ENES and ESGF
The Earth System Grid Federation (ESGF) offers access to more than two Petabytes of climate data, for example the complete set of CMIP5 data (global climate model simulations) and most CORDEX data (regional climate model simulations). IS-ENES operates the European part of ESGF.
The image above shows the state of the Grid with 17 portals and more than 45 data nodes worldwide in June 2015 before the ESGF overhaul. After the overhaul, ESGF went up with less portals due to practical reasons. Additionally, many of the smaller nodes are still down after the ESGF overhaul. Nevertheless, data nodes of all delineated partner institutions will come back in the course of time.
Users should visit one of the portals. ESGF portals offer search in the metadata, registration and data download free of charge. Anonymous search is possible. For data download you need an account.