{
  "Spase": {
    "xmlns": "http://www.spase-group.org/data/schema",
    "xmlns:xsi": "http://www.w3.org/2001/XMLSchema-instance",
    "xsi:schemaLocation": "http://www.spase-group.org/data/schema http://www.spase-group.org/data/schema/spase-2_6_1.xsd",
    "_Note": "Nodes prefixed with a _ are not valid SPASE, but are included for debugging. Values prefixed with a x_ are not valid SPASE but may considered for addition for completeness.",
    "Version": "2.6.1",
    "_MasterURL": "https://cdaweb.gsfc.nasa.gov/pub/software/cdawlib/0JSONS/icon_l2-1_mighti-a_los-wind-green_00000000_v01.json (from all.xml)",
    "NumericalData": {
      "ResourceID": "spase://NASA/NumericalData/ICON/MIGHTI/L2/A/Green/PT30S",
      "_ResourceID": "Source: https://github.com/rweigel/cdawmeta-spase/blob/main/ResourceID.json",
      "ResourceHeader": {
        "ResourceName": "Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) Sensor A: Line-of-sight Wind Profiles",
        "_ResourceName": "Source: Master/CDFglobalAttributes/Logical_source_description",
        "Description": "ICON explores the boundary between Earth and space - the ionosphere - to understand the physical connection between our world and the immediate space environment around us. Visit 'http://icon.ssl.berkeley.edu' for more details.",
        "_Description": "Source: Master/CDFglobalAttributes/TEXT",
        "Acknowledgement": "This is a data product from the NASA Ionospheric Connection Explorer mission, an Explorer launched at 21:59:45 EDT on October 10, 2019, from Cape Canaveral AFB in the USA. Guidelines for the use of this product are described in the ICON Rules of the Road  (http://icon.ssl.berkeley.edu/Data).  Responsibility for the mission science falls to the Principal Investigator, Dr. Thomas Immel at UC Berkeley:  Immel, T.J., England, S.L., Mende, S.B. et al. Space Sci Rev (2018) 214: 13. https://doi.org/10.1007/s11214-017-0449-2  Responsibility for the validation of the L1 data products falls to the instrument lead investigators/scientists.  * EUV: Dr. Eric Korpela :  https://doi.org/10.1007/s11214-017-0384-2  * FUV: Dr. Harald Frey : https://doi.org/10.1007/s11214-017-0386-0  * MIGHTI: Dr. Christoph Englert : https://doi.org/10.1007/s11214-017-0358-4, and https://doi.org/10.1007/s11214-017-0374-4  * IVM: Dr. Roderick Heelis : https://doi.org/10.1007/s11214-017-0383-3  Responsibility for the validation of the L2 data products falls to those scientists responsible for those products.  * Daytime O and N2 profiles: Dr. Andrew Stephan : https://doi.org/10.1007/s11214-018-0477-6  * Daytime (EUV) O+ profiles: Dr. Andrew Stephan : https://doi.org/10.1007/s11214-017-0385-1  * Nighttime (FUV) O+ profiles: Dr. Farzad Kamalabadi : https://doi.org/10.1007/s11214-018-0502-9  * Neutral Wind profiles: Dr. Jonathan Makela : https://doi.org/10.1007/s11214-017-0359-3  * Neutral Temperature profiles: Dr. Christoph Englert : https://doi.org/10.1007/s11214-017-0434-9  * Ion Velocity Measurements : Dr. Russell Stoneback : https://doi.org/10.1007/s11214-017-0383-3  Responsibility for Level 4 products falls to those scientists responsible for those products.  * Hough Modes : Dr. Chihoko Yamashita :  https://doi.org/10.1007/s11214-017-0401-5  * TIEGCM : Dr. Astrid Maute : https://doi.org/10.1007/s11214-017-0330-3  * SAMI3 : Dr. Joseph Huba : https://doi.org/10.1007/s11214-017-0415-z  Pre-production versions of all above papers are available on the ICON website.  http://icon.ssl.berkeley.edu/Publications  Overall validation of the products is overseen by the ICON Project Scientist, Dr. Scott England.  NASA oversight for all products is provided by the Mission Scientist, Dr. Jeffrey Klenzing.  Users of these data should contact and acknowledge the Principal Investigator Dr. Immel and the party directly responsible for the data product (noted above) and acknowledge NASA funding for the collection of the data used in the research with the following statement :  'ICON is supported by NASA's Explorers Program through contracts NNG12FA45C and NNG12FA42I'.  These data are openly available as described in the ICON Data Management Plan available on the ICON website (http://icon.ssl.berkeley.edu/Data). ",
