The department of Clima Maritimo (CM) belongs to the "Ente Publico Puertos del Estado", a public company that carries out the co-ordination and management of 47 harbours constituting the Spanish Harbour System. CM is a department of research and development within the field of physical oceanography. The activities of CM are divided in four main areas:

- Control and Management of the Measuring Networks of Puertos del Estado: scalar and directional wave data, sea level, radar data, and coastal meteorological data.
- Support and development of an Oceanographic Database: contains information from different sources as measuring networks, numerical models and statistical analysis, etc. Some data are generated at CM and other by purchase or exchange with different institutes.
- Development of Numerical Wave and Ocean circulation Models.
- Operational forecast: waves, currents and sea level area forecasted for the Spanish harbours on a twice a day cycle.

CM has a wide experience in circulation modeling. The HAMSOM model, developed by the Institute fur Meereskunde and by Clima Marítimo, has been applied in wide range of temporal and spatial scales, has been used inside the ECAWOM model and is being used, since 1998, on a operative sea level forecasting system for the Spanish waters developed at Clima Marítimo.

The WAM model cycle 4 is run operationally by CM since 1995 to provide with a wave forecast to the Spanish Harbours. CM was also involved in the work carried out to implement the model at the European Centre for Medium Range Weather Forecast as the operational model of the Centre. Several modifications have been introduced in the code to adapt it to the Spanish coastal waters and to improve its performance. The output is regularly verified against the Spanish buoy network.

A database containing all the measured data from the Spanish network of tidal gauges and oceanographic buoys was developed and is maintained by CM. Data is subjected to a quality control process and stored daily. Numerical data from CM's operational forecast systems is also stored in the data base. Mean and extreme analysis for selected points is regularly carried out by requirement of the users and extreme and mean atlas are regularly issued.