | | ... | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | N | || || || | | || || | | || || | | || || || || || || || || || | | || || |+-+-+-+| |+-+-+-+| |+-+-+-+| || || || || || || || || | | || || || | | || || | | || || | | || || || || || || || || || | | |+-----+| |+-+-+-+| |+-+-+-+| |+-+-+-+| |+-----+| |+-----+| |+-----+| |+-----+| | | | | | | | | | | | | | | | | | | | | +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ | | | +---------------------------------------------------------------------------------+ Figure 2: Closeup of AIRS L1B Swath Geo- Track +-----------------------------------------------------+ | AIRS L1B Swath | | | | +-----------+-----------+-----------+ --- | | | Info | | | ^ | | | for | | | | | | | one | | | | | | | AIRS | | | | | | | footprint | | | | | | +-----------+-----------+-----------+ | | | | | | | SubTrack3x3 | | | | | | = 3 | 1 | | | | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | v | | +-----------+-----------+-----------+ --- | | |<--------SubXTrack3x3 = 3--------->| | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | 2 | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | ... | ... | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | N | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | +-----------+-----------+-----------+ | | | | | +-----------------------------------------------------+