        "_Acknowledgement": "Source: Master/CDFglobalAttributes/Acknowledgement",
        "_Rights": {
          "Name": "SPDX",
          "Description": "Creative Commons Zero v1.0 Universal",
          "URL": "https://spdx.org/licenses/CC0-1.0.html",
          "SchemeURI": "https://spdx.org/licenses/"
        },
        "InformationURL": [
          {
            "URL": "http://icon.ssl.berkeley.edu/Instruments/MIGHTI",
            "Name": "ICON MIGHTI",
            "Description": "MIGHTI Line-of-sight Wind Profiles (DP 2.1)",
            "_Note": "URL also in all.xml. Using master."
          },
          {
            "Name": "Additional information on ICON",
            "URL": "https://icon.ssl.berkeley.edu/",
            "Description": "ICON spacecraft Homepage.",
            "_Note": "Source: InformationURL.json"
          },
          {
            "Name": "Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI): instrument design and calibration",
            "URL": "https://doi.org/10.1007/s11214-017-0358-4",
            "Description": "Space Science Reviews, 212(1-2), pp.553-584. DOI: 10.1007/s11214-017-0358-4",
            "_Note": "Source: InformationURL.json"
          }
        ]
      },
      "ProviderResourceName": "ICON MIGHTI Line-of-sight Wind Profiles (DP 2.1)",
      "DOI": "https://doi.org/10.48322/07nf-qa27",
      "_DOI": "Source: https://github.com/rweigel/cdawmeta-spase/blob/main/DOI.json",
      "AccessInformation": [
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "CDF"
          ],
          "Style": "Listing",
          "AccessURL": {
            "Name": "HTTPS from SPDF",
            "URL": "https://cdaweb.gsfc.nasa.gov/pub/data/icon/l2/l2-1_mighti-a_los-wind-green",
            "Description": "In CDF via HTTP from CDAWeb",
            "AccessFilenameTemplate": "icon_l2-1_mighti-a_los-wind-green_%Y%m%d_v06r000.nc",
            "AccessDirectoryTemplate": "%Y",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN"
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "CDF"
          ],
          "Style": "Listing",
          "AccessURL": {
            "Name": "FTPS from SPDF",
            "URL": "ftps://cdaweb.gsfc.nasa.gov/pub/data/icon/l2/l2-1_mighti-a_los-wind-green",
            "Description": "In CDF via HTTP from CDAWeb",
            "AccessFilenameTemplate": "icon_l2-1_mighti-a_los-wind-green_%Y%m%d_v06r000.nc",
            "AccessDirectoryTemplate": "%Y",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN"
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "CDF",
            "CSV",
            "GIF",
            "NetCDF",
            "PNG",
            "PS",
            "PDF",
            "XML",
            "x_Script.IDL",
            "x_Script.Python",
            "Text.ASCII",
            "x_WAV"
          ],
          "AccessURL": {
            "Name": "CDAWeb Web Service",
            "URL": "https://cdaweb.gsfc.nasa.gov/WebServices/",
            "Style": "WebService",
            "Description": "Instructions for using web services to access this dataset an other other metadata and options for CDAWeb datasets. The ProductKey here corresponds to the query parameter 'dataset' in the tables at the AccessURL in a dataset-related request can be made.",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN"
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "CDF",
            "GIF",
            "PDF",
            "Text.ASCII",
            "x_WAV"
          ],
          "AccessURL": {
            "Name": "CDAWeb Web Service user interface",
            "URL": "https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?index=sp_phys&dataset=ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Style": "WebService",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Description": "Web service user interface for this product."
