Guest post by Steven Goddard
The Washington Post reports today:
An undersea volcano erupts off the coast of Tonga, tossing clouds of smoke, steam and ash thousands of feet (meters) into the sky above the South Pacific ocean, Tuesday, March 17, 2009. The eruption was at sea about 6 miles (10 kilometers) from the southwest coast of the main island of Tongatapu an area where up to 36 undersea volcanoes are clustered
Besides the unusual feet to meters conversion in the quote above, I found it interesting because the SST maps show a warm anomaly in that region, and extending off to the east. Is that anomaly a result or coincidence?
http://weather.unisys.com/surface/sst_anom.html
How much influence do volcanoes have on local climates?
We know that the Antarctic Peninsula (advertised as the fastest warming place on the planet) is a volcanic chain which has seen recent activity.
Noted Antarctic expert Eric Steig tells us that Volcanoes under the ice can’t affect climate on the surface, 2 miles above! This is indeed true and interesting, because CO2 on the surface reportedly can affect the melting of the basal ice, two miles below.
According to some of the best AGW minds, increases of 0.0001 atmospheric CO2 concentration may be more powerful at affecting localized micro-climates than are 2000 degree volcanoes.
In another volcanically active area, the Gakkel Ridge, which was shown to have eruptions last year, the possibility also exists for localized warming. Here is a schematic of the Gakkel Ridge sea floor:
However in that case there is the claim by oceanographic experts that it is impossible for the sea ice above to be affected due to stratifed water layers and thus making the released heat “unable to communicate” to the surface.
Perhaps that is true, but does that stratification remain in a steady state? And is such an inability to “communicate” heat from the depths a feature of our oceans globally?
“alexandriu doru (09:00:27) :
The mean geothermal flux on earth is 60 mW/m^2;
The mean solar flux on earth is 240W/m^2.
Volcans DO NOT AND CAN NOT influence global warming”
But in reality volcanoes DO AND CAN cause global warming. 65 million years ago when that big space rock smashed into Earth and obliterated 90% of Earth’s lifeforms there was an intense area of volcanism in the Siberian region which rose the Eath’s global average termperature briefly by about 3 degrees Celsius until the ash and gas created from the meteor impact and the volcanism blocked out sufficient amounts of sunlight to cool the Earth through a feedback effect.
More recently, the Pinatubo eruption on the Philippines in 1991 triggered a .5 degrees Celsius cooling of the whole globe for that year. And that eruption had a VEI of 6, 10 times for stuff was thrown out campaired to Mt. St. Helens eruption at 1980 which was a VEI 5 eruption.
If we multiply that over 100 km^2, which is roughly the size of the area of intense volcanism in Siberia 65 mya, then you can have a dramatic cooling of the Earth and lots of volcanic ash and noxious gases thrown into the atmosphere which circulated around the world – more than enough to compound the effects of the meteor impact and nearly sterilize the Earth.
Note: The area of volcanism in Siberia 65 mya was caused by the impact because its the antipital point of the impact. In other words, this is where the shockwaves of the impact met after they travel around the globe after they began their journey from the point of impact of the meteor.