You look at the actual article, it blames something DIFFERENT.
The data from this station also follows how the Baltic Sea slowly began to lose oxygen (hypoxia) near its sea floor thanks to the large-scale dumping of agricultural fertilizers and sewage into the sea.
Water pollution may be a problem there, but alleged and/or real global warming didn’t do it.
My thoughts exactly. Agricultural pollutants. There’s no way for them to become diluted.
I “suggest” the pollution in the Baltic Sea “could be” the cause of global, er, climate, er, what is it called now?