Dirty Volcanic Eruption In Chile Can Change Climate
May 7, 2008
Elaine Meinel Supkis
A mid-sized volcano in Chile is having a major-sized volcanic event. If it blows off its crown, it can change global weather. It all depends on volume, power of the explosive forces breaking out into the stratosphere and the mass of ejected particulate matter and aerosol gases. We have had several 'cooling off' periods caused by volcanos during my lifetime. And in history, volcanic activity has pushed forwards evolution and has caused mini-ice ages as well as starvation and privations. Indeed, some huge volcanic eruptions have nearly killed off all homo sapiens in Africa long ago. Only about 2,000 humans survived the effects of a major volcano in Sumatra blowing up. Volcanos are the engines of evolution just as meteorites can alter the course of nature.
Chile eruption spurs evacuations
Chaiten volcano in the southern Patagonia region began erupting on Friday for the first time in 450 years.Ash from the volcano has caused disruption in neighbouring Argentina. Sitting on the edge of the South American and Nazca tectonic plates, Chile is in one of the most volcanically-active regions on Earth. Experts say about 20 of its more than 100 active volcanoes are in danger of erupting at any time.
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"Today the volcano is erupting with pyroclastic material [of hot ash and gas] on a different scale," he told Reuters news agency."We... have ordered the immediate precautionary evacuation of all civilians, military and press in Chaiten."
A government vulcanologist warned there could be a big eruption at any time."There could be a major explosion that could collapse the volcano's cone," said Luis Lara of the National Geologic and Mining Service.
Here is the You Tube video of this event:
Notice how wide the volcanic eruption is at its base. This is no narrow hiccup by a volcano releasing pressure. It is wide and deep. The resulting cloud of gases and volcanic dust is very intense. There is no lava or fireworks. This is dark, dark material pouring out. Volcanos that are 'dirty' like this are the ones that have the biggest impact on the weather and thus, on all living things. If a volcano also blows up and this one certainly has the capacity to do this, then the world's temperatures can fall significantly.
Click here for the CNN photos at sunset.
Here are the IRIS maps showing the series of 4+mag earthquakes where the volcano is erupting.
This volcanic event is close to Antarctica and far from the Northern Hemisphere. I checked the weather maps and during this time of year, the prevailing winds are eastwards. This is causing problems for Argentina as the volcano's dust is falling thickly there.
Here is the map of all the many volcanos on the 'leading edge' of South America.
Large red triangles show volcanoes with known or inferred Holocene eruptions; small red triangles mark volcanoes with possible, but uncertain Holocene eruptions or Pleistocene volcanoes with major thermal activity. Yellow triangles distinguish volcanoes of other regions.
When I first bought our little slice of the mountain here in Berlin, it was a splendid year, 1990. The fall was so warm, we joked about global warming turning the place into Virginia weather, not the harsher Northeastern weather. It was so warm, when we staked out the perimeters of the house we planned to build, we had absolutely no fear of the following winter. And we did quite well during it. We had less than 3 feet of snow altogether. And it became warm by the end of March. So I looked forwards to an easy summer, doing serious foundation and basement work on the house.
Then, we saw the news on TV: Mt. Pinatubo blew its stack on the other side of the planet. I ran outside to see if there was the characteristic very high, very white sheet of volcanic dust and there it was! The normally very blue sky was wane and pale. 'The weather is going to change for the worse,' I warned my husband. The sun seemed to dim slightly. We were using solar energy and we could see on the computer's screen the output was dropping.
'This is going to be a problem if the volcano keeps up,' I said. I was worried and decided to get some more kerosene lanterns for fear that we would have reduced solar energy.
The Volcanic Mount Pinatubo Eruption of 1991 that Cooled the Planet
Aug 5 2007
In June 1991, the second largest volcanic eruption of the twentieth century* took place on the island of Luzon in the Philippines, a mere 90 kilometers (55 miles) northwest of the capital city Manila. Up to 800 people were killed and 100,000 became homeless following the Mount Pinatubo eruption, which climaxed with nine hours of eruption on June 15, 1991. On June 15, millions of tons of sulfur dioxide were discharged into the atmosphere, resulting in a decrease in the temperature worldwide over the next few years.
*snip*
In addition to the ash, Mount Pinatubo ejected between 15 and 30 million tons of sulfur dioxide gas. Sulfur dioxide in the atmosphere mixes with water and oxygen in the atmosphere to become sulfuric acid, which in turn triggers ozone depletion. Over 90% of the material released from the volcano was ejected during the nine hour eruption of June 15.The eruption plume of Mount Pinatubo's various gases and ash reached high into the atmosphere within two hours of the eruption, attaining an altitude of 34 km (21 miles) high and over 400 km (250 miles) wide. This eruption was the largest disturbance of the stratosphere since the eruption of Krakatau in 1883 (but ten times larger than Mount St. Helens in 1980). The aerosol cloud spread around the earth in two weeks and covered the planet within a year. During 1992 and 1993, the Ozone hole over Antarctica reached an unprecedented size.
The cloud over the earth reduced global temperatures. In 1992 and 1993, the average temperature in the Northern Hemisphere was reduced 0.5 to 0.6°C and the entire planet was cooled 0.4 to 0.5°C. The maximum reduction in global temperature occurred in August 1992 with a reduction of 0.73°C. The eruption is believed to have influenced such events as 1993 floods along the Mississippi river and the drought in the Sahel region of Africa. The United States experienced its third coldest and third wettest summer in 77 years during 1992.
