Temperature, salinity and chlorophyll nearshore measurements on business days at A Coruña, Galicia (IEO-CSIC), 1996-2025 (Caldeiro Station)

The Oceanographic Centre of A Coruña (IEO-CSIC) has maintained a time series of coastal near-surface variables (surface temperature, salinity and chlorophyll) on business days since 1996. This time series captures annual, seasonal and day to day variability in a nearshore area close to the A Coruña Oceanographic Center. The site is located in Galicia (NW Spain) in a temperate area influenced by seasonal upwelling, where IEO A Coruña maintains sustained ocean observations since the late 1980s as part of the RADIALES project, financed by IEO-CSIC with complementary funding from Xunta de Galicia (GAIN) and recently EMFAF. Temperature and salinity were measured by portable sensors, and chlorophyll concentration was analysed in the IEO A Coruña laboratory by fluorometry using acetonic extracts of seston samples (see methodology in Bode et al. 2019). Chlorophylls a, b and c have been measured since 2000 and earlier measurements of chlorophyll-a were adjusted to ensure the coherence of the series. 
In the framework of the Interreg POCTEP CAPTA project (0062_CAPTA_1_E), this time series has been re-analysed and revised. In addition, automatic quality flags were assigned following the seadatanet.org standard procedures. As additional controls, temperature data are compared to a SBE56 sensor moored at the sampling site in November 2022 with funding of the Spanish MFSD monitoring program (descriptor 7). Salinity and chlorophyll measurements are routinely compared to the surface measurements at the stations of the Radial A Coruña: coastal station 4 (sampled monthly) and shelf station 2 (sampled weekly), as well as to the underway measurements (TSG and fluorometer) of the RV Lura (DOI: 10.17882/110118) near the sampling point to qualitatively detect drifts or biases.
The sampling station is located in A Coruña harbour near the Oceanographic Centre of A Coruña. The location of the sampling site varied according to the historical access to the sea: 
site Latitude Longitude start date end date P1 43.369222 -8.388182 02/09/1996 31/08/2007 P2 43.368678 -8.385817 03/09/2007 11/10/2016 P3 43.368552 -8.387619 13/10/2016 on going
This dataset is catalogued in the NODC IEO-CSIC GeoNetwork where different web services for data access are available.
Following quality control, datasets were formatted in accordance with the MEDAR/Medatlas standard. Monthly files (1996–2025) were then generated using SeaDataNet standard vocabularies to ensure interoperability and compliance with international data-management practices.