Which way to access data

The EFAS archive contains the operational output of EFAS as well as the modelled climatology. For more information of the model setup we refer to The data download provides access to the raw hydrological model output. There are different ways of accessing the data, and which way you choose is depending on the purpose of using the data.

  1. Access to the MARS archive. Here the user can select which part of the data that they would like to download in terms of area, dates, forcing model, timestep, variables etc. The MARS archive offers a huge flexibility for the user, however it requires some basic programming skills to retrieve the data. It is therefore envisioned that the MARS access option will be used by a smaller subset of users. To access the data the users need to register. This is also necessary since the real-time EFAS data is not open to the public. ACCESS through MARS is mostly for operational data and
  2. Access through Copernicus Climate Data Store. The data that are open to the public are also accessible through the CDS. Here the users can select which parameters and which dates they want to download. It is not as flexible as MARS in terms of selecting the output, but it is more user-friendly. The CDS is designed to browse different data and download already predefined datasets. Further, the user can perform simple calculations and visualizations of the data through the toolboxes. The functionality is still under development, but it is foreseen that the users on the future will be able to perform many modifications of the data and access the information in a desired format. However, these tool need to be developed, and this was not part of the current specific contract.

Meteorological Archival and Retrieval System (MARS)

MARS is the main repository of meteorological data at ECMWF. It contains petabytes of operational and research data, as well as data from Special Projects. Read the MARS documentation for more information.

Users can browse the Archive catalogue (describing archive data that ECMWF can distribute) or the complete MARS catalogue (authorization required) from our dedicated server.

To access the data through the MARS archive you need to be a registered user at ECMWF. To create an account, please send an email to

If you are a registered user for ECMWF products, you will find the Copernicus EFAS data here:

Copernicus Climate Data Store

The CDS is an easy-access archive for all kinds of climate data. All archived EFAS data is made available as raw output. You will also be able to manipulate the data using the toolbox to retrieve the specific information you need.

Attention: Access to EFAS real-time products is currently restricted to EFAS partners only. EFAS archived products (forecasts older than one month) are freely accessible. EFAS products are subject to the Copernicus Emergency Management Service – flood early warning and monitoring systems Terms and conditions.