# CAMS - Datasets and Usage **URL:** https://forum.ecmwf.int/c/datasets-and-usage/cams-datasets-and-usage/14.md?page=3 [Latest](https://forum.ecmwf.int/latest.md) · [Categories](https://forum.ecmwf.int/categories.md) · [Tags](https://forum.ecmwf.int/tags.md) **Page:** 4 --- ## [Which Digital Elevation Model (DEM) for single-level parameters in the "CAMS global atmospheric composition forecasts" database?](https://forum.ecmwf.int/t/which-digital-elevation-model-dem-for-single-level-parameters-in-the-cams-global-atmospheric-composition-forecasts-database/1551)
**Author:** [@Jason\_Champion-Legen](https://forum.ecmwf.int/u/Jason_Champion-Legen)\ **Replies:** 0\ **Last updated:** [14 January 2022 14:37 UTC](https://forum.ecmwf.int/t/which-digital-elevation-model-dem-for-single-level-parameters-in-the-cams-global-atmospheric-composition-forecasts-database/1551 "2022-01-14T14:37:27Z")
Hello everyone, I am interested in using several single-level parameters from the CAMS global atmospheric composition forecasts database, e.g., aerosol optical depth and typology, water vapor and ozone content. These da… --- ## [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… --- ## [AOD and PM2.5 at night](https://forum.ecmwf.int/t/aod-and-pm2-5-at-night/1531)
**Author:** [@zh\_tu](https://forum.ecmwf.int/u/zh_tu)\ **Replies:** 0\ **Last updated:** [16 July 2021 03:34 UTC](https://forum.ecmwf.int/t/aod-and-pm2-5-at-night/1531 "2021-07-16T03:34:32Z")
How do reanalysis data get a precise AOD at night? There's no light at night, maybe aerosol optical depth cannot be well measured? Besides, what's the process of computing night PM2.5? --- ## [GFAS daily total mass of CO2 emitted and CO2 concentration](https://forum.ecmwf.int/t/gfas-daily-total-mass-of-co2-emitted-and-co2-concentration/1613)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [1 April 2021 10:27 UTC](https://forum.ecmwf.int/t/gfas-daily-total-mass-of-co2-emitted-and-co2-concentration/1613 "2021-04-01T10:27:23Z")
User can estimate the daily total mass of CO2 emitted with GFAS data by multiplying the flux with the area of each grid cell and number of seconds in the day. However, if users want to get to the CO2 concentration, then … --- ## [Time issue when using CAMS European Air Quality forecast netCDF data in ArcGIS](https://forum.ecmwf.int/t/time-issue-when-using-cams-european-air-quality-forecast-netcdf-data-in-arcgis/1564)
**Author:** [@Kevin\_Marsh](https://forum.ecmwf.int/u/Kevin_Marsh)\ **Replies:** 0\ **Last updated:** [19 March 2021 17:58 UTC](https://forum.ecmwf.int/t/time-issue-when-using-cams-european-air-quality-forecast-netcdf-data-in-arcgis/1564 "2021-03-19T17:58:34Z")
When using netCDF files from CAMS European Air Quality forecasts from the ADS in ArcGIS, the 'time' values may not be displayed correctly. In netCDF files which follow the CF conventions the 'time' variable is normall… --- ## [CHIMERE model has days when PM2.5 is bigger then PM10](https://forum.ecmwf.int/t/chimere-model-has-days-when-pm2-5-is-bigger-then-pm10/1049)
**Author:** [@Neda\_Aleksandrov](https://forum.ecmwf.int/u/Neda_Aleksandrov)\ **Replies:** 0\ **Last updated:** [26 February 2021 10:39 UTC](https://forum.ecmwf.int/t/chimere-model-has-days-when-pm2-5-is-bigger-then-pm10/1049 "2021-02-26T10:39:06Z")
Hello, I am using regional reanalysis data from CAMS European air quality forecasts. To be precise, I am using data from CHIMERE model. During my research , I found out that in some area (e.g. the point whose coordinate… --- ## [Differences between CH4 and CH4\_C](https://forum.ecmwf.int/t/differences-between-ch4-and-ch4-c/1036)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 2\ **Last updated:** [11 January 2021 10:34 UTC](https://forum.ecmwf.int/t/differences-between-ch4-and-ch4-c/1036 "2021-01-11T10:34:24Z")