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "x_Script.IDL",
            "x_Script.Python"
          ],
          "AccessURL": {
            "Name": "CDAWeb Python Script",
            "URL": "https://cdaweb.gsfc.nasa.gov/WS/cdasr/1/dataviews/sp_phys/datasets/ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN/clientLibraryExample/",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Style": "WebService",
            "Description": "Web service that generates a Python script to access this product."
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/SSCWeb. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "HTML"
          ],
          "AccessURL": {
            "Name": "4D Orbit Viewer",
            "URL": "https://sscweb.gsfc.nasa.gov/4dorbit/?sc=ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Style": "x_Visualization",
            "Description": "Web Service to this product."
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb and the HAPI project. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "CSV",
            "JSON",
            "Binary"
          ],
          "AccessURL": {
            "Name": "CDAWeb HAPI Server",
            "URL": "https://hapi-server.org/servers/#server=CDAWeb&dataset=ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Style": "HAPI",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Description": "Web Service to this product using the HAPI interface."
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb and the HAPI project. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "x_Script.IDL",
            "x_Script.Javascript",
            "x_Script.MATLAB",
            "x_Script.Python",
            "x_Script.Autoplot",
            "x_Script.curl",
            "x_Script.wget"
          ],
          "AccessURL": {
            "Name": "CDAWeb HAPI Script in Multiple Languages",
            "URL": "https://hapi-server.org/servers/#server=CDAWeb&dataset=ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN&return=script",
            "Style": "HAPI",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Description": "Web Service user interface that generates scripts in IDL, Javascript, MATLAB, Python, Autoplot, curl, wget to access this product. See https://hapi-server.org/servers/api for the API."
          }
        },
        {
          "RepositoryID": "spase://SMWG/Repository/NASA/GSFC/SPDF",
          "Availability": "Online",
          "AccessRights": "Open",
          "Acknowledgement": "SPDF/CDAWeb and the HAPI project. Please also acknowledge the data producer: T. J. Immel at UC Berkeley>SSL",
          "Format": [
            "PNG",
            "PDF",
            "SVG"
          ],
          "AccessURL": {
            "Name": "HAPI visualizations",
            "URL": "https://hapi-server.org/plot/?server=https://cdaweb.gsfc.nasa.gov/hapi&dataset=ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN&format=gallery",
            "Style": "x_Visualization",
            "ProductKey": "ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN",
            "Description": "Web Service that generates plots. See https://hapi-server.org/plot/ for the API."
          }
        }
      ],
      "_AccessInformation": "Source: https://github.com/rweigel/cdawmeta-spase/blob/main/AccessInformation.json",
      "TemporalDescription": {
        "TimeSpan": {
          "StartDate": "2019-12-06T00:00:12Z",
          "StopDate": "2022-11-24T23:58:27Z"
        },
        "_TemporalDescription": "Generated from all.xml/@timerange_start and all.xml/@timerange_stop"
      },
      "Keyword": [
        "Ionospheric Connection Explorer (from all.xml/observatory/description/@short)",
        "Michelson Interferometer for Global High-resolution Thermospheric Imaging, Sensor A (from all.xml/instrument/description/@short)",
        "Space Physics (from Master/CDFglobalAttributes/Discipline)",
        "Ionospheric Science (from Master/CDFglobalAttributes/Discipline)",
        "ICON (from Master/CDFglobalAttributes/Source_name)",
        "Ionospheric Connection Explorer (from Master/CDFglobalAttributes/Source_name)",
        "DP21 (from Master/CDFglobalAttributes/Data_type)",
        "Data Product 2.1: Line-of-sight Wind Profiles (from Master/CDFglobalAttributes/Data_type)",
        "MIGHTI-A (from all.xml/instrument/@ID)"
      ],
      "ObservedRegion": [
        "Earth.NearSurface.Atmosphere",
        "Earth.NearSurface.Ionosphere"
      ],
      "_ObservedRegion": "Source: https://github.com/rweigel/cdawmeta-spase/blob/main/ObservedRegion.json",
      "ProcessingLevel": null,
