Storm Johannes Pushed Oxygen-Free Water Into Baltic Sea Coastal Shallows
A storm named Johannes, which hit Estonia late last year, caused a rare phenomenon in the Baltic Sea. Oxygen-free water rose from a depth of 90 metres and flooded into shallow areas. Scientists have documented this for the first time.
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Storm Johannes, which struck Estonia at the end of last year, caused a rare and dangerous phenomenon in the Baltic Sea. Water without oxygen, which had been sitting in the sea's depths for decades, rose from a depth of about 90 metres and surged into shallow coastal waters. This is the first such case that scientists have documented in the Baltic Sea.
Why it is dangerous
For coastal ecosystems, this water meant a death trap. That is why it is called "dead water". Organisms living in the shallows cannot survive without oxygen.
An event that almost went unnoticed
The disaster initially went almost unnoticed. Now that the phenomenon has been documented, researchers can study it. The source gives no details on how much damage it caused, so this article does not address that question.
