Dataset
ESA Precursors for Aerosols and Ozone Climate Change Initiative (Precursors_cci): daily L3 HCHO from OMI, version 2.0
Latest Data Update: 2026-10-05
Status: Completed
Online Status: ONLINE
Publication State: Published
Publication Date: 2026-10-21
Download Stats: last 12 months
Dataset Size: 6.31K Files | 1TB
Abstract
The Formaldehyde (HCHO) Climate Data Record (CDR) product is a Level 3 HCHO product developed by using satellite data from the OMI instrument (on AURA) as part of the ESA Climate Change Initiative (CCI) Precursors for Aerosols and Ozone project.
This dataset provides gridded HCHO tropospherical column densities of daily 0.25°x0.25° resolution grids from October 2004 to December 2024.
The L3 product is based on the Level 2 HCHO product created for the Precursors_cci project.
Compared to the operational TROPOMI product, the air mass factors have been reprocessed using an update albedo climatology, and the CAMS Reanalysis Model for the a priori vertical profiles. The background correction and the quality values have also been updated.
In addition to the main product results, such as HCHO slant column, vertical column and air mass factor, the Level 3 data files contain several additional parameters and diagnostic information such as uncertainties, a priori profiles and averaging kernels.
The version number is 2.0. Data are available in NetCDF format. https://doi.org/10.18758/bf145884
The European Space Agency (ESA) Precursors for Aerosol and Ozone Climate Change Initiative (Precursors CCI) project is part of ESA's Climate Change Initiative (CCI) to produce long term datasets of Essential Climate Variables derived from global satellite data (https://climate.esa.int/en/projects/precursors-for-aerosols-and-ozone/).
Citable as: De Smedt, I.; Vlietinck, J.; Yu, H.; Theys, N.; Danckaert, T.; Van Roozendael, M. (2026): ESA Precursors for Aerosols and Ozone Climate Change Initiative (Precursors_cci): daily L3 HCHO from OMI, version 2.0. NERC EDS Centre for Environmental Data Analysis, date of citation. https://catalogue.ceda.ac.uk/uuid/2856b5dd4b7d4c528d36e3679d2d706e
Abbreviation: Not defined
Keywords: Not defined
Details
| Previous Info: |
No news update for this record
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|---|---|
| Previously used record identifiers: |
No related previous identifiers.
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| 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(s): https://artefacts.ceda.ac.uk/licences/specific_licences/esacci_precursors_for_aerosols_and_ozone_terms_and_conditions.pdf When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record. |
| Data lineage: |
Data were produced by the project team and supplied for archiving at the Centre for Environmental Data Analysis (CEDA). |
| File Format: |
netcdf
|
Process overview
This dataset was generated by a combination of instruments deployed on platforms
and computations as detailed below.
