The Swedish government is funding research into the feasibility of using a wind-turbine driven oxygen pump in the Baltic, following studies carried out last year by the University of Gothenburg, which looked at the effect of pumping oxygen-rich surface water to the bottom of two Swedish fjords.

CNN: Can oxygen pump breathe life into ocean 'dead zone?'

These rock-like objects were the first lifeforms to pump enough oxygen into the sea and atmosphere so that complex lifeforms could develop, helping them become the beautiful, life sustaining waters that we know today.

BBC: Grasping the scale of Earth's oceans

The heart doesn't pump well, the body doesn't get enough oxygen, and it begins to retain fluid, which in turn makes pumping harder.

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