The Spanish Institute of Oceanography (IEO-CSIC) and the Jaume Ferrer Research Station (IEO-CSIC, GOIB) maintains a mooring to record temperature data at different depths along the coastal area of Isla de Porros, within the boundaries of the North Minorca Marine Reserve (40º05.49'N, 004º04.43'E); Balearic Islands, Western Mediterranean). This time series mooring is funded since its beginning in 2014 by the General Direction of Universities and Research within the Balearic Islands Government (GOIB). The collected data provides high-resolution temporal data on seasonal temperatures, stratification dynamics and detection of extreme events. The data also contributes to the T-MED-NET network (http://www.t-mednet.org) for the monitoring of climate change effects in marine coastal ecosystems of the Mediterranean Sea, such as mortality events related to heatwaves or distribution of endemic and non-native species.

Assessing the effects of climate change on coastal ecosystems requires long-term monitoring of essential climate-related variables, including the oceanographic thermal regime. The temperature mooring system uses in situ temperature sensors (HOBOS Pro v2) that record hourly data at 5, 10, 15, 20, 25, 30, 40 meters depth. Sensors are setup and recovered by scuba divers twice a year, generally in spring and autumn. The current length of the historical series has allowed for careful quality control to correct potential sensor failures and drifts, as well as the systematic assignment of quality flags that add value to the timeseries. Additionally, the adoption of standard formats and vocabularies recognized at the European and international level facilitates the reuse of these data in different contexts. Data are provided in SDN-Medar/MedAtlas format monthly files.