Note how the pictures of Mt. Pinatubo look an awful lot like the eruption in Chile today. This is not a good thing to see. I was trained in childhood to look for the effects of volcanic eruptions. My grandfather saw the effects of Krakatoa in the 19th century and described to us the strange light effects this caused. When Mt. Agung in Sumatra blew its stack in 1963, we were driving from the McDonald Observatory in Texas to Kitt Peak in Tucson. Suddenly, the western sunset flared into brilliant reds and golds. My mother yelled, 'A volcano has blown up!' And my dad stopped the car and set up instruments and camera and spend the rest of the evening, studying it. They eventually wrote a book about this.
We noted that every time a volcano blew up from 1963 to 1976, it got really cold and wet, lots and lots of rain even in Tucson. One volcanic year, the rivers flooded and the desert was all green. We had to walk on boards to get to and from the buses because of the mud! We missed school because the Tanque Verde river overran the bridge, cutting off our ranch from the city.
Back to 1991: A hot June turned swiftly to freezing cold. We have a video of my son and I running around in our winter coats in the freezing cold! Danny and I began to frantically build our winter supply of wood. We were fearful. By October, we had a huge pile of wood. Only the freezing rain made it into a solid mess. We took axes to it and couldn't break it apart! It began to snow in ernest before Halloween.
'Oh my god, we are going to die!' I thought. So I strengthened the tent's roof and began to hoard food. But by November, we needed Duke, our sled dog, to haul up load after load of canned goods and bags of flour, etc. The snow got deeper and deeper. Eventually, we were in an igloo buried in the snow. We would hitch up the dog to his sled and go into the woods and fell trees since our woodpile was buried.
We survived. The howling storms were frightful. One storm, we had to brace the windows which bulged and almost blew out. When the deep snow melted, we marveled at the tree stumps left behind when we foraged for wood...they were over 4 feet tall! And Chris and I lay on the snow to cut as low as possible!
The following year was difficult, too. This time, due to the cold winter in China, the loess red dust caused huge dust storms that turned the sky over us, when the wind blew hard from the west to the east, a brilliant copper color. This dimmed the sun so we had a second very cold winter plus the snow was pink sometimes! By then, we had Sparky, our Alpine horse. He loved the very deep snow and couldn't wait to go tearing around with his sled in it. So we had a much easier time with him drawing up the mountain, all our supplies, giving Duke a break.
From my parent's book about volcanos and sunsets:
When partially blocked by trees or clouds, light from the setting sun breaks into unique beams called crepuscular rays that resemble the unusual sunsets produced by volcanic eruptions. Light from crepuscular rays scatters off gases in the atmosphere much as sunlight deflects off volcanic aerosols.
Huge volcanic eruptions cool earth, counter global warming
Pinatubo’s eruption triggered high-speed avalanches of hot ash and gas, huge mud flows that displaced about 20,000 indigenous Aeta highlanders and 200,000 people in the surrounding lowlands.Volcanic gases, according to Solidum, could also deplete the ozone, humanity’s protection from sun’s radiation.
Pinatubo eruption, for example, resulted in 15 to 25 percent ozone loss at high altitude, ozone depletion in the tropics, and highly elevated levels of acting chlorines in polar regions, Solidum said, quoting a report by the Volcanism and Climate Change American Geophysical Union.
Generally, carbon dioxide generated by volcanic eruptions enhances global warming. But the estimated 110 million tons of carbon emitted by erupting volcanoes into the atmosphere a year were much less than the 10 billion tons of carbon produced annually by human activity, Solidum said.
Not all eruptions affect the climate; only big eruptions like Pinatubo’s puncture the stratosphere, according to Solidum.
We shall see if this volcanic event is on the scale of these giant eruptions. I really don't want that, right now we have an artificial famine caused by commodity speculators, the Hubbert Oil Peak oil problems and biofuel use that diverts food from humans to cars. But if we have a global volcanic 'winter' this can turn into a catastrophe. This has happened before!
The unusual climatic aberrations of 1816 had the greatest effect on the American northeast, New England, the Canadian Maritimes, Newfoundland, and northern Europe. Typically, the late spring and summer of the northeastern U.S. are relatively stable: temperatures (average of both day and night) average about 68–77 °F (20–25 °C), and rarely fall below 41 °F (5 °C). Summer snow is an extreme rarity, though May flurries sometimes occur.
In May 1816,[4] however, frost killed off most of the crops that had been planted, and in June two large snowstorms in eastern Canada and New England resulted in many human deaths. Nearly a foot of snow was observed in Quebec City in early June, with consequent additional loss of crops—most summer growing plants have cell walls which rupture in a mild frost, let alone a snowstorm coating the soils. The result was widespread localized famines, and further deaths from those who, in a hunger-weakened state, then suffered disease as well in their less resistant condition.In July and August, lake and river ice were observed as far south as Pennsylvania. Rapid, dramatic temperature swings were common, with temperatures sometimes reverting from normal or above-normal summer temperatures as high as 95 °F (35 °C) to near-freezing within hours. Even though farmers south of New England did succeed in bringing some crops to maturity, maize and other grain prices rose dramatically. Oats, for example, rose from 12¢ a bushel the previous year to 92¢ a bushel—nearly eight times as much—and oats are a necessary staple for an economy dependent upon horses for primary transportation. Those areas suffering local crop failures then had to deal with the lack of roads in the early 19th century, preventing any easy importation of bulky food stuffs.
When we were trying to survive in our tent complex during that very cold two years, we read a lot of books about the 'Year with no summer.' Needless to say, work on the house went very, very slowly. The extreme foul weather is not good for digging and laying bricks or pouring cement! By the time the weather became cooperative, my husband was poisoned at work when the museum cut off his oxygen supply while he was working with chemicals.
So I ended up nursing my husband while living in a tent while trying to build a house. We succeeded which goes to show, determination and sweat can win out over great odds. Now, I am prepared for a possible bad winter! But this is the opposite side of global warming: we are always just one volcano away from a bout of Ice Age fun.
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