Reply #3: "Small ocean changes can also influence volcanic eruptions,"

[Junkdrawer]

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Small ocean changes can also influence volcanic eruptions, says David Pyle of the University of Oxford. His study of eruptions over the past 300 years with Ben Mason of the University of Cambridge and colleagues reveals that volcanism varies with the seasons. The team found that there are around 20 per cent more eruptions worldwide during the northern hemisphere's winter than the summer (Journal of Geophysical Research, DOI: 10.1029/2002JB002293). The reason may be that global sea level drops slightly during the northern hemisphere's winter. Because there is more land in the northern hemisphere, more water is locked up as ice and snow on land than during the southern hemisphere's winter.

The vast majority of the world's most active volcanoes are within a few tens of kilometres of the coast (see map). This suggests the seasonal removal of some of the ocean's weight at continental margins as sea level drops could be triggering eruptions around the world, says Pyle.

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http://www.newscientist.com/article/mg20327273.800-climate-change-may-trigger-earthquakes-and-volcanoes.html?full=true