What would be the effects of a catastrophic volcanic eruption on global warming?

[MoonRiver]

I'm thinking of something along the lines of Krakatoa.

Would such an eruption counteract some of the warming effects, or make the situation much worse?

I'm watching a program about volcanoes on the History Channel and this question came to mind.

[Vexatious Ape]

1. Good question.

Krakatoa made for a real cold winter everywhere.

[MoonRiver]

2. Yes, that's what made me wonder.

Calling all DU volcanologists! :)

[DRoseDARs]

4. The effects would only be temporary; it wouldn't magically remove what's already in the atmosphere..

...only add to it. The dust from such a large explosion would reduce the global average temperature for a short while, but also additional tons upon tons of greenhouse gases would be added, compounding our problem.

[Buzz Clik]

9. great post.

[sam sarrha]

14. i am afraid the CO2 and Sulpheric acid from a big eruption would have very long effects

[DRoseDARs]

27. You misread my meaning, I apologize for not being clear. I was refering to the cooling effects. n/t

[sam sarrha]

30. i was refering to the cooling effects.. superVolcano WINTER..

[CoffeeCat]

3. A Krakatoa would be bad, but not as bad...

...as the Bushatoa eruptions that began in 2000 and have left our country devastated.

Then, there's Mount St. Cheney---one cannot underestimate the destruction of the
magma that is his foreign-policy.

[seasat]

5. Massive eruptions pump out a ton of reflective particles

The result would be cooling. The sulfur dioxides from a massive eruption will temporarily increase reflectance of sunlight from the earth. Massive volcanic eruptions also inject a huge amount of chlorine into the upper atmosphere. This results in a temporary lowering of ozone. Unlike CFCs, chlorine has a very short residence time and rains out quickly so like the cooling, the effect is temporary. The greenhouse gases released by volcanoes are pretty small. The total annual emissions by all volcanoes are estimated to be 1/150th of the emissions due to human activities.

[MoonRiver]

10. Do you know how long earth's temperatures were effected by Krakatoa?

Of course we weren't on the verge of a global warming catastrophe, so the data probably wouldn't be highly relevant today.

[seasat]

19. Here is an excellent BLOG at real climate.org on volcanoes.

I'm not an expert on volcanoes. The bloggers here are climate scientists and they link to a number of studies on the subject. One of the replies to the blog quoted a Wiki article stating that Krakatoa may have lowered the temperature by 1.2° and affected climate for 5 years (LINK).

[sam sarrha]

16. St helen's was a 1 Cubic KM eruption.. Toba was a 2800 Cubic Km eruption 75k yrs ago, super volcanos

can ruin your whole day..and Toba is getting active again

[jpak]

6. Cooling

The eruption of Tambora (Indonesia) in 1815 resulted in the "Year without Summer"...

http://en.wikipedia.org/wiki/Year_Without_a_Summer

The eruption of Mt. Pinatubo reduced global temps by 0.6 degrees C...

http://earthbulletin.amnh.org/D/3/1/index.html

[kestrel91316]

7. It would temporarily MASK the symptoms. Sort of like an injection

of Depomedrol (long-acting corticosteroid)in a cat with flea allergy dermatitis..........WITHOUT bothering to control the actual fleas.

Not helpful for more than a little while.

[don954]

20. something tells me your a vet... ;)

[kestrel91316]

25. Yeah. But some folks get nasty if I dare to actually say it

more often than once a year.

The nerve of me to speak as an authority on matters of animal health and related topics............

We have at least one other vet here who got tired of attacks by DUs resident vet-haters and quit posting for the most part. I know 'cause she told me privately. Lovely, huh?

[MoonRiver]

26. I don't understand why on earth anybody on DU would hate vets!

Our vet is practically family.

I personally invite you to reveal all you know about animal care. My beloved dog is so important to me. I want to know everything I can to keep her healthy and safe.

[kineneb]

29. vets good, big volcanos bad

know anything about chickens? I have a wonderful pet chicken, which makes my local vet (also a personal friend) chuckle and tell me she doesn't treat birds. Fortunately, Henrietