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CEDS v_2024_11_25 0.5 degree gridded data
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This Zenodo data entry is a documentation placeholder for the CEDS v_2024_11_25 0.5 degree gridded data released via ESGF.

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This release corrects files from CEDS v_2024_10_21 that have been redacted and replaced on ESGF.

Bulk emissions for all species except NMVOC's and supplementary solid biofuel emissions files from v_2024_11_25 are up to date and available on ESGF. 

Air emissions for all species, NMVOC bulk emissions, and supplementary speciated VOCs from v_2024_10_21 are up to date and available on ESGF.
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This gridded data is derived from CEDS v_2024_07_08 aggregate emissions release, which includes emissions data files by emission species (SO2, NOx, BC, OC, NH3, NMVOC,  CO, CO2, CH4, N2O), country, and sector produced by the July-08-2024 release of CEDS and released here:
https://zenodo.org/records/12803197

See the CEDS GitHub site for details including journal paper reference information and any known issues with this data:
https://github.com/JGCRI/CEDS

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Download Instructions
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This data set can be accessed via ESGF, for a list of ESGF nodes see:
https://www.earthsystemcog.org/projects/cog/ 

The input4MIPs project can be found by using “Search with options”. You can also go directly to: 
https://esgf-node.llnl.gov/search/input4mips.

The CEDS anthropogenic emissions data is published within the ESGF system under the following metadata:
:mip_era = 'CMIP6Plus'
:activity_id = “input4MIPs”;
:dataset_category = “emissions”;
:realm = “atmos”;
:institute = “PNNL-JGCRI”
:product = “primary-emissions-data”

This release has the file name:
input4MIPs.CMIP6Plus.CMIP.PNNL-JGCRI.CEDS-CMIP-2024-10-21.XXXXXXXXXXX

Please note that previous CEDS data is available for download through ESGF input4mips portal under mip_era = "CMIP6"

You can also search for a specific emission species under the “variable” category in your ESGF search. Note that to download ESGF data you will need to register for a free OpenID if you do not already have one.

Supplemental data with speciated VOC emissions and emissions from solid biofuel combustion are also provided through ESGF, see the README files linked below for further information. (metadata tagged as :product = “supplementary-emissions-data”).

Please note, the variables called xx-em-solid-biofuel are not open biomass emissions. These are a sub-set of anthropogenic emissions as described below.

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Data Notes
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CEDS emissions are provided at monthly resolution, on a 0.5 degree grid, with 50-years per data file as per ESGF formatting conventions (with 1850 CMIP6 pre-industrial emissions in their own file). (A 0.1° grid for recent decades is also available) Emissions are relatively smooth over the early portion of this time period, but annual data is supplied for consistency across the dataset. The files are in netcdf v4 (HDFv5) format with CF-compliant metadata.

Subsequent data releases since August 2016 are in a format with data in one variable, with sectors included as a dimension. 

The sectors in the netCDF files are:

sector	Description
0: AGR	Non-combustion agricultural sector
1: ENE	Energy transformation and extraction
2: IND	Industrial combustion and processes
3: TRA	Surface Transportation (Road, Rail, Other)
4: RCO	Residential, commercial, and other
5: SLV	Solvents
6: WST	Waste disposal and handling
7: SHP	International shipping (including VOCs from oil tanker loading/leakage)

Within the netCDF files the sector ids are:
sector:ids = "0: Agriculture; 1: Energy; 2: Industrial; 3: Transportation; 4: Residential, Commercial, Other; 5: Solvents production and application; 6: Waste; 7: International Shipping" ;

Gridded aircraft emissions are also supplied in a separate file with 25 vertical layers (using the CMIP5 historical emissions Lamarque et al. 2010, as drawn from Lee et al., as a template).
Note that aircraft emissions are zero in early years, but files are provided for all years consistency.

The gridded emissions incorporate a monthly seasonal cycle by sector drawing largely from the ECLIPSE project, Carbon Tracker, and EDGAR.

VOC speciation is provided at the 23 species resolution used in HTAP and RETRO. 

For use in setting aerosol size distribution and additional speciation (if desired), an auxiliary dataset emissions providing emissions from solid biomass combustion is also provided. Note that these are a subset of emissions in the main files. These data, therefore, should NOT be added to the emissions in the main files. (Note that no data files for CO2 emissions from solid biomass are released, as CO2 emissions from CEDS are from fossil fuels only.)

Supplementary "checksum" .csv text files that provide total global mass for each sector, month, and year are also available.