What's the difference between CH4 data accessible on request only (or through MARS) and the CH4\_C forecast data (latest three days) available on the ECMWF FTP server? --- ## [About CAMS forecast system upgrades](https://forum.ecmwf.int/t/about-cams-forecast-system-upgrades/1096)
**Author:** [@Anabelle](https://forum.ecmwf.int/u/Anabelle)\ **Replies:** 0\ **Last updated:** [29 December 2020 14:34 UTC](https://forum.ecmwf.int/t/about-cams-forecast-system-upgrades/1096 "2020-12-29T14:34:30Z")
Both the CAMS and ECMWF’s NWP forecasting systems are based on the IFS (Integrated Forecasting System); CAMS runs the IFS in a slightly different configuration. The CAMS configuration makes use of additional detailed che… --- ## [What more processing is needed to use the data of GFAS analysis surface parameters？](https://forum.ecmwf.int/t/what-more-processing-is-needed-to-use-the-data-of-gfas-analysis-surface-parameters/1030)
**Author:** [@Ming\_Zheng](https://forum.ecmwf.int/u/Ming_Zheng)\ **Replies:** 0\ **Last updated:** [25 December 2020 00:52 UTC](https://forum.ecmwf.int/t/what-more-processing-is-needed-to-use-the-data-of-gfas-analysis-surface-parameters/1030 "2020-12-25T00:52:31Z")
Hello everyone,I downloaded the Wildfire flux of Carbon Dioxide data，I've converted NetCDF to TIFF，but I found that the value of this data is almost zero，A small number of non-zero values are also very small，As shown in … --- ## [About the data of GFAS analysis surface parameters](https://forum.ecmwf.int/t/about-the-data-of-gfas-analysis-surface-parameters/1555)
**Author:** [@Ming\_Zheng](https://forum.ecmwf.int/u/Ming_Zheng)\ **Replies:** 0\ **Last updated:** [24 December 2020 13:14 UTC](https://forum.ecmwf.int/t/about-the-data-of-gfas-analysis-surface-parameters/1555 "2020-12-24T13:14:18Z")
Hello everyone！ As the title shows，I downloaded the Wildfire flux of Carbon Dioxide data，but I found that the value of this data is almost zero，A small number of non-zero values are also very small，As shown in the figur… --- ## [CAMS European reanalysis data : PM10 Composite](https://forum.ecmwf.int/t/cams-european-reanalysis-data-pm10-composite/1081)
**Author:** [@IMANE\_SEKMOUDI](https://forum.ecmwf.int/u/IMANE_SEKMOUDI)\ **Replies:** 0\ **Last updated:** [20 December 2020 16:52 UTC](https://forum.ecmwf.int/t/cams-european-reanalysis-data-pm10-composite/1081 "2020-12-20T16:52:44Z")
Dear committee, As part of my scientific research, i use CAMSRA european/regional reanalysis data and i want to know how to convert the surface PM10 Composite from unit ug / m3 \* ug / m3 to mass concentration of PM10 w… --- ## [CAMS Surface concentration of a given species](https://forum.ecmwf.int/t/cams-surface-concentration-of-a-given-species/1181)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 1\ **Last updated:** [31 October 2020 23:16 UTC](https://forum.ecmwf.int/t/cams-surface-concentration-of-a-given-species/1181 "2020-10-31T23:16:56Z")
Users who want get the surface concentration of a CAMS given species, should be taking the mixing ratio (kg per kg dry air) on the lowest model level (L60 or L137, depending on the dataset) and multiplying by the dry air… --- ## [Why is the air quality forecasts showing differently from one provider to another?](https://forum.ecmwf.int/t/why-is-the-air-quality-forecasts-showing-differently-from-one-provider-to-another/1547)
**Author:** [@Anabelle](https://forum.ecmwf.int/u/Anabelle)\ **Replies:** 0\ **Last updated:** [12 October 2020 11:43 UTC](https://forum.ecmwf.int/t/why-is-the-air-quality-forecasts-showing-differently-from-one-provider-to-another/1547 "2020-10-12T11:43:02Z")
Air quality forecasts as provided by different providers can create some confusion. It is important to understand what they actually indicate. Forecasts of air quality are very similar to your daily weather forecast. We… --- ## [Dust emissions are too high in Cycle 46r1](https://forum.ecmwf.int/t/dust-emissions-are-too-high-in-cycle-46r1/1057)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [6 July 2020 11:29 UTC](https://forum.ecmwf.int/t/dust-emissions-are-too-high-in-cycle-46r1/1057 "2020-07-06T11:29:19Z")
