Depending upon who funded them or the politics of those who wrote the studies, you can find the truth, but you will often find the truth after the bogus politics of the studies, buried, sitting way down at the end . . . .
(Why they’re even there is probably to protect the scientists reputation after the truth becomes more acceptable; the Global Warming lobby is powerful!)
Of course totally discounting any effects of weather change playing into this phenomonen might be an over-reaction, there are changes in the global systems that may contribute.
Noticing that the dead zones often occur near where rivers enter the ocean, . . . . where they’re carrying nutrient-rich runoffs – fertilizers, and pesticides (not to mention a number of other pharmaceuticals) onto the floors of the bays and ocean, ought to have been a dead-giveway to any observer that the profit motive is impacting other industries and life itself.
Local conditions and the relevance of the rivers and seasonal currents has lead many a fisherman to doubt the science and the blaming all upon the concept of Global Warming.
Also revealing is, there have been unintentionally successful recoveries of some dead zones around the world (as in the Black Sea), (especially in areas where these chemicals had become too costly for locals to use) – the formerly nitrogen-rich having dropped 37%, local fisheries are again producing fish and crab.
These fertilizers and pesticides have not only been found to cause death, the sea life’s reproduction, of those who’ve survived has been found to have been impacted negatively, as well; obviously, it’s not an easy task to find a simple solution, which is what the media seeks.
My comments: I’m not totally discounting Global Warming; what I am saying, is that often the truth will be buried near the end of the studies and it’s worthwhile to read the last sections first! I’m not putting the studies here but encourage you to search them out yourselves – especially reading the ends of these studies first.
Once again mankind, especially the scientific mindset, assumes too much and understands the interconnectedness of all global systems, too little!