DOI: 10.13127/nadr_clim_ts_3km.1
title: High resolution climatologies of temperature and salinity of the North Adriatic Sea
title: nadr_clim_ts_3km

description: The EMODNET_NADR_CLIM_TS_V1 product contains Temperature and Salinity climatological fields for the Northern Adriatic Sea. Monthly and seasonal fields are released for periods 1955-2016, 1955-1984 and 1985-2016, while seasonal fields are provided for 6 decades: 1955-1964, 1965-1974, 1985-1994, 1995-2004, 2005-2016. The climatological fields were obtained from an integrated dataset in the Northern Adriatic Sea which combines data extracted from SeaDataNet infrastructure and the Coriolis Ocean Dataset for Reanalysis (CORA5.2). The analysis was performed with the DIVAnd (Data-Interpolating Variational Analysis in n dimensions), version 2.6.1. The horizontal resolution of the grid  is 3km
description: Data composing the merged SDN-CORA5.2 data set were quality controlled following the consolidated guidelines defined in the framework of the SeaDataNet2 Project and further refined in SeaDataCloud, as described in Simoncelli et al. (2020b). Additional QC analysis through the software ODV has been performed on the CORA5.2 data subset in order to discard data anomalies (outliers, stations on land, wrong spatial or temporal location). After the QC analysis the duplicates were removed from the merged data set and the interpolation of temperature and salinity profiles on the WOA18 standard levels was performed. Data have been linearly interpolated at the WOA18 standard depth and extrapolation was applied to the surface and bottom fields.
Salinity lower than 16 PSUs were discarded to avoid too strong of coastal gradients.
The land-sea mask needed for the calculation of the climatologies was produced from the GEBCO_2019 bathymetry, masking some isolated grid cells in the analysis levels and manually adjusting some features for the Croatian islands. Also the Venice and Marano lagoons have been masked out in order to avoid spurious effects in the climatological products due to their peculiar morphological characteristics.
The background field was defined to obtain large scale spatial trend fields using a large horizontal correlation length equal to 2 degrees. Salinity background is annual, while temperature background is monthly, computed considering a sliding three-month window.
Three background fields having different time coverages have been used to run the analyses:
1.	1955-2016 background field for the 1955-2016 analysis
2.	1955-1984 background field for 1955-1984, 1955-1964, 1965-1974 and 1975-1984 analyses;
3.	1985-2016 background field for 1985-2016, 1985-1994, 1995-2004 and 2005-2016 analyses.
A thourough tuning of correlation length (L) and epsilon2 parameters was performed in order to find a robust balance between the minimization of residuals and the smoothness of the climatological fields produced. The adopted values of the correlation length were 0.5 degrees for the analysis and 2 degrees for the background field estimation. Those used for epsilon2 were 1 for the analysis and 12 for the background field estimation. Both correlation length (L) and epsilon2 parameters have been set constant for all the vertical levels considered.
A consistency analysis with respect to the most consolidated lower resolution climatologies was also performed.