Habitat-layer specific spatio-temporal trends of physical and biogeochemical variables in the Black Sea over the past three decades

This dataset contains grid-based trend estimates and seasonal-trend decomposition outputs derived from CMEMS Black Sea reanalysis products for the period January 1993 to December 2023. The dataset includes physical and biogeochemical variables: Temperature Absolute Salinity Dissolved Oxygen pH Net Primary Production (NPP) Mixed Layer Depth (MLD) Temperature, Salinity, Oxygen, pH, and NPP are provided separately for: Pelagic layer (dynamically defined by MLD for each grid cell) Demersal layer (bottom-most grid cell within 0–150 m depth range) MLD is provided as a single-layer variable. All trend calculations were performed at the grid-cell level using the Mann–Kendall test for trend significance and Sen’s slope for magnitude estimation (α = 0.05). Seasonal-Trend decomposition using Loess (STL) was applied to monthly time series prior to trend estimation. For each variable, the NetCDF files contain: Annual Sen’s slope (grid-based trend map) Absolute 95% confidence interval values STL trend component (3D: lon × lat × time) STL seasonal component (3D: lon × lat × time)