The dust emissions of CAMS Near Real Time forecast and analysis have too high values. This is a know issue of Cycle 46r1 and an unfortunate result of the new dust emissions scheme, which just happened to be implemented i… --- ## [Why are the CAMS forecasts sometimes showing poor air quality (high values of air quality index), while we are in lockdown?](https://forum.ecmwf.int/t/why-are-the-cams-forecasts-sometimes-showing-poor-air-quality-high-values-of-air-quality-index-while-we-are-in-lockdown/1546)
**Author:** [@Anabelle](https://forum.ecmwf.int/u/Anabelle)\ **Replies:** 0\ **Last updated:** [30 April 2020 11:23 UTC](https://forum.ecmwf.int/t/why-are-the-cams-forecasts-sometimes-showing-poor-air-quality-high-values-of-air-quality-index-while-we-are-in-lockdown/1546 "2020-04-30T11:23:20Z")
The quality of the air at any location is determined by many factors and the effects of restrictions and lockdown measures are more complex than it may seem. Firstly, levels of atmospheric pollution are driven by emissi… --- ## [European Air Quality information in support of the COVID-19 crisis FAQs](https://forum.ecmwf.int/t/european-air-quality-information-in-support-of-the-covid-19-crisis-faqs/1543)
**Author:** [@Anabelle](https://forum.ecmwf.int/u/Anabelle)\ **Replies:** 0\ **Last updated:** [29 April 2020 16:28 UTC](https://forum.ecmwf.int/t/european-air-quality-information-in-support-of-the-covid-19-crisis-faqs/1543 "2020-04-29T16:28:06Z")
If you have questions about CAMS European air quality products in support to the COVID-19 crisis (e.g. How are the COVID-19 restrictions and lockdown measures expected to affect air quality?, etc) , please check the CAMS… --- ## [Representations of SO2 and SO4 in CAMS reanalysis](https://forum.ecmwf.int/t/representations-of-so2-and-so4-in-cams-reanalysis/1545)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [28 April 2020 11:04 UTC](https://forum.ecmwf.int/t/representations-of-so2-and-so4-in-cams-reanalysis/1545 "2020-04-28T11:04:09Z")
Before the Implementation of IFS cycle 46r1, there were two separate CAMS Global archived analysis and forecast daily representations of SO2 and SO4: one as part of the aerosol scheme, and one as part of the gas-phase ch… --- ## [Q&A - wildfires](https://forum.ecmwf.int/t/q-a-wildfires/1544)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [13 March 2020 12:16 UTC](https://forum.ecmwf.int/t/q-a-wildfires/1544 "2020-03-13T12:16:15Z")
Discover some interesting information about wildfires and the CAMS Global Fire Assimilation System (GFAS). Here the link: https://atmosphere.copernicus.eu/qa-wildfires --- ## [Preparing of CAMS for WRF-Chem - help](https://forum.ecmwf.int/t/preparing-of-cams-for-wrf-chem-help/1085)
**Author:** [@Joana\_Medeiros](https://forum.ecmwf.int/u/Joana_Medeiros)\ **Replies:** 3\ **Last updated:** [5 March 2020 15:27 UTC](https://forum.ecmwf.int/t/preparing-of-cams-for-wrf-chem-help/1085 "2020-03-05T15:27:52Z")
Dear all, I wrote this topic before, but I haven't got any replies yet, I am not sure if I am posting this the right way, but here it goes again : I just downloaded CAMS data for the year 2017 for a simulation with WR… --- ## [Daily CAMS Greenhouse Gas (GHG) global analyses and forecasts from ECMWF](https://forum.ecmwf.int/t/daily-cams-greenhouse-gas-ghg-global-analyses-and-forecasts-from-ecmwf/1202)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [2 December 2019 12:20 UTC](https://forum.ecmwf.int/t/daily-cams-greenhouse-gas-ghg-global-analyses-and-forecasts-from-ecmwf/1202 "2019-12-02T12:20:39Z")
