Trends in chlorophyll-a concentrations in European seas (1980-2021)

More information

• Temporal trends were estimated with the non-parametric Mann-Kendall test. Only stations having data of at least 5 years and having at least data in the last 5-year period (2017-2021) were considered. A p-value <0.05 was used to consider a statistically significant trend.
• Results reflect data availability, which may vary significantly across regions and over time.

 Temporal coverage
1980-2021 (the temporal range specified is the maximum range of dates for raw observations but this range varies upon the availability of observations at each location).

Methodology
Based on datasets produced for the CSI023_MAR006_Chlorophyll in transitional, coastal and marine waters in Europe_2023 Indicator, the number of locations with significant decreasing trends (green), increasing trends (orange) and no trends (grey) was counted for each marine region and all regions combined, and these values were plotted in a bar-type chart.