Scientists have been debating whether or not mantle plume heat contributes to western Antarctica’s instability. Some recent studies provided evidence this might be the case, but even this study’s authors were skeptical. “I thought it was crazy,” Hélène Seroussi, the study’s co-author and scientist at NASA’s Jet Propulsion Laboratory, said in a release. “I didn’t see how we could have that amount of heat and still have ice on top of it,” Seroussi said in a statement. NASA says Seroussi’s study provides more evidence of geothermal activity underneath a portion of the world’s largest ice sheet.
Because Agung is located near the equator, a major eruption with ash flying up into the stratosphere would have short-term climatic impacts that could last a few years. Agung last erupted in 1963 with an explosivity index of VEI 5, sending a plume of ash some 25 km into the atmosphere before leading to a cooling of 0.5°C. The eruption of Pinatubo in the Philippines in 1991 led to a global cooling of 0.5°C.
A survey of the region of the West Antarctic Rift System has revealed 91 new volcanoes hidden within the ice. The new volcanoes are on top of the 47 whose peaks are above the ice and were already known about. The volcanoes range in height from 100m to a towering 3,850m tall. Geologists say the range has similarities to east Africa’s volcanic ridge, which was previously thought to have the densest concentration of volcanoes in the world.
'After taking out the effect of ENSO and eruptions, it is apparent that temperatures have been flat since the early 1990’s; indeed they have arguably been falling since. This is significant. We are often told that the 17-year pause, with which we are all familiar, is solely dependent on cherry picking the big El Nino year of 1998 as a starting point. What Santer’s study shows is that there has been no underlying upward trend in global temperatures for more than 20 years.'