      "_ProcessingLevel": "Processing level is not available in the master file; it should be there instead of, say, https://github.com/rweigel/cdawmeta-spase/blob/main/ProcessingLevel.json",
      "InstrumentID": "spase://SMWG/Instrument/ICON/MIGHTI",
      "MeasurementType": "Dopplergram",
      "Parameter2": [
        {
          "Name": "time_epoch",
          "ParameterKey": "Epoch_cdf",
          "Description": "CATDESC: 'time_inboard'. Notes not in Master CDF: 'The units are the units in CDF files. For other web services, this variable is may be represented as a time string.'",
          "Units": "seconds since 1970-01-01 00:00:00",
          "Support": {
            "Qualifier": "Scalar",
            "SupportQuantity": "Temporal"
          }
        },
        {
          "Name": "Altitude",
          "ParameterKey": "ICON_L21_Altitude",
          "Description": "Master CDF CATDESC: 'WGS84 altitude of each wind sample'. Master CDF VAR_NOTES: 'The altitudes of each point in the wind profile, evaluated using the WGS84 ellipsoid. If the variable Integration_Order=0 (which is the default value), then these altitudes are one half sample above the tangent altitudes of each pixel's line of sight (consistent with the assumption implicit in the inversion that the wind and emission rate are constant within the layer between tangent altitudes). If Integration_Order=1, this variable contains the tangent altitudes.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "km",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Fringe Amplitude",
          "ParameterKey": "ICON_L21_Fringe_Amplitude",
          "Description": "Master CDF CATDESC: 'Fringe amplitude profile'. Master CDF VAR_NOTES: 'An approximate volume emission rate (VER) profile in arbitrary units. Technically this a profile of the amplitude of the fringes, which has a dependence on thermospheric temperature and background emission. Thus, it does not truly represent volume emission rate. However, it is a useful proxy. The units are arbitrary, but an attempt has been made to cross-calibrate MIGHTI-A with MIGHTI-B. In contrast to the wind inversion, which is nonlinear due to the phase extraction step, the amplitude inversion is purely linear. The Level 1 interferogram is analyzed to obtain a single brightness value per zenith angle, and this is inverted with the distance matrix to obtain a value of the amplitude per altitude.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "arb",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Fringe Amplitude Error",
          "ParameterKey": "ICON_L21_Fringe_Amplitude_Error",
          "Description": "Master CDF CATDESC: 'Fringe amplitude error profile'. Master CDF VAR_NOTES: 'The statistical (1-sigma) error in the fringe amplitude. As with the wind, systematic errors are not included, but can arise from sources such as horizontal gradients and inaccurate calibration.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "arb",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Latitude",
          "ParameterKey": "ICON_L21_Latitude",
          "Description": "Master CDF CATDESC: 'WGS84 latitude of each wind sample'. Master CDF VAR_NOTES: 'The latitudes of each point in the wind profile, evaluated using the WGS84 ellipsoid. The latitude only varies by several degrees from the bottom of the profile to the top. It should be noted that while a single latitude value (the tangent latitude) is given for each point, the observation is inherently a horizontal average over many hundreds of kilometers.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "deg",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Line-of-sight Azimuth",
          "ParameterKey": "ICON_L21_Line_of_Sight_Azimuth",
          "Description": "Master CDF CATDESC: 'Azimuth angle of the line of sight at the tangent point. Deg East of North.'. Master CDF VAR_NOTES: 'Consider the vector pointing from the spacecraft to the tangent point (i.e., the line of sight). At the tangent point, this vector is parallel to the ground. This variable contains the azimuth angle of this vector, evaluated at the tangent point. It follows the typical geophysical convention of degrees East of North (North=0, East=90, South=180, West=270). It can vary by a few degrees from the top of the profile to the bottom, so one value is reported per altitude. MIGHTI-A and MIGHTI-B will have values approximately 90 degrees apart.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "deg",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Low-signal correction",
          "ParameterKey": "ICON_L21_Low_Signal_Effect_Correction",
