Global Warming: The Mount Merapi Eruption and Climate Change

News out of Indonesia is that its most active volcano, Mount Merapi has erupted again. Here’s a link to learn more about the volcano.

And since we’ve been writing on global warming a lot recently, its worth also pointing out the effect that volcanic eruptions have on climate change. According to an article from 2002 in the Seattle Times:

  • Mount St. Helens has been known to pump out between 50 and 250 tons a day of sulfur dioxide, at the time the article was written, the volcano was the state’s number one polluter!
  • The 1991 eruption of Mount Pinatubo in the Philippines blew out so much of the gas that the resulting haze spread around the globe and lowered average surface temperatures in the Northern Hemisphere by nearly one degree.
  • So, volcanos play a significant role in climate change…more than we think. Global climate change isn’t just made made.

  • Worldwide, sulfur dioxide emissions from volcanoes add up to about 15 million tons a year.
  • In other words, as US Geological Survey Scientist Terry Gerlach notes, “You can’t call [volcanic eruptions] trivial, compared with human activity.”

  • Join the discussion 9 Comments

    • Wadard says:

      I dunno … it seems like you and your ilk are going to take the slightest anomaly (or apparent-to-you-only anomaly) and use that to conclusively skewer the entire science of global warming and thus continue business as usual.

      I am sorry – that is not old fashioned ignorance but complete and utter denialism. Or a serious lack of intelligence. Or it displays your clear lack of an education in didactic rationalism.

    • Earl E Riser says:

      As we learned from the movie THE MATRIX, humans are the smartest parasite ever to have evolved on planet Earth. We are already recognizing our effect on the host and are preparing to develop technologies to lock in the benefits of our society and expel the old crumbling technologies that threaten our very existence.
      Be proud that we have an educated voice, that listen when we need to, and act when we have to.

    • TokyoTom says:

      Blogger’s Apprentice, thanks for another opportunity to help clear the air.

      As I imagine you know, the mixed effects of volcanoes (SO2 and particulates) on climate are well known and have been studied intensively, especially after the 1991 eruption of Mount Pinatubo in the Philippines. This information has validated the climate change models that tell us we should worry about anthropogenic GHGs and their reinforcement from higher levels of water vapor and releases of methane from thawing tundra and rotting vegetation.

      Yes, volcanoes will always play a role in climate, but it is clear that human GHGs are overwhelming their effects.

      More useful information on the role of volcaones is at NASA’s Earth Observatory:


      “Research into the worldwide climatic impact of the 1991 Mount Pinatubo volcanic eruption during the 10 years since the eruption has strengthened the case for human causes of global warming, a Rutgers scientist reports in a paper published in the February 14 issue of the international journal, Science.

      “The Pinatubo research also has improved scientists’ ability to forecast the impact of future volcanoes on weather and climate, says the paper’s author, Alan Robock of the university’s Center for Environmental Prediction in the Department of Environmental Sciences, Cook College.

      “According to Robock, the eruption on Luzon Island in the Philippines on June 15, 1991 produced the largest volcanic cloud of the 20th century and caused changes in worldwide climate and weather that were felt for years.

      “The changes wrought by Pinatubo’s sulfuric acid cloud, which blocked a large percentage of sunlight from reaching the earth, initially included cooler summers and warmer winters, an overall net cooling at the earth’s surface and altered winds and weather patterns, Robock said.
      In certain areas such as the Middle East, it produced a rare snowstorm in Jerusalem and led to the death of coral at the bottom of the Red Sea, he noted.

      “The cloud also caused depletion of the ozone layer over Temperate Zone regions of the Northern Hemisphere where much of the world’s population resides, in addition to the regular ozone “hole” which appears in October over Antarctica, the researcher said.

      “Most significant, the scientist said, Pinatubo helped validate computer-generated climate models that demonstrate human-caused global warming.
      Using computer modeling, said Robock, scientists have been able to account for natural warming and cooling, as found in Arctic and Antarctic ice core samples and tree rings covering hundreds of years up to the last century.
      “If you plug in volcanic eruptions, El Ni、os, solar variations and other natural causes and try to simulate past climate changes, you can do a pretty good job of modeling climate change until the end of the 19th Century,” the researcher said.

      “After that period, he said, natural causes alone don’t account for the amount of warming, about 0.6 degrees Celsius (1.1 degrees Fahrenheit), that has taken place in the last century.
      “But when you factor in Pinatubo and other eruptions along with anthropogenic (human-caused) emissions,” said the scientist, “it accounts for the observed record of climate change for the past century, including the overall warming and episodic cooling, and validates the climate models.”

      As Paul notes, change has always been occurring; however, now most of it is not natural and far from being on an even keel, we are definitely rocking the boat. One would think that manufacturers would want greater long-term certainty over climate, but then I realize that manufacturers must be enjoying the free ride they get from all of use by not having to bear any expense to their free use of the atomosphere for CO2 releases.



    • Robbie says:

      According to the IPCC sulfur dioxide is not a greenhouse gas. The particulates from teh volcano will have a cooling effect, but there will be no warming effect – i.e. the volcano will delay the progression of global warming

    • Wadard says:

      Yes your logic is a bit shaky apprentice – volcanic activity and other natural events including solar flaring has all been affecting the climate forever. That is not in dispute. What is disputed by the so called ‘skeptics’ is that the additional co2 put into the atmosphere by man-made global warming is ‘tipping the balance’ in favour of a rate of warming that the biosphere will not be able to keep up with.

      I know it is not a simplistic argument but try to keep up.

    • John Bamforth says:

      You’re on the right track, dicussing Volcanic effects on climate change. The eruption of Tambora in Sumatra in 1815 caused the “Year without a summer” in 1816. It snowed in July in New England that year. The climate of the following three years resulted in food shortages across Europe with food riots taking place. Political change followed this in France.
      To say that we have done “just fine” for the last 4 billion years however, is not realistic. There have been five mass extinctions throughout Earth’s history, with all of them attributed to climate change. The exact causes of each of those climate changes is less certain however. Whether the changes were caused by volcanos or asteroids is uncertain. We do know that the eruption of Toba 74,000 years ago,(also in Sumatra) caused the extinction of 95% of all life on Earth. The crater, or more accurately the caldera of Toba is 75 miles long and 34 miles wide.

    • we didn’t necessarily say that volcanic activity affects global warming…in fact quite the opposite. VOlcanic activity is affecting climate change…yes, you are right, we’ve been doing just fine for 4 billion years, cooling and warming…as you say. cheers.

    • Paul Kalyn says:

      To link volcanic activity to climate change is a no-brainer. But to say it is a problem affecting global warming is ridiculous, because volcanic activity has been happening on this Earth for 4 billion years….and we’re doing just fine. The Earth has and always will have cycles, warm or cold. Such eruptions are just one way of keeping the planet on an even, balanced keel; change is always occurring.

    • Rosemary Mosco says:

      True, but studies have shown the cooling effect of volcanoes has been diminishing over time as our gas output overwhelms their output. Not trivial, certainly, but we’re overtaking their influence. A scary thought.