As universities around the country go full steam ahead, every pun intended, on warning students about the danger of global warming, the recent volcanic eruptions in Iceland may send already cooling temperatures further south, and not to a warmer place.
“Volcanic eruptions are thought to be responsible for the global cooling that has been observed for a few years after a major eruption,” according to NASA. “The amount and global extent of the cooling depend on the force of the eruption and, possibly, its latitude. When large masses of gases from the eruption reach the stratosphere, they can produce a large, widespread cooling effect. As a prime example, the effects of Mount Pinatubo, which erupted in June 1991, may have lasted a few years, serving to offset temporarily the predicted greenhouse effect.
“As volcanoes erupt, they blast huge clouds into the atmosphere. These clouds are made up of particles and gases, including sulfur dioxide. Millions of tons of sulfur dioxide gas can reach the stratosphere from a major volcano. There, the sulfur dioxide converts to tiny persistent sulfuric acid (sulfate) particles, referred to as aerosols. These sulfate particles reflect energy coming from the sun, thereby preventing the sun’s rays from heating the Earth.
“Global cooling often has been linked with major volcanic eruptions. The year 1816 often has been referred to as “the year without a summer.” It was a time of significant weather-related disruptions in New England and in Western Europe with killing summer frosts in the United States and Canada. These strange phenomena were attributed to a major eruption of the Tambora volcano in 1815 in Indonesia. The volcano threw sulfur dioxide gas into the stratosphere, and the aerosol layer that formed led to brilliant sunsets seen around the world for several years.
“However, there is some confusion about the historical evidence that global cooling may be caused by volcanic emissions. Two recent volcanic eruptions have provided contradictory evidence on this point. Mount Agung in 1963 apparently caused a considerable decrease in temperatures around much of the world, whereas El Chichn in 1982 seemed to have little effect, perhaps because of its different location or because of the El Nino that occurred the same year. El Nino is a Pacific Ocean phenomenon, but it causes worldwide weather variations that may have acted to cancel out the effect of the El Chichn eruption.”
How will self-respecting academics incorporate information on volcanic effects on temperatures into their lessons on climate change? My guess: They will ignore it.
I hope that I’m wrong.
Malcolm A. Kline is the Executive Director of Accuracy in Academia.