          "Description": "Master CDF CATDESC: 'Correction for low-signal effect'. Master CDF VAR_NOTES: 'This is the correction used for the \"low signal effect\" in the lower-level processing. This correction has already been applied to the data, but is included here for reference. It was taken directly from the Level 1 file but has been converted from rad to m/s. For the red channel, it has also been binned to match the data. It has not been modified by the inversion. The uncertainty of this correction is captured by the Line_of_Sight_Wind_Precision_Low_Signal_Effect variable. See the notes for that variable for more information.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Line-of-sight Wind",
          "ParameterKey": "ICON_L21_Line_of_Sight_Wind",
          "Description": "Master CDF CATDESC: 'Line-of-sight horizontal wind profile. A positive wind is towards MIGHTI.'. Master CDF VAR_NOTES: 'The wind is the primary data product in this file. This variable contains the projection of the horizontal wind (at the tangent point) onto the line of sight direction. An entire altitude profile is observed simultaneously. An onion-peeling inversion is used on the raw observations to remove the effects of the integration along the line of sight. The line-of-sight wind is defined such that a positive value indicates motion towards the spacecraft. This direction is given by the Line_of_Sight_Azimuth variable. It is assumed that the vertical wind is zero, but even large vertical winds (~100 m/s) do not significantly affect this data product, since the line of sight is nearly horizontal everywhere. It should be noted that while this measurement is ascribed to a particular latitude, longitude and altitude, it is actually an average over many hundreds of kilometers horizontally, and 2.5-30 kilometers vertically (depending on the binning). See Harding et al. [2017, doi:10.1007/s11214-017-0359-3] for a more complete discussion of the inversion algorithm.  Knowledge of the 'zero wind phase' is needed for any instrument using Doppler shifts to determine winds. The zero wind phase is defined as the measured interference fringe phase that corresponds to the rest wavelength of the emission. For this initial data release, the zero wind phase has been determined by comparing a 60-day average of MIGHTI data to a 60-day average of the empirical Horizontal Wind Model 2014 (HWM14, Drob et al., 2015, doi:10.1002/2014EA000089), which is a fit to decades of previous wind measurements. At each time and location of a MIGHTI measurement, the MIGHTI measurement is simulated by integrating HWM14 along the line of sight, weighted by the observed volume emission rate as determined by the measured fringe amplitude profile. The 60-day-average difference between the measured and simulated phases is taken as the zero wind phase. This is done separately for each sensor (A and B), for each color (red and green), for each mode (day and night), and for each row (i.e., each altitude). This approach to determining the zero wind phase is analogous to the approach taken for the UARS/HRDI instrument (Hays et al., 1992, doi:10.1016/0032-0633(92)90119-9), which assumed that a long-term average of the meridional wind is zero. Although the long-term average altitude profile is constrained to match HWM14 in this initial MIGHTI data release, measured variations in time, latitude, longitude, and from day to day are retained using this approach. A future data release will leverage ICON's unique 'zero wind maneuver' to determine an independent zero wind phase.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "LOS Wind Precision (1 sample)",
          "ParameterKey": "ICON_L21_Line_of_Sight_Wind_Precision_1_Sample",
          "Description": "Master CDF CATDESC: 'Line-of-sight wind precision (1 sample)'. Master CDF VAR_NOTES: '['Various sources of error in MIGHTI winds are quantified with 1-sigma estimates and organized by their temporal persistence. These error sources are nearly uncorrelated with each other and can thus be added in quadrature. Users are encouraged to contact the MIGHTI team for assistance with error propagation.', 'The \"1 sample\" error variable quantifies errors that are uncorrelated from one exposure to the next, dominated by shot and dark noise in the detectors.  The correlation time of this error source is 30-60 seconds (i.e., the measurement cadence). The reported error is estimated from the fringe intensity and background. This is the recommended variable to use for analyses of wind fluctuations within a single day and a single altitude (e.g., gravity waves). Because the Level 2.2 data include interpolation of Level 2.1 data, some correlation remains between consecutive samples. Errors are slightly correlated across small altitude gaps as a result of the inversion.']'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "LOS Wind Precision (1 day)",