This is only affecting users who have a MARS privilege account. The forecasting system was updated to the latest version of the ECMWF Integrated Forecasting System (IFS), CY46R1. Here the list of major cha… --- ## [Differences between air quality forecast on my phone and direct air quality monitoring stations](https://forum.ecmwf.int/t/differences-between-air-quality-forecast-on-my-phone-and-direct-air-quality-monitoring-stations/1345)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [14 November 2019 15:05 UTC](https://forum.ecmwf.int/t/differences-between-air-quality-forecast-on-my-phone-and-direct-air-quality-monitoring-stations/1345 "2019-11-14T15:05:45Z")
The Copernicus Atmosphere Monitoring Service explains in the following video the reasons behind the differences between air quality forecast and direct air quality station measurements: Why's the air quality forecast on… --- ## [Windy.com has implemented new parameters including Fire Radiative Power (FRP)](https://forum.ecmwf.int/t/windy-com-has-implemented-new-parameters-including-fire-radiative-power-frp/1023)
**Author:** [@Xiaobo\_Yang](https://forum.ecmwf.int/u/Xiaobo_Yang)\ **Replies:** 0\ **Last updated:** [31 October 2019 08:55 UTC](https://forum.ecmwf.int/t/windy-com-has-implemented-new-parameters-including-fire-radiative-power-frp/1023 "2019-10-31T08:55:43Z")
https://www.windy.com/-Show-add-more-layers/overlays?fires,-23.601,-54.567,4 Please note that the FRP parameter is visualised in two ways: as a vector - it can be added to Points of Interest bar in the bottom right c… --- ## [How Air Quality Indexes (AQI) are calculated?](https://forum.ecmwf.int/t/how-air-quality-indexes-aqi-are-calculated/1561)
**Author:** [@Anabelle](https://forum.ecmwf.int/u/Anabelle)\ **Replies:** 0\ **Last updated:** [30 October 2019 09:22 UTC](https://forum.ecmwf.int/t/how-air-quality-indexes-aqi-are-calculated/1561 "2019-10-30T09:22:04Z")
CAMS offers data to Euronews and CNN. You will probably be interested in how the indexes are calculated, see links below: Euronews (Not available anymore) CNN --- ## [PM10 and PM25 global products](https://forum.ecmwf.int/t/pm10-and-pm25-global-products/1084)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 2\ **Last updated:** [14 October 2019 10:58 UTC](https://forum.ecmwf.int/t/pm10-and-pm25-global-products/1084 "2019-10-14T10:58:49Z")
How are PM10 and PM25 in CAMS global products calculated? --- ## [CAMS global AOD evaluation versus AERONET observations](https://forum.ecmwf.int/t/cams-global-aod-evaluation-versus-aeronet-observations/1278)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 1\ **Last updated:** [4 October 2019 14:42 UTC](https://forum.ecmwf.int/t/cams-global-aod-evaluation-versus-aeronet-observations/1278 "2019-10-04T14:42:28Z")
Why CAMS global AOD evaluation against AERONET observations differ slightly between the operational validation charts and what's in the quarterly evaluation and quarterly control report? --- ## [CO and other parameters night peak](https://forum.ecmwf.int/t/co-and-other-parameters-night-peak/1542)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 1\ **Last updated:** [4 October 2019 14:41 UTC](https://forum.ecmwf.int/t/co-and-other-parameters-night-peak/1542 "2019-10-04T14:41:06Z")
Why do CO and other parameters peak during the night? --- ## [Reference for media from CAMS website](https://forum.ecmwf.int/t/reference-for-media-from-cams-website/1043)
**Author:** [@Michela](https://forum.ecmwf.int/u/Michela)\ **Replies:** 0\ **Last updated:** [26 September 2019 15:28 UTC](https://forum.ecmwf.int/t/reference-for-media-from-cams-website/1043 "2019-09-26T15:28:28Z")
Media from CAMS website may be used for projects or publications under the condition that the source is acknowledged, in line with the picture, as follows: Credit: ECMWF, Copernicus Atmosphere Monitoring Service (CAMS) … [Previous page](https://forum.ecmwf.int/c/datasets-and-usage/cams-datasets-and-usage/14.md?page=2) [Next page](https://forum.ecmwf.int/c/datasets-and-usage/cams-datasets-and-usage/14.md?page=4)