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Environmental information systems
Trends in chlorophyll-a concentrations in Europe's seas (1980-2021)
Chart (static)
Notes:
The chart shows the number of times series-locations with statistically significant: (1) no trend (grey), (2) decreasing trend (green) and (3) increasing trend (orange) by marine region. The different marine regions are presented by one bar each and combined for Europe's seas.
Trends not available for the North-East Atlantic Ocean and Macaronesia regions due to insufficient time-series data.
• IBI* = Bay of Biscay and the Iberian Coast
Downloads
Data sources
Metadata
More info
- Oceanographic database, International Council for the Exploration of the Sea (ICES)
- Chemistry data - Data & products on marine water quality, European Marine Observation and Data Network (EMODnet)
- Waterbase - Water Quality ICM, 2022, European Environment Agency (EEA)
- Baltic Sea
- Bay of Biscay
- Black Sea
- Celtic Seas
- Greater North Sea
- Iberian Coast
- Macaronesia
- Mediterranean Sea
- North-East Atlantic Ocean
1980-2021
• 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.