# \#egg4 **URL:** https://forum.ecmwf.int/tag/egg4/4.md [Latest](https://forum.ecmwf.int/latest.md) · [Categories](https://forum.ecmwf.int/categories.md) · [Tags](https://forum.ecmwf.int/tags.md) --- ## [Question about availability of CAMS EGG4 Version 2 (2003–2023)](https://forum.ecmwf.int/t/question-about-availability-of-cams-egg4-version-2-2003-2023/15140)
**Author:** [@Mitch\_John](https://forum.ecmwf.int/u/Mitch_John)\ **Replies:** 0\ **Last updated:** [8 July 2026 08:19 UTC](https://forum.ecmwf.int/t/question-about-availability-of-cams-egg4-version-2-2003-2023/15140 "2026-07-08T08:19:10Z")
Dear CAMS EGG4 Support Team, I am currently using the CAMS Global Greenhouse Gas Reanalysis (EGG4) dataset for scientific research. According to the CAMS Validation Report (2024, D82.4.2.2) (https://atmosphere.copernic… --- ## [Can i Use EGG4 Dataset in wrfchem](https://forum.ecmwf.int/t/can-i-use-egg4-dataset-in-wrfchem/11257)
**Author:** [@Muhamamd\_Burhan\_Khalid](https://forum.ecmwf.int/u/Muhamamd_Burhan_Khalid)\ **Replies:** 0\ **Last updated:** [10 February 2025 10:45 UTC](https://forum.ecmwf.int/t/can-i-use-egg4-dataset-in-wrfchem/11257 "2025-02-10T10:45:03Z")
Hi i am working with wrfchem and want to use greenhouse gases parameters can i use data form this source (CAMS global greenhouse gas reanalysis (EGG4)) for simulation if yes then how i can change units of chemical param… --- ## [CAMS global greenhouse gas reanalasys (EGG4) (3-hourly) avaibility after 2020](https://forum.ecmwf.int/t/cams-global-greenhouse-gas-reanalasys-egg4-3-hourly-avaibility-after-2020/1292)
**Author:** [@Marine\_Claeys](https://forum.ecmwf.int/u/Marine_Claeys)\ **Replies:** 0\ **Last updated:** [15 September 2023 08:44 UTC](https://forum.ecmwf.int/t/cams-global-greenhouse-gas-reanalasys-egg4-3-hourly-avaibility-after-2020/1292 "2023-09-15T08:44:40Z")
Will EGG4 data be available for the year 2021 ? --- ## [Exception: Resource cams-global-ghg-reanalysis-egg4 not found. Please help with this error. I am not able to download the data for CAMS GHG emissions](https://forum.ecmwf.int/t/exception-resource-cams-global-ghg-reanalysis-egg4-not-found-please-help-with-this-error-i-am-not-able-to-download-the-data-for-cams-ghg-emissions/1429)
**Author:** [@Vinayak\_Huggannavar](https://forum.ecmwf.int/u/Vinayak_Huggannavar)\ **Replies:** 1\ **Last updated:** [2 January 2022 13:19 UTC](https://forum.ecmwf.int/t/exception-resource-cams-global-ghg-reanalysis-egg4-not-found-please-help-with-this-error-i-am-not-able-to-download-the-data-for-cams-ghg-emissions/1429 "2022-01-02T13:19:00Z")
Exception: Resource cams-global-ghg-reanalysis-egg4 not found. Please help with this error. I am not able to download the data for CAMS GHG emissions --- ## [Why do we get different values for variables for the same CAMS product depending on the request (one or several dates)?](https://forum.ecmwf.int/t/why-do-we-get-different-values-for-variables-for-the-same-cams-product-depending-on-the-request-one-or-several-dates/1566)
**Author:** [@Marie-France\_LARIF](https://forum.ecmwf.int/u/Marie-France_LARIF)\ **Replies:** 5\ **Last updated:** [19 October 2021 11:37 UTC](https://forum.ecmwf.int/t/why-do-we-get-different-values-for-variables-for-the-same-cams-product-depending-on-the-request-one-or-several-dates/1566 "2021-10-19T11:37:59Z")
We are currently trying to retrieve all available CAMS from the cams-global-atmospheric-composition-forecasts dataset which match our needs (twice a day with specific variables, from 2017 to now). To do so, we've been s… --- ## [Why the dataset 'CAMS global greenhouse gas reanalysis (EGG4) monthly averaged fields" don't caculate the Carbon dioxide total column dry mole fraction?](https://forum.ecmwf.int/t/why-the-dataset-cams-global-greenhouse-gas-reanalysis-egg4-monthly-averaged-fields-dont-caculate-the-carbon-dioxide-total-column-dry-mole-fraction/1058)
**Author:** [@Mitch\_John](https://forum.ecmwf.int/u/Mitch_John)\ **Replies:** 0\ **Last updated:** [15 September 2021 03:02 UTC](https://forum.ecmwf.int/t/why-the-dataset-cams-global-greenhouse-gas-reanalysis-egg4-monthly-averaged-fields-dont-caculate-the-carbon-dioxide-total-column-dry-mole-fraction/1058 "2021-09-15T03:02:28Z")
Hi everyone, The CAMS dataset in the website https://ads.atmosphere.copernicus.eu/cdsapp#!/search?type=dataset provide some gresshouse dataset,which is very useful for global climate research. However,in this websi… --- ## [Why the dataset "CAMS global greenhouse gas reanalysis (EGG4) monthly averaged fields" don't caculate the Carbon dioxide total column dry mole fraction?](https://forum.ecmwf.int/t/why-the-dataset-cams-global-greenhouse-gas-reanalysis-egg4-monthly-averaged-fields-dont-caculate-the-carbon-dioxide-total-column-dry-mole-fraction/1356)
**Author:** [@Mitch\_John](https://forum.ecmwf.int/u/Mitch_John)\ **Replies:** 0\ **Last updated:** [14 September 2021 02:44 UTC](https://forum.ecmwf.int/t/why-the-dataset-cams-global-greenhouse-gas-reanalysis-egg4-monthly-averaged-fields-dont-caculate-the-carbon-dioxide-total-column-dry-mole-fraction/1356 "2021-09-14T02:44:00Z")
Hi everyone, The CAMS dataset in the website https://ads.atmosphere.copernicus.eu/cdsapp#!/search?type=dataset provide some gresshouse dataset,which is very useful for global climate research. However,in this websi… --- ## [CAMS Multi-Level CO2 Mole Fraction Product](https://forum.ecmwf.int/t/cams-multi-level-co2-mole-fraction-product/1053)
**Author:** [@Farhan\_Mustafa](https://forum.ecmwf.int/u/Farhan_Mustafa)\ **Replies:** 1\ **Last updated:** [14 September 2021 02:43 UTC](https://forum.ecmwf.int/t/cams-multi-level-co2-mole-fraction-product/1053 "2021-09-14T02:43:00Z")
Hi everyone, I am working on regional uncertainties in the satellite XCO2 products retrieved using various algorithms. I need to know that is there any CAMS product that provides CO2 molar fraction at different pressure…