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ESA Greenhouse Gases Climate Change Initiative (GHG CCI): SCIAMACHY CH4 Level 2 Data Product (CH4_SCI_IMAP), version 7.1, generated with the IMAP-DOAS algorithm

Latest Data Update: 2016-04-05
Status: Superseded
Online Status: ONLINE
Publication State: Published
Publication Date: 2016-04-11
Download Stats: last 12 months
Dataset Size: 3.25K Files | 2GB

This dataset has been superseded. See Latest Version here

Part of the European Space Agency's (ESA) Greenhouse Gases (GHG) Climate Change Initiative (CCI) project and the Climate Research Data Package Number 3 (CRDP#3), the XCH4 SCI product comprises a level 2, column-averaged dry-air mole fraction (mixing ratio) for methane (CH4). The product has been produced using data acquired from the SWIR spectra (channel 6) of the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) on board the European Space Agency's environmental research satellite ENVISAT.

This product has been derived by applying the IMAP-DOAS algorithm developed at the University of Heidelberg and SRON to the SCIAMACHY data. This procedure and the algorithms validity are thoroughly described in Frankenberg et al (2011). A second product is also available which has been generated using the Weighting Function Modified DOAS (WFM-DOAS) algorithm.

The data product is stored per orbit in a single NetCDF4 file. Retrieval results are provided for the individual SCIAMACHY spatial footprints, no averaging having been applied. The product file contains the key products and information relevant to using the data, such as the vertical layering and averaging kernels. For further details on the product, including the IMAP algorithm and the SCIAMACHY instrument, please see the associated product user guide (PUG) or the Algorithm Theoretical Basis Document in the documentation section.

The GHG-CCI team encourage all users of their products to register with them to receive information on any updates or issues regarding the data products and to receive notification of new product releases. To register, please use the following link:

Citable as:  ESA CCI GHG project team (2016): ESA Greenhouse Gases Climate Change Initiative (GHG CCI): SCIAMACHY CH4 Level 2 Data Product (CH4_SCI_IMAP), version 7.1, generated with the IMAP-DOAS algorithm. Centre for Environmental Data Analysis, date of citation.
Abbreviation: Not defined
Keywords: ESA, GHG, CCI, CH4, IMAP, Greenhouse Gas


Previous Info:
No news update for this record
Previously used record identifiers:
No related previous identifiers.
Access rules:
Public data: access to these data is available to both registered and non-registered users.
Use of these data is covered by the following licence: When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record.
Data lineage:

Data were processed by the ESA CCI GHG project team and supplied to CEDA as part of the ESA CCI Open Data Portal Project

File Format:
Data are in NetCDF format

Process overview

This dataset was generated by instruments deployed on platforms as listed below.

Instrument/Platform pairings

Envisat - SCIAMACHY Deployed on: Envisat

Mobile platform operations

Mobile Platform Operation 1 Mobile Platform Operation for: Envisat
Output Description


  • units: 1
  • long_name: Chi-squared
  • var_id: chi2_co2
  • units: m-2
  • long_name: Dry airmass per layer
  • var_id: dry_airmass_layer
  • units: cm-2
  • long_name: ECMWF H2O vertical column density
  • var_id: h2o_ecmwf
  • units: m
  • standard_name: height
  • long_name: Height
  • var_id: surface_elevation
  • units: 1
  • var_id: xch4_quality_flag
  • long_name: Retrieval quality flag
  • units: degrees
  • long_name: Sensor zenith angle
  • standard_name: sensor_zenith_angle
  • var_id: sensor_zenith_angle
  • units: degrees
  • long_name: Solar zenith angle
  • var_id: solar_zenith_angle
  • standard_name: solar_zenith_angle
  • units: Kelvin
  • var_id: surface_temperature
  • long_name: Surface temperature
  • units: 1e-9
  • var_id: ch4_profile_apriori
  • long_name: a priori profile of dry-air mole fraction of atmospheric methane (ppb)
  • units: 1e-6
  • long_name: column-average dry-air mole fraction of atmospheric carbon dioxide (ppm) as used in XCH4 proxy
  • var_id: xco2_retrieved
  • units: 1e-9
  • var_id: xch4
  • long_name: column-average dry-air mole fraction of atmospheric methane (ppb)
  • units: 1
  • long_name: normalized column averaging kernel
  • var_id: xch4_averaging_kernel
  • units: hPa
  • long_name: pressure levels
  • var_id: pressure_levels
  • units: 1
  • long_name: pressure weights
  • var_id: pressure_weight
  • units: 1e-9
  • long_name: prior column-average dry-air mole fraction of atmospheric methane (ppb)
  • var_id: xch4_prior

Co-ordinate Variables

  • units: degrees_north
  • standard_name: latitude
  • var_id: latitude
  • long_name: latitude
  • units: degrees_east
  • standard_name: longitude
  • var_id: longitude
  • long_name: longitude
  • long_name: time
  • standard_name: time
  • var_id: time
Temporal Range
Start time:
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Geographic Extent