Data Availability

The WATCH project has produced a large number of data sets which should be of considerable use in regional and global studies of climate and water. Some of these datasets are described in the special collection, particularly Weedon et al. 2011 and Haddeland et al 2011. These data are all hosted by IIASA in Austria on a basic FTP site available to the public. For an introduction to the water cycle with illustrations of decadal averages plus visualisation of available data, see

Included in the data sets are the meteorological data used by global hydrological or land surface models and model outputs for the 20th and 21st Centuries. All the WATCH data is in NetCDF format (Network Common Data Format see NetCDF is an extremely efficient data format for large volumes of data and is becoming popular with modellers as both an input and output format. Data conforms to the ALMA-data exchange convention; for more information, please see We have introduced a web based system to catalogue these data which can be accessed via the CEH Gateway catalogue ( Use the search term WATCH in the gateway site to find a list of the available data.

The data has been developed and/or produced for the purposes of the WATCH project and no warranty is given as to its suitability for use by the user. No liability is accepted by the WATCH project and its members for any errors or omissions in the data or associated information and/or documentation. Use of the data should include acknowledgement of the WATCH project, authors of the data and previously published texts. The appropriate references are included in CEH Gateway catalogue records. Users of the data should consult the citations and instructions as indicated in the “README files” stored with the Data on the IIASA ftp site.

Outline of what is available

  1. WATCH Forcing Data 20th Century: a meteorological forcing dataset (based on ERA-40) for land surface and hydrological models (1901-2001). Five variables are at 6 hourly resolution and five variables are at 3 hourly resolution. View more 
  2. WATCH-Forcing-Data-ERA-Interim: WFDEI was produced post-WATCH using WFD methodology applied to ERA-Interim data. It is a meteorological forcing dataset extending into early 21st C (1979 – 2012). Eight meteorological variables at 3-hourly time steps, and as daily averages. See Read me (pdf) for explanation and access codes
  3. WATCH Driving Data 21st Century: similar to the WATCH forcing data but for the 21st Century and is constructed from model output not interpolated observational data. Two climate scenarios, B1, A2 and a Control were each run through three global climate models (CNRM, ECHAM5 and IPSL) to produce a total of 9 sets of future driving data at 0.5 degree resolution. View more
  4. WATCH 20th Century Model Output Datasets: the WATCH forcing data has been run through nine land surface or global hydrological models, to produce a range of output variables. View more
  5. WATCH 21st Century Model Output: the 21st century WATCH driving data was put through ten land surface and global hydrological models. View more
  6. 20th Century Ensemble Data: ensemble of model output data from 5 models for 4 hydrological variables, stored as daily data in monthly netCDF files
  7. Test Basin data: 21st C driving data for each test basin (Crete, Glomma, Nitra, Upper-Elbe, Upper Guadiana)