A Dataset of Monthly Suspended Particulate Matter (SPM) Concentrations and Associated Temporal Decomposition and Trend Analysis in European and Mediterranean Coastal Waters from 2016 to 2025

This dataset provides monthly Suspended Particulate Matter (SPM) concentrations derived from Sentinel-3 Ocean and Land Colour Instrument (OLCI) observations over European and Mediterranean coastal waters for the period 2016 to 2025, at 300 m spatial resolution. The dataset is related to the article “Recent Changes and Variability of Suspended Particulate Matter in European and Mediterranean Coastal Waters inferred from OLCI data” (Subirade et al. 2026, in press).
SPM was estimated from Copernicus Marine Service (CMEMS) Level-3 reflectance products using the semi-analytical algorithm of Han et al. (2016). Monthly composites were computed using a geometric mean after removal of outliers based on a climatological three-standard-deviation threshold, combined with a sea ice masking procedure in the Baltic Sea. These monthly SPM fields constitute the primary component of the dataset and provide a consistent, high-resolution description of SPM variability across European coastal environments. They are suitable for a wide range of applications, including the study of coastal sediment dynamics, environmental monitoring, and the assessment of spatial and temporal variability of water quality in marine systems.
Building upon these monthly products, the dataset also includes derived variables describing the temporal dynamics of SPM. These products were generated in the framework of Subirade et al. (2026), and include spatial maps of variance partitioning obtained from X11 time series decomposition, separating seasonal, interannual (trend-cycle), and residual components of temporal variability. In addition, long-term trends were estimated using a seasonal Mann-Kendall test and Sen’s slope, expressed as percentage change per year, together with associated p-values. These derived products enable the identification of dominant temporal processes and the detection of statistically significant trends in SPM across European and Mediterranean coastal waters, supporting the analysis of natural variability and anthropogenic influences on coastal systems.
A detailed description of the data processing, methods, and analysis is provided in Subirade et al. (2026), in press. Uncertainties may increase in low-turbidity waters, and residual artefacts may persist in regions affected by sea ice.