Registration in ECOMS-UDG is done though the UDG THREDDS Administration Portal ?http://meteo.unican.es/udg-wiki/registration. After registration, users have to request membership in one of the following groups: EUPORIAS, SPECS or NACLIM. Note that these three groups provide access to the same datasets (the common datasets for ECOMS) so membership in more than one group is not recommended. Membership is moderated (by the corresponding project leaders) so registration with an institutional email address is required. The process may take some time (one day on average) and results are always communicated via email.