Trends in the frequency of low oxygen concentrations in bottom waters of the Baltic Sea, the Mediterranean and the North Sea.

North Sea (incl. the Skagerrak): Belgium, Denmark, Norway, Sweden Baltic Sea (including the Kattegat): Denmark, Estonia, Finland, Germany, Lithuania, Poland, Sweden Mediterranean Sea: Greece, Italy Results of trend analyses applied to time series for the period 1985-2002 (stations with at least three years data in the period 1995-2002 and at least five years in total) are shown with a bar chart for each sea region.