          "ParameterKey": "ICON_L21_Line_of_Sight_Wind_Precision_1_Day",
          "Description": "Master CDF CATDESC: 'Line-of-sight wind precision (1 day)'. Master CDF VAR_NOTES: '['Various sources of error in MIGHTI winds are quantified with 1-sigma estimates and organized by their temporal persistence. These error sources are nearly uncorrelated with each other and can thus be added in quadrature. Users are encouraged to contact the MIGHTI team for assistance with error propagation.', 'The \"1 Day\" error variable quantifies the error introduced by daily calibrations, which is correlated for an entire 24-hour period (00:00 - 23:59 UT). This is estimated from the magnitude of fluctuations in the daily-averaged phase, propagated through the inversion. Errors in day mode and night mode are nearly uncorrelated. For studies pertaining to atmospheric tidal modes that combine data from many days, this error can be treated as uncorrelated across time.']'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "LOS Wind Precision (Low Sig)",
          "ParameterKey": "ICON_L21_Line_of_Sight_Wind_Precision_Low_Signal_Effect",
          "Description": "Master CDF CATDESC: 'Line-of-sight wind precision (from low signal effect)'. Master CDF VAR_NOTES: '['Various sources of error in MIGHTI winds are quantified with 1-sigma estimates and organized by their temporal persistence. These error sources are nearly uncorrelated with each other and can thus be added in quadrature. Users are encouraged to contact the MIGHTI team for assistance with error propagation.', 'The \"Low Signal Effect\" error variable quantifies the error introduced by the imperfect correction for the signal-dependent phase shift, which is an effect seen in atmospheric and calibration-lamp fringes where the phase of the fringes is biased at very low signal levels. This is under investigation but could be caused by a charge trapping effect in the CCD. A correction has been implemented based upon the empirical relationship between measured phase and signal level of the calibration lamps for the first ~30 months of the mission. However, especially for cases with low signal levels, this correction is uncertain. The uncertainty in the resulting winds is estimated from the signal level and reported in this variable. It is likely to be correlated across samples nearby in time and space, but the correlation between different channels (red and green), sensors (MIGHTI-A and MIGHTI-B), and operating modes (Day and Night) is not known. Depending on the analysis being used, it could be treated as a systematic error or as a statistical error. Where this uncertainty is large, caution is recommended. For example, for winds in the core science region (90-105 km altitude), the magnitude of the correction is small or zero, but data in the red channel during the night and twilight are subject to a large correction (many tens of m/s) and the uncertainty is correspondingly large. A goal for future releases is to characterize and correct this effect more accurately.']'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "LOS Wind Precision (1 day)",
          "ParameterKey": "ICON_L21_Line_of_Sight_Wind_Accuracy",
          "Description": "Master CDF CATDESC: 'Line-of-sight wind accuracy'. Master CDF VAR_NOTES: '['Various sources of error in MIGHTI winds are quantified with 1-sigma estimates and organized by their temporal persistence. These error sources are nearly uncorrelated with each other and can thus be added in quadrature. Users are encouraged to contact the MIGHTI team for assistance with error propagation.', 'The \"Accuracy\" variable quantifies the error introduced by the zero-wind phase estimate. It is strongly correlated across time lags of days to weeks and becomes increasingly decorrelated for time lags longer than 2 precession cycles (96 days). This error is estimated from the discrepancy between various techniques of determining the zero-wind phase. This error source is irrelevant for most users studying perturbations from the mean (e.g., tides, waves), but may be important for studies of zonal mean winds, point comparisons with other data sets, and seasonal/long-term trends thereof. Errors are moderately correlated across small altitude gaps. Errors in day mode and night mode are nearly uncorrelated, implying there could be different offsets for day mode and night mode. This could be important for error propagation of odd-numbered migrating tides (e.g., DW1).']'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Line-of-sight Wind Error",
