Emissions Data Projects
September 2016 – see the main CEDS project page for a link to the CEDS gitHub repository. Issues with the released data will be documented there on the issues tab (search for the CMIP6 tag and make sure to include closed issues).. Data users can also submit issues. Information on data updates subsequent to the CMIP6 data release can also be found there.
Gridded Emissions Data Update (May 2017)
Users of previously released gridded data (versions v2016-06-18 and v2016-07-26) should update to the May 2017 versions of the CMIP6 historical data to avoid the following issues.
Data users have reported two issues with the older CMIP6 gridded emissions data releases. These are: 1) year-to-year inconsistencies in the country/sector level gridded data and 2) a small error in the intended seasonal distribution of emissions. Neither of these issues change total emissions by country and sector.
Issue 1) above regarding gridded emissions distributions causes non-trivial, and sometimes sudden shifts, in the emission distribution within countries. These shifts are most noticeable for large countries such as the USA and China. Users have reports that these can have significant impacts on results in some models (such as the magnitude of aerosol indirect effects).
The May 2017 and later gridded data releases on ESGF corrects both of these issues.
Documentation of these issues, including time series and spatial graphs are available at https://goo.gl/tGrc27.
Gridded Emissions Data
Emissions data from the CEDS Project for use in CMIP6 historical and preindustrial control runs is being distributed through the Earth System Grid Federation (ESGF). Please see the README file available below before using this data. Note that revisions to gridded data listed below changed only spatial allocation within countries – CEDS emissions by country and sector remained at the values originally released in v2016-07-26 (v2017-05-18 for CO2 and CH4).
CMIP6 Gridded Data Release History
- September 2017: New versions of aircraft gridded emissions (ver. 2017-08-30 and 2017-10-05 for SO2) were published on ESGF. This is basically a cosmetic change, whereby aircraft emissions were set to zero before 1920. NOTE: You may have to check the “Show All Versions“ box on ESGF to see CEDS supplemental emissions files (which did not change from the previous release.)
- August 2017: We have released a “rough cut” extension of CH4 emissions between1850 and 1970 (in decadal increments) for experiments that require CH4 emissions over all years. This data is on ESGF and is labeled as supplemental-data (ver. 2017-05-18).
- May 2017: *** IMPORTANT *** revised gridded data (ver. 2017-05-18) were published that corrected some errors in the previous gridded data (ver. 2016-06-18, and 2016-07-26, see README and analysis of difference between the new and old data sets at: https://goo.gl/tGrc27). The new release also included CO2 emissions (all years) and CH4 emissions (from 1970 forward).
- September 2016: files were re-published in a new format (with sectors contained within a dimension) due to a limitation in ESGF software on some nodes. (version numbers were amended with -sectordim)
- June and July 2016: preindustrial (1750-1850) data (ver. 2016-06-18) and historical 1851-2014 (ver. v2016-07-26) for aerosol and reactive gas species were published on ESGF.
The CEDS anthropogenic emissions data is published within the ESGF system under the following metadata:
:activity_id = “input4MIPs”;
:dataset_category = “emissions”;
:realm = “atmos”;
:institute = “PNNL-JGCRI”
:product = “primary-emissions-data”
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 in the README.
See: https://www.earthsystemcog.org/projects/cog/ for a list of ESGF nodes. The input4MIPs project can be found by using “Search with options”. You can also go directly to: https://esgf-node.llnl.gov/search/input4mips.
Auxiliary Gridded Emissions Information
Only the gridded netCDF emission data files have been provided through ESGF. Several auxiliary files are provided here including:
- A README (September 2017) text file with data description and other details
- A single Checksum file that provides machine readable totals by species, sector, month, and year for 1750-through-2014
- netCDF file with assumed grid cell areas
- Comparison graphs show the new time series as compared to the RCP historical data used in CMIP5 (see README file for a discussion) for Pre-industrial (1750-1850) and for 1850-2014
- VOC README file for the speciated VOC emissions (released as supplementary gridded data on ESGF)
Future emission scenario data have been produced consistent with the CEDS historical emissions and are also available via ESGF by the IAMC. For details see the CMIP6 Forcing Datasets Summary google doc . As a service to assist modelers, checksum information for those future scenarios are provided at the link below.
- Checksum files that provides machine readable totals by species, sector, month, and year for 2015 – 2100 for each IAMC scenario.
The CMIP6 data release has been documented in the following papers:
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.: Historical (1750–2014) anthropogenic emissions of reactive gases and aerosols from the Community Emissions Data System (CEDS), Geosci. Model Dev., 11, 369-408, https://doi.org/10.5194/gmd-11-369-2018, 2018.
Supplementary files are available for download with the article including:
- Zip file supplement
- Emissions by country
- Emissions by sector and country
- Emissions by fuel
- mapping file with country definitions
- Supplemental Figure and Tables
- Supplemental Data and Assumptions
Updated Supplemental files which now include CO2, CH4 (from 1960), supplemental CH4 (extension to 1850), as well as data for all small countries/regions/islands (rather than aggregate regions, i.e. Other Asia or Other Africa, as in the original supplement) are available HERE.
CMIP6 gridded emissions data generation, focusing on historical anthropogenic and future scenarios, is discussed here:
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 (2020), Geosci. Model Dev., 13, 461-482, https://doi.org/10.5194/gmd-13-461-2020 .
(Back to the CEDS Project)
Emissions of anthropogenic aerosol and precursor compounds substantially alter the Earth’s radiative balance, change the oxidation capacity of the atmosphere, alter cloud processes and precipitation amounts, and result in significant impacts on human health and ecosystems. One of the primary tools used to examine these effects are global models. There are a number of characteristics of emissions that can influence model results, such as seasonality and assumed injection height, that are not either uncertain or not specified in current global datasets.
The aim of Emissions-MIP is to quantify the influence of these characteristics on model results. The project has two phases. In Phase 1, atmosphere-only simulations will be used to examine a impact of a suite of emission perturbations. The results from Phase I will be evaluated to select a small set of perturbations to examine using ensembles of coupled model simulations in Phase 2.
Currently participating models/modeling groups include: PNNL (E3SM), PNNL (CESM1), GSFC (GEOS), GISS, GFDL, NCAR, HadGEM-UKCA, OsloCTM3, MIROC-SPRINTARS, NorESM.
Current Status (June 2021)
The Phase 1 experiments use atmosphere-only model runs with specified ocean temperatures and nudged winds run for six year period, reporting concentration, deposition, and forcing variables. While these runs do not include fully coupled dynamics, these are computationally less expensive and we can, therefore, quantify the magnitude of any effects for a larger number of perturbations. We can also more directly compare results from both ESMs and CTMs in the Phase 1 experiments.
The experimental protocol for Phase 1a was developed fall 2020. The reference case uses CMIP6 historical emissions. The current experimental protocol is available here.
The following five perturbation cases were identified for Phase 1a:
As of June 2021, eight models have completed these simulations and two are partially completed. A version of the CMIP6 emissions data with no seasonality for use in these experiments are available at the Emissions-MIP data repository.
Phase 1b simulations will focus on uncertainties in the spatial distribution of ocean shipping emissions. The experimental protocol is now being tested and will be released once it is finalized.
This project is using the ESMVal tool for analyzing model results. We would like to thank the ESMValtool team for technical assistance.
More modeling groups are invited to join the project. Please contact firstname.lastname@example.org for further information.