Saturday, October 13, 2018

When the Volcano Blows

“I don’t know where I’m-a gonna go, when the volcano blows.” -Jimmy Buffet

You may have heard about the newest eruption of a volcano in Hawaii last week. Actually, that volcano, Kilauea, has been slowly oozing lava for the last 30 years, but lately, the crater has been throwing out fountains of lava, ash, and poisonous gases.

On any given day, almost two dozen volcanoes are actively erupting, but most don’t make the news.  Many of these are located along the Pacific “Ring of Fire,” which stretches from the tip of South America up through Alaska and down the eastern coast of the Pacific to New Zealand. These volcanoes are the result of ocean crust being recycled into the mantle where it melts into magma that rises to the surface.

Other volcanoes, like Hawaii, are the result of columns of magma which rise from deep in the Earth’s mantle, which erupt through the thin ocean crust, creating new islands.

But these are only the ones on land. There is a continuous chain of volcanoes, 40,000 miles long, that snakes through the deepest parts of all the oceans of the Earth, which creates new crust and pushes the continents around the planet at a rate equivalent to the speed of your fingernail growth.

Volcanic eruptions can have a profound affect o the Earth’s climate. In fact, at least 4 of the 5 mass extinctions of life during the last 550 million years can be traced to volcanism, but not like anything ever witnessed by humans. These eruptions lasted hundreds of thousands to a million years, covering millions of square miles in a thick layer of basalt, and discharging enough sulfur and carbon dioxide to really mess with climate. One such eruption, in Siberia about 250 million years ago, coincided with “The Great Dying”, when 95% of all life on Earth went extinct.

Much smaller eruptions can have a shorter, but noticeable effect on climate. In 1991, Mt. Pinatubo in the Philippines erupted explosively, sending 20 million tons of sulfur dioxide into the high atmosphere where it created a haze of sulfuric acid. This haze reflected sunlight and dropped global average temperatures by almost 1 degree F over the next two years.

Temperatures bounced back quickly as the haze dissipated and have continued their inexorable rise today’s record levels.

When one examines the temperature records since the late 1800's, the increase in global temperatures has not been consistent with the increase in atmospheric CO2. In fact, temperatures decreased significantly from the 1950's to the 1970's.

This decline coincides with overall post-war increases in industrial production and coal-fired power generation. A byproduct of burning coal was the release of sulfur dioxide into the atmosphere, which, no surprise, resulted in a lot of sulfuric acid haze in the stratosphere.

Then in 1970, President Nixon signed the Clean Air Act.

Before the Clean Air Act (and similar legislation in Europe) sulfur emissions from power plants and vehicles caused significant air pollution, leading to acid rain, which caused widespread damage to the environment too numerous to list here. One of the requirements of the act was to decrease power plant and vehicle sulfur dioxide emissions.

Once sulfur emissions started to decline, acid rain decreased sharply throughout the industrialized world.  In addition, temperatures again started to increase and did so quite rapidly, a purely unintended consequence of the act.

So what is the lesson here? If you don’t think humans can change the climate, you’d be wrong. The history of human sulfur dioxide emissions proves it.

One of the proposed “solutions” to global warming is injecting sulfur dioxide into the stratosphere. This proposal is being taken seriously, especially by conservative think tanks who call themselves climate change skeptics. Oh the irony.

History shows that we would have to continuously inject sulfur at high altitudes to cool the Earth and we would have to burn fuel to do so, adding CO2 to the air as well. The moment we stopped, temperatures would soar. Then there is acid rain and its devastating ecological impacts including ozone depletion. The uneven application of this “solution” could cause massive droughts in areas that depend on annual monsoons. Who would manage this process is another question fraught with geopolitical peril.

Seems to me that the better course is to decrease CO2 emissions, not add a different kind of pollution to the atmosphere. Decreasing emissions is something we already know how to do.

What is lacking is the political will to do so. That, we can change . . . at the ballot box.

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