          "ParameterKey": "ICON_L21_Line_of_Sight_Wind_Error",
          "Description": "Master CDF CATDESC: 'Line-of-sight horizontal wind error profile'. Master CDF VAR_NOTES: 'The statistical (1-sigma) error in the line-of-sight wind. This is usually dominated by shot noise, but also includes the effects of dark and read noise, as well as calibrations errors (e.g., the zero wind calibration), and spacecraft pointing error (which affects the uncertainty in removing the spacecraft velocity from the observed velocity). Other systematic errors or biases may exist (e.g., the effect of gradients along the line of sight) which are not included in this variable. Errors in daily calibrations may create systematic patterns in winds that are constant for an entire 24 hour period (00:00 - 23:59 UT) but change from day to day.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "m/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "LST",
          "ParameterKey": "ICON_L21_Local_Solar_Time",
          "Description": "Master CDF CATDESC: 'Local solar time of each wind sample'. Master CDF VAR_NOTES: 'Local solar time at the location and time of each wind sample, calculated using the equation of time.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "hour",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Longitude",
          "ParameterKey": "ICON_L21_Longitude",
          "Description": "Master CDF CATDESC: 'WGS84 longitude of each wind sample'. Master CDF VAR_NOTES: 'The longitudes (0-360) of each point in the wind profile, evaluated using the WGS84 ellipsoid. The longitude only varies by several degrees from the bottom of the profile to the top. It should be noted that while a single longitude value (the tangent longitude) is given for each point, the observation is inherently a horizontal average over many hundreds of kilometers.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "deg",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Mag Lat",
          "ParameterKey": "ICON_L21_Magnetic_Latitude",
          "Description": "Master CDF CATDESC: 'Magnetic quasi-dipole latitude of each wind sample'. Master CDF VAR_NOTES: 'A two-dimensional array defining the magnetic quasi-dipole latitude of the two-dimensional data grid. The latitude varies only slightly (a few deg) with altitude, but this variation is included. It should be noted that while a single latitude value is given for each point, the observation is inherently a horizontal average over many hundreds of kilometers. Quasi-dipole latitude and longitude are calculated using the fast implementation developed by Emmert et al. (2010, doi:10.1029/2010JA015326) and the Python wrapper apexpy (doi.org/10.5281/zenodo.1214207). '. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "deg",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Mag Lon",
          "ParameterKey": "ICON_L21_Magnetic_Longitude",
          "Description": "Master CDF CATDESC: 'Magnetic quasi-dipole longitude of each wind sample'. Master CDF VAR_NOTES: 'A two-dimensional array defining the magnetic quasi-dipole longitude of the two-dimensional data grid. The longitude varies only slightly (a few deg) with altitude, but this variation is included. It should be noted that while a single longitude value is given for each point, the observation is inherently a horizontal average over many hundreds of kilometers. Quasi-dipole latitude and longitude are calculated using the fast implementation developed by Emmert et al. (2010, doi:10.1029/2010JA015326) and the Python wrapper apexpy (doi.org/10.5281/zenodo.1214207). Quasi-dipole longitude is defined such that zero occurs where the geodetic longitude is near 285 deg east (depending on latitude).'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "deg",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Relative VER",
          "ParameterKey": "ICON_L21_Relative_VER",
