CORDEX

cordex_bannertop

Read about the CORDEX Africa Analysis Campaign

Read more about the new CORDEX Empirical Statistical Downscaling ESD activity

The CO-ordinated Regional Downscaling Experiment (CORDEX) was birthed out of an increasing need for detailed, high-resolution regional information regarding future climate. Information at this regional scale is needed by scientists in disciplines that require climate information (e.g. hydrologists), as well as decision- and policy-makers, and by those assessing climate change impacts, adaptation and vulnerability. Although climate change projections must necessarily be undertaken with global models, such models do not have sufficient spatial detail for all applications.

Constraints on available computing resources will always limit model resolution; therefore, various techniques have been developed for ‘downscaling’ global climate projections (and shorter-term climate predictions) and for producing fine-scale regional climate information. These include nested regional climate models, variable resolution global models, global uniform high-resolution time-slice simulations, statistical downscaling, and/or combinations of these methods.

To this end, the CO-ordinated Regional Downscaling Experiment (CORDEX) was initiated. The task of this WCRP-sponsored programme is to organize an internationally coordinated framework to produce an improved generation of regional climate change projection information world-wide for input into impact and adaptation studies within the AR5 timeline and beyond. The major goals of the CORDEX programme are as follows :

  1. Provide a quality-controlled data set of regional scale climate information for the recent historical past and 21st century projections covering the majority of populated land regions on the globe. This information will be generated using both dynamical and statistical downscaling methods to regionalise the output from a number of Global Climate Models (GCM) under varying greenhouse gas concentration scenarios. The CORDEX downscaling activities will be based on the latest set of GCM climate scenarios and predictions produced within the 5th Coupled Model Intercomparison Project (CMIP5) and will downscale 150 years of GCM data from 1951-2100.
  2. Define a common set of regions/domains for downscaling and define a standard set of variables, frequency and format for output and archival at a number of CORDEX data centres.
  3. Coordinate a range of regional climate model simulations for the defined domains, forced by analyses of observations (currently the ERA-Interim reanalysis data) to provide a benchmark framework for model evaluation and assessment.
  4. Encourage and coordinate the development of Regional Analysis and Evaluation Teams to; (i) Evaluate the ensemble of downscaling, (ii) develop a suitable set of regionally-specific metrics for evaluation, (iii) collect suitable observational data to evaluate high-resolution downscaling and (iv) design experiments to investigate the added-value of regional climate downscaling and target future priorities in this research.
  5. Provide support and information to climate impact assessment and adaptation groups interested in utilizing CORDEX RCD material in their research.