Chile's volcano not likely to affect the climate
It's been a busy month for natural disasters, and I haven't found time to talk about Chile's Chaiten volcano, 760 miles (1,220 km) south of the capital Santiago. The volcano started erupting on May 2 for the first time in thousands of years, spewing ash, gas and molten rock into the air, forcing the evacuation of thousands of people. Did this mighty eruption have a cooling effect on the climate?
Figure 1. This May 5, 2008 image from NASA's Terra satellite caught Chaiten erupting. Image credit: NASA.
Many historic volcanic eruptions have had a major cooling impact on Earth's climate. However, Chaiten is very unlikely to be one of them. To see why this is, let's examine recent volcanic eruptions that have had a significant cooling effect on the climate. In the past 200 years, Mt. Pinatubo in the Phillipines (June 1991), El Chichon (Mexico, 1982), Mt. Agung (Indonesia, 1963), Santa Maria (Guatemala, 1902) Krakatoa (Indonesia, 1883), and Tambora (1815) all created noticeable cooling. As one can see from a plot of the solar radiation reaching Mauna Loa in Hawaii (Figure 2), the Mt. Pinatubo and El Chichon eruptions caused a greater than 10% drop in sunlight reaching the surface. The eruption of Tambora in 1815 had an even greater impact, triggering the famed Year Without a Summer in 1816. Killing frosts and snowstorms in May and June 1816 in Eastern Canada and New England caused widespread crop failures, and lake and river ice were observed as far south as Pennsylvania in July and August. Volcanic eruptions cause this kind of climate cooling by throwing large amounts of sulfur dioxide gas into the stratosphere. This gas reacts with water to form sulphuric acid droplets (aerosol particles), which are highly reflective, and reduce the amount of incoming sunlight.
You'll notice from the list of eruptions above that all of these climate-cooling events were from volcanoes in the tropics. Above the tropics, the stratosphere's circulation features rising air, which pulls the sulfur-containing volcanic aerosols high into the stratosphere, where the upper-level winds circulate them all around the globe. These aerosol particles take a year or two to settle back down to earth, since there is no rain in the stratosphere to help remove them. However, if a major volcanic eruption occurs in the mid-latitudes or polar regions, the circulation of the stratosphere in those regions generally features downward subsiding air, and the volcanic aerosol particles are not able to penetrate high in the stratosphere and get carried all around the globe. Chaiten is located near 40° south latitude, far from the tropics, and thus is unlikely to be able to inject significant amounts of sulfur aerosols into the stratosphere. Furthermore, the character of Chaiten's eruptions so far has been to eject a lot of silica and not much sulfur into the air. The total amount of sulfur ejected has been only about 1/10000 of what Mt. Pinatubo put into the air, according to NASA.
Figure 2. Reduced solar radiation due to volcanic aerosols as measured at Mauna Loa Observatory, Hawaii. Image credit: NOAA/ESRL.
Realclimate.org has a nice article that goes into the volcano-climate connection in greater detail. One interesting quote from the article: There can be some exceptions to the tropics-only rule, and at least one high latitude volcano appears to have had significant climate effects; Laki (Iceland, 1783-1784). The crucial factor was that the eruption was almost continuous for over 8 months which lead to significantly elevated sulphate concentrations for that whole time over much of the Atlantic and European regions, even though stratospheric concentrations were likely not particularly exceptional.
My next blog will talk about new research regarding the hurricanes/global warming connection.
Jeff Masters
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1132 - That was uncalled for. Bye!
Action: | Ignore User
Back to the weather please.
I've lived in the FL Panhandle long enough that every June 1st I fill up every gas can I have. When the season ends I have spare gas for the boat, car, truck, or lawn mower! We've alreayd started buying more canned goods than normal just as a start to preparations for this season. I've been through Ivan, Opal, Erin, and Dennis living here and that has taught me a lot about how to survive when the going gets tough after hurricanes.
Welcome back to Wally World StormW.
Hate to see anyone suffer medically.
Early action now prevents haste and worry down the Line.
Tunnels sound great,just don't ask Massachusetts engineers to build them!!!
Anything going on with Panama blob or Afrincan blob!
: )
7th inning stretch to come....................
I know that I'm not Storm (far from his level actually), but I would like to respond to your question.
There is only one fact that we can take from the GFS model (since it has become so sketchy that it can't even pick a track and can't settle on a certain intensity). And that fact is that it shows that conditions will become quite favorable for tropical development to occur there. I'm not quite sold yet that there will be a tropical system in the Northwest Caribbean by late next week into next weekend, but it does have climatology to back it up. We will have to continue watching the model to see if it can gain any consistency on track and intensity and we will have to wait until at least Friday to see if we can get some concensus from the other models before we really should start giving great consideration.
http://moe.met.fsu.edu/tcgengifs/
Weather? Anyone?
Gas price, oil, bush.... blah blah blah
When I heard that he was hospitalized my first thought was liver failure...go figure! wow.
GSM...now the spiderpig song is in my head...it sticks all day long.(so thanks for that)..but now it has the voice of Mayor Quinby because I'm thinking of Sen. Kennedy...
May I power down Sir?
Bush's policy is flawed... When you cut taxes, you aren't supposed to increase spending. Bush has been the biggest spending President in history. Unfortunately, my generation and every generation for years to come will have to pay for it.
....another one that needs to study gov't, history. Deficit spending has gone on for a very long time! I'm certainly not taking up for Bush, but get the facts right!
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Krazy I know, I'm just amazed at how long this country can see gas prices climb and nothing I mean nothing is being done by Bush to change it.
Don't worry: prices will "magically" drop around the the November election (after brokering a deal with Congress and the Oil Companies) , or, they will release some of our strategic oil reserves around the same time to ease the crunch............
Thanks...
Weather? Anyone?
Gas price, oil, bush.... blah blah blah
Ok...here's how gas prices affect the weather....if the gas prices keep going up, middle and lower class Americans will be thwarted upside-down in their personal budgets and these are ripe conditions for a major sh*@ storm. Gonna need an umbrella...
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