Versions Compared

Old Version 21

changes.mady.by.user Michela Giusti

Saved on

compared with

New Version 22

changes.mady.by.user Michela Giusti

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Table 2 Summary of the number of fields limits, as well as the major features of all ADS datasets (last reviewed on 16 September 2021)

DatasetNumber of fields limitVolume size limit

Adaptor

(indicates where the data are stored; see "Efficiency Tips" below)

Notes

CAMS global atmospheric composition forecasts

10000175 GB for GRIB files, 30 GB for netCDF filesMARS Internal/external

Those variables listed as fast-access are readily available from ADS disks.

Those variables listed as slow-access and data older than 30 days are stored in ECMWF MARS tape archive.

CAMS global reanalysis (EAC4)

100000175 GB for GRIB files, 30 GB for netCDF filesMARS Internal/external

Those variables listed as fast-access are readily available from ADS disks.

Those variables listed as slow-access are stored in ECMWF MARS tape archive.

CAMS global reanalysis (EAC4) monthly averaged fields

100000175 GB for GRIB files, 30 GB for netCDF filesMARS InternalN/A

CAMS global inversion-optimised greenhouse gas fluxes and concentrations

500N/Aadaptor.urlStored locally on ADS disks

CAMS global greenhouse gas reanalysis (EGG4)

100000175 GB for GRIB files, 30 GB for netCDF filesMARS external

Data are stored in ECMWF MARS tape archive

CAMS global greenhouse gas reanalysis (EGG4) monthly averaged fields

100000175 GB for GRIB files, 30 GB for netCDF filesMARS externalData are stored in ECMWF MARS tape archive

CAMS solar radiation time-series

10000N/Aadaptor.cams_solar_rad2.retrieveThis data is calculated on demand by a service jointly provided by DLR, Armines, and Transvalor. The ADS forwards requests to this service and returns the data from it.

CAMS European air quality forecasts

5000N/Aadaptor.cams_regional_fc.retrieve

There are three classes of speed at which these requests will be processed:

  1. Surface ensemble stored on ADS disks: fast-access
  2. Recent forecasts and analyses for other models/levels stored by third party: slow-access
  3. All other data are stored in a third party archive system:  access to this data is in general much slower than 1. and 2.

CAMS European air quality reanalyses

1000N/Aadaptor.urlCheck the documentation for data availability

CAMS global emission inventories

1000N/Aadaptor.url2.retrieveN/A

CAMS global radiative forcings

1000N/Aadaptor.url

CAMS global radiative forcing - auxilliary variables

1000N/Aadaptor.url

Efficiency tips

  1. Where the data are actually stored can make a significant difference in the speed at which a request is processed. ADS data hosted in 'MARS internal' is stored on ADS disks, and so is faster to retrieve. The 'MARS external' datasets are stored in the ECMWF MARS (tape) archive, and in this case it is important to request as much data as possible from the same tape file in your ADS request.
  2. It is better to submit small requests rather than very large requests. This will ensure your requests are not given a lower priority in the ADS request queue.
  3. When using the CDS API, it is strongly recommended that users take as a starting point the example API request script shown at the bottom of the ADS web  'Download data' page for the dataset of interest, and use this as the basis for your request.

...