In hot water: Ice Age findings forecast problems

(PhysOrg.com) -- The first comprehensive study of changes in the oxygenation of oceans at the end of the last Ice Age (between about 10 to 20,000 years ago) has implications for the future of our oceans under global warming.

The study, which was co-authored by Eric Galbraith, of McGill's Department of & Planetary Sciences, looked at marine sediment and found that that the dissolved oxygen concentrations in large parts of the oceans changed dramatically during the relatively slow natural climate changes at the end of the last Ice Age. This was at a time when the temperature of surface water around the globe increased by approximately 2 C over a period of 10,000 years. A similar rise in temperature will result from human emissions of heat-trapping gases within the next 100 years, if emissions are not curbed, giving cause for concern.

Most of the animals living in the , from herring to tuna, shrimp to zooplankton, rely on dissolved oxygen to breathe. The amount of oxygen that seawater can soak up from the atmosphere depends on the water temperature at the sea surface. As temperatures at the surface increase, the dissolved oxygen supply below the surface gets used up more quickly. Currently, in about 15 per cent of the oceans - in areas referred to as dead zones - dissolved oxygen concentrations are so low that fish have a hard time breathing at all. The findings from the study show that these dead zones increased significantly at the end of the .

"Given how complex the ocean is, it's been hard to predict how climate change will alter the amount of in water. As a result of this research, we can now say unequivocally that the oxygen content of the ocean is sensitive to climate change, confirming the general cause for concern."

The results of this study were published in Nature Geoscience.


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Citation: In hot water: Ice Age findings forecast problems (2011, December 20) retrieved 20 June 2019 from https://phys.org/news/2011-12-hot-ice-age-problems.html
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Dec 20, 2011
Quote - "Given how complex the ocean is, it's been hard to predict how climate change will alter the amount of dissolved oxygen in water. As a result of this research, we can now say unequivocally that the oxygen content of the ocean is sensitive to climate change, confirming the general cause for concern.

That didn't tell us anything. This "discovery" is conducted by 100 level chemistry student. I greatly appreciate information that helps us better understand our affects on the planet but this study does nothing to confirm anything we didn't already know.

Dec 20, 2011
The Arctic sea will soon be free of ice all summer. This will provide a vast area with very cold water, which the author forgot about.

Dec 20, 2011
implications for the future of our oceans under global warming


CO2-induced global warming has not been observed, although global temperatures have generally increased since the Last Little Ice Age.

See http://judithcurr...pdate-ii


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