Or is it the other way around? Do ice ages trigger underwater volcanic activity? How about global warming?
An increase in underwater volcanic eruptions could play a far greater role in climate change than previously thought, say scientists at Columbia University.
Underwater volcanoes erupt in regular cycles linked to changes in the Earth’s orbit, says Dr Maya Tolstoy, a marine geophysicist at the Lamont-Doherty Earth Observatory at Columbia University. The pulses of activity range from just a couple of weeks to 100,000 years.
Some of those underwater explosions pump out enough red-hot lava to create entirely new islands.
2009 eruption of Hunga Tonga-Hunga Ha’apai. Image credit Tonga NEMO
Volcanic eruptions throw huge amounts of gas into the atmosphere, including carbon dioxide, that (supposedly) increases global warming, explains this article in The Daily Mail.
However, volcanoes also release aerosol gases that are known to reduce global warming by creating a reflective barrier against the sun.
Undersea volcanism surges during ice ages
Studying lava flow maps and seismic data from the Pacific, Atlantic and Arctic oceans, Dr Maya Tolstoy and her colleagues found that undersea volcanism seems to surge during ice ages, producing visible bands of hills.
This surge, she says, is because sea levels drop as water becomes locked up on the land in glaciers. This in turn relieves pressure on the undersea volcanoes and allows them to erupt more often.
But I question Dr Tolstoy’s conclusion.
It’s that cart-before-the-horse thing. I maintain that increased volcanic activity, both above water and below water, leads to ice ages.
The underwater volcanoes heat the water, leading to more evaporation. When that moisture rises into skies being cooled by the above-water volcanoes, snowfall increases. And voila! – a new ice age.
As I put it in Not by Fire but by Ice: “Warmer seas and colder skies . . . a deadly combination.”
The Daily Mail’s headline asks, “Are underwater volcanoes causing global warming?”
http://www.dailymail.co.uk/sciencetech/article-2942510/Are-underwater-volcanoes-causing-global-warming-Oceanic-eruptions-greater-effect-climate-thought.html
See also:
http://iceagenow.info/2015/02/underwater-volcanoes-alter-climate-study-finds/
See also:
http://iceagenow.info/2015/02/arctic-seafloor-afire-lava-spewing-volcanoes/