Filenames are in the following format:

EMISSION DATA FILE NAME FORMAT
Bulk Gridded emissions:
[em_species]-em-anthro_input4MIPs_emissions_CMIP_CEDS-2024-10-21_gn_YYYY01-ZZZZ12.nc
(where YYYY is the starting year contained in this file, and ZZZZ is the ending year)
netCDF variable name: [em_species]_em_anthro

Gridded aircraft emissions:
[em_species]-em-AIR-anthro_input4MIPs_emissions_CMIP_CEDS-2024-10-21_gn_YYYY01-ZZZZ12.nc
netCDF variable name: [em_species]_em_AIR_anthro

SUPPLEMENTAL EMISSION DATA FILE NAME FORMAT
Gridded biomass emissions:
[em_species]-em-SOLID-BIOFUEL-anthro_input4MIPs_emissions_CMIP_CEDS-2024-10-21-supplemental-data_gn_YYYY01-ZZZZ12.nc
netCDF variable name: [em_species]_em_SOLID_BIOFUEL_anthro

VOC speciation grids:
VOC01-alcohols-em-speciated-VOC-anthro_input4MIPs_emissions_CMIP_CEDS-2024-10-21-supplemental-data_gn_YYYY01-ZZZZ12.nc
netCDF variable name: VOC01_alcohols_em_speciated_VOC_anthro
(There is a separate README file with further information on VOC speciation -- see project web site. Note there is a variable naming inconsistency for these file - described in the VOC README)


Emissions are provided in units of mass flux, as a monthly average flux, as noted in the netCDF files. Units are total mass of the indicated species as follows:

SO2 : Mass flux of SOx, reported as SO2
NOx : Mass flux of NOx, reported as NO2
CO : Mass flux of CO
NMVOC : Mass flux of NMVOC (total mass emitted)
NH3 : Mass flux of NH3
BC : Mass flux of BC, reported as carbon mass (e.g., molecular weight 12)
OC : Mass flux of OC, reported as carbon mass (e.g., molecular weight 12)
CO2 : Mass flux of all oxidized carbon, reported as CO2
CH4 : Mass flux of CH4

For reference, the file: CEDS_gridcell_area_05.nc provides the grid cell areas used. (see project web site.)

Note that total monthly emissions were converted to fluxes using a 365 day calendar. If your model uses a different calendar, you should ideally adjust fluxes such that the integrated annual fluxes are maintained.

In addition to gridded data, aggregate data by country and sector is also available in units of kilo-tonne (kt) per year (see project github site for link: https://github.com/JGCRI/CEDS/). Note that country totals in these summary files do not include international shipping or aircraft emissions, which are reported under the "global" iso. 

GRIDDING METHODOLOGY

Emissions were first estimated at the level of country, sector, and fuel. Emissions by sector were then mapped to spatial grids by country and sector (several intermediate gridded sectors were combined to form the final release sectors for CMIP6Plus). Grid cells that contain more than one country have portions of emissions from each country. 

For recent decades, emissions were mapped to the grid level largely using the distribution of point sources and emissions from EDGAR (usually using year-specific EDGAR grids from 1970 through 2008). For some sectors, the emissions distribution varies over time, while for other sectors it was held constant. For most emission species, residential combustion is the dominant source by 1850, so emissions from the RCO sector were distributed using HYDE population distributions by 1900 (with blended spatial distributions between 1900 and 1970). For other sectors the emissions distribution within each country was held fixed before 1970. We aim to improve these distributions in the future, and would welcome contributions.

Because of the simplifying assumptions, emissions distributions, particularly in earlier years, should not be taken literally. Overall, however, anthropogenic emissions become small relative to either natural sources or mid-to-late 20th century emissions so we anticipate that these assumptions are not likely to have major impacts on global or regional modeling results.

For more details on the use of point sources in gridding methodology see:
https://zenodo.org/records/6949566/files/CEDS_Point_Source_Documentation.pdf

For more details on the gridding methodology see:
Feng, L., Smith, S. J., Braun, C., Crippa, M., Gidden, M. J., Hoesly, R., Klimont, Z., van Marle, M., van den Berg, M., and van der Werf, G. R.: The generation of gridded emissions data for CMIP6, Geosci. Model Dev., 13, 461–482, https://doi.org/10.5194/gmd-13-461-2020, 2020.

For more details on the underlying emissions data see:
Hoesly, R. M., Smith, S. J., Feng, L., Klimont, Z., Janssens-Maenhout, G., Pitkanen, T., Seibert, J. J., Vu, L., Andres, R. J., Bolt, R. M., Bond, T. C., Dawidowski, L., Kholod, N., Kurokawa, J.-I., Li, M., Liu, L., Lu, Z., Moura, M. C. P., O'Rourke, P. R., and Zhang, Q. (2018) Historical (1750–2014) anthropogenic emissions of reactive gases and aerosols from the Community Emissions Data System (CEDS), Geosci. Model Dev., 11, 369-408. doi: 10.5194/gmd-11-369-2018. 

and for the latest updates see:
https://github.com/JGCRI/CEDS/

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Contact Info:
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ssmith@pnnl.gov
rachel.hoesly@pnnl.gov