          "Description": "Master CDF CATDESC: 'Relative volume emission rate (VER) profile'. Master CDF VAR_NOTES: 'The volume emission rate (VER) obtained by scaling the fringe amplitude by a calibration factor. Pre-flight calibrations and on-orbit comparisons with ground-based instruments are used to determine the best possible calibration. The fringe amplitude has a dependence on temperature, which is corrected using the MSIS model. Because the on-orbit calibration is uncertain, and because the MSIS temperature correction is not perfect, caution should be exercised when absolute calibration is required, or when comparisons are being made between samples at different temperatures. Please contact the MIGHTI team before performing any studies that require absolute calibration. The statistical (1-sigma) error for this variable is provided in the variable ICON_..._Relative_VER_Error, though it is expected that systematic calibration errors dominate the total error. See the Fringe_Amplitude variable for a discussion of the inversion.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "ph/cm^3/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Relative VER",
          "ParameterKey": "ICON_L21_Relative_VER_Error",
          "Description": "Master CDF CATDESC: 'Relative volume emission rate (VER) error profile'. Master CDF VAR_NOTES: 'The statistical (1-sigma) error in the relative VER estimate. This error arises mostly from shot noise. Importantly, it is expected that systematic errors (e.g., calibration errors) dominate the total error, but they are not included in this variable.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "ph/cm^3/s",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "SZA",
          "ParameterKey": "ICON_L21_Solar_Zenith_Angle",
          "Description": "Master CDF CATDESC: 'Solar zenith angle of each wind sample'. Master CDF VAR_NOTES: 'Angle between the vectors towards the sun and towards zenith, at the location of each wind sample.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "deg",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Time",
          "ParameterKey": "ICON_L21_Time",
          "Description": "Master CDF CATDESC: 'Sample time at start, mid, stop of exposure. Number of msec since Jan 1, 1970.'. Master CDF VAR_NOTES: 'This variable is the same as Epoch, except it has another dimension which holds the start time, middle time, and stop time of each exposure.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "ms",
          "FillValue": -9223372036854775806,
          "Structure": {
            "Size": [
              3
            ]
          }
        },
        {
          "Name": "Time",
          "ParameterKey": "ICON_L21_UTC_Time",
          "Description": "Master CDF CATDESC: 'Sample time, midpoint of exposure.'. Master CDF VAR_NOTES: 'This variable is the same as Epoch but is formatted as a human-readable string.'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": " ",
          "FillValue": " "
        },
        {
          "Name": "VER Quality",
          "ParameterKey": "ICON_L21_VER_Quality",
          "Description": "Master CDF CATDESC: 'A quantification of the volume emission rate (VER) quality, from 0 (Bad) to 1 (Good)'. Master CDF VAR_NOTES: 'A quantification of the overall quality of the VER data. While the intent is that the variable VER_Error accurately characterizes the statistical error in the wind data, it is possible that systematic errors are present, or that the statistical error estimation is not accurate. If it is suspected that this is the case, the quality will be less than 1.0. If the data are definitely unusable, the the quality will be 0.0 and the sample will be masked. Users should exercise caution when the quality is less than 1.0.  This parameter can currently take 3 values: 0.0 (Bad), 0.5 (Caution), 1.0 (Good)'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "Good=1",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        },
        {
          "Name": "Wind Quality",
          "ParameterKey": "ICON_L21_Wind_Quality",
          "Description": "Master CDF CATDESC: 'A quantification of the wind quality, from 0 (Bad) to 1 (Good)'. Master CDF VAR_NOTES: 'A quantification of the overall quality of the wind data. While the intent is that the variable ICON_...Line_of_Sight_Wind_Error accurately characterizes the statistical error in the wind data, it is possible that systematic errors are present, or that the statistical error estimation is not accurate. If it is suspected that this is the case, the quality will be less than 1.0. If the data are definitely unusable, the quality will be 0.0 and the sample will be masked. Users should exercise caution when the quality is less than 1.0.  This parameter can currently take 3 values: 0.0 (Bad), 0.5 (Caution), 1.0 (Good)'. Notes not in Master CDF: 'The time index (the ISTP DEPEND_0 variable) for this parameter is Epoch_cdf.'",
          "Units": "Good=1",
          "FillValue": 9.96921e+36,
          "Structure": {
            "Size": [
              82
            ]
          }
        }
      ]
    }
  }
}