Instrument/Platform pairings
| OMI (Ozone Measuring Instrument) | Deployed on: EOS-AURA |
Computation Element: 1
| Title | Computation for ESA Precursors for Aerosols and Ozone Climate Change Initiative (Precursors_cci): daily L3 HCHO from OMI, version 2.0 |
| Abstract | This dataset provides gridded HCHO tropospherical column densities of daily 0.25°x0.25° resolution grids from October 2004 to December 2024. The L3 product is based on the Level 2 HCHO product created for the Precursors_cci project. Compared to the operational TROPOMI product, the air mass factors have been reprocessed using an update albedo climatology, and the CAMS Reanalysis Model for the a priori vertical profiles. The background correction and the quality values have also been updated. |
| Input Description | None |
| Output Description | None |
| Software Reference | None |
| Output Description | None |
- units: 1
- var_id: qa_L3
- long_name: HCHO QA L3
- units: molec/cm^2
- var_id: HCHO_slant_column_number_density
- long_name: HCHO SCD
- units: molec/cm^2
- var_id: HCHO_slant_column_number_density_uncertainty
- long_name: HCHO SCDE
- standard_name: troposphere_mole_content_of_formaldehyde
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density
- long_name: HCHO VCD
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_apriori
- long_name: HCHO VCD CTM
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_std
- long_name: HCHO VCD STD
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_tr
- long_name: HCHO VCD TR
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_clear
- long_name: HCHO VCD clear
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_clear_OS
- long_name: HCHO VCD clear OS
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_clear_std
- long_name: HCHO VCD clear STD
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_clear_tr
- long_name: HCHO VCD clear TR
- units: 1
- var_id: tropospheric_HCHO_column_number_density_count
- long_name: HCHO VCD count
- units: 1
- var_id: tropospheric_HCHO_column_number_density_weight
- long_name: HCHO VCD weight
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_background_correction
- long_name: HCHO VCD0
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_uncertainty_random
- long_name: HCHO VCDER
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_uncertainty_systematic
- long_name: HCHO VCDES
- units: molec/cm^2
- var_id: tropospheric_HCHO_column_number_density_uncertainty_systematic_kernel
- long_name: HCHO VCDESK
- units: ppv
- var_id: HCHO_volume_mixing_ratio_dry_air_apriori
- long_name: HCHO a priori profile
- units: molec/cm^2
- var_id: HCHO_slant_column_number_density_corrected
- long_name: HCHO bc-corrected SCD
- units: 1
- var_id: HCHO_averaging_kernel
- long_name: HCHO column averaging kernel
- units: 1
- var_id: HCHO_averaging_kernel_clear
- long_name: HCHO column averaging kernel, no cloud correction
- units: 1
- var_id: tropospheric_HCHO_column_number_density_amf
- long_name: HCHO tropospheric AMF (340 nm)
- units: 1
- var_id: tropospheric_HCHO_column_number_density_amf_clear
- long_name: HCHO tropospheric clear AMF (340 nm)
- units: 1
- var_id: count
- long_name: Harp count
- units: 1
- var_id: weight
- long_name: Harp weight
- units: 1
- var_id: HCHO_slant_column_number_density_rms
- long_name: RMS of the DOAS fits
- units: degree
- var_id: solar_zenith_angle
- standard_name: solar_zenith_angle
- long_name: SZA
- units: degree
- standard_name: sensor_zenith_angle
- var_id: sensor_zenith_angle
- long_name: VZA
- units: 1
- var_id: cloud_fraction
- long_name: cloud fraction
- units: hPa
- var_id: cloud_pressure
- long_name: cloud pressure
- units: hPa
- var_id: ctm_sigma_a
- long_name: ctm sigma-values a
- units: 1
- var_id: ctm_sigma_b
- long_name: ctm sigma-values b
- units: days
- var_id: eff_date
- long_name: effective date
- units: 1
- var_id: eff_fract_day
- long_name: effective fractional day in local solar time
- var_id: latitude_bounds
- long_name: grid latitude bounds
- var_id: longitude_bounds
- long_name: grid longitude bounds
- units: 1
- var_id: intensity_weighted_cloud_fraction
- long_name: intensity-weighted cloud radiance fraction (340 nm)
- units: 1
- long_name: land sea mask
- var_id: land_water_mask
- units: 1
- standard_name: atmosphere_hybrid_sigma_pressure_coordinate
- var_id: layer
- long_name: layer dimension index
- units: 1
- var_id: surface_albedo
- long_name: surface LER (340 nm)
- units: hPa
- long_name: surface pressure
- var_id: surface_pressure
Co-ordinate Variables
- units: degree_north
- standard_name: latitude
- var_id: latitude
- units: degree_east
- standard_name: longitude
- var_id: longitude
- standard_name: time
- var_id: time
- units: days
- long_name: number of days since 1995-01-01
Coverage
Temporal Range
Start time:
2004-10-01T00:00:00
End time:
2024-12-30T23:59:59
Geographic Extent
90.0000° |
||
-180.0000° |
180.0000° |
|
-90.0000° |
Related parties