A loss of oxygen in global ocean seawater 94 million years ago led to a mass extinction of marine life that lasted for roughly half a million years.
Earth Sciences
Aug 9, 2017
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Oxygen in the seawater is not only vital to most marine organisms, its concentrations also affect the chemistry of the ocean and that of the atmosphere above. In oceanic regions with very little oxygen, for example, large ...
Earth Sciences
Jul 7, 2017
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39
Dramatic drops in oceanic oxygen, which cause mass extinctions of sea life, come to a natural end - but it takes about a million years.
Earth Sciences
May 12, 2017
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346
A new analysis of decades of data on oceans across the globe has revealed that the amount of dissolved oxygen contained in the water - an important measure of ocean health - has been declining for more than 20 years.
Earth Sciences
May 4, 2017
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Though they may seem rock solid, the ancient sedimentary rocks called iron formations - the world's chief economic source of iron ore - were once dissolved in seawater. How did that iron go from a dissolved state to banded ...
Earth Sciences
Apr 10, 2017
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9
Dead zones affect dozens of coral reefs around the world and threaten hundreds more according to a new study by Smithsonian scientists published in Proceedings of the National Academy of Sciences. Watching a massive coral ...
Environment
Mar 20, 2017
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52
Oxygen is an essential necessity of life on land. The same applies for almost all organisms in the ocean. However, the oxygen supply in the oceans is threatened by global warming in two ways: Warmer surface waters take up ...
Earth Sciences
Feb 15, 2017
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Around the world, wide swaths of open ocean are nearly depleted of oxygen. Not quite dead zones, they are "oxygen minimum zones," where a confluence of natural processes has led to extremely low concentrations of oxygen.
Earth Sciences
Dec 19, 2016
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27
Large areas of the global ocean, so called marine "dead zones" contain no oxygen and support microbial processes that remove vast amounts of nitrogen from the global ocean. Nitrogen is a key nutrient for life.
Environment
Dec 5, 2016
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455
Coastal wetlands and ocean sediments are home to unique microbial communities that convert the more potent greenhouse gas methane into carbon dioxide even in the absence of oxygen, which does not penetrate below the top few ...
Environment
Jun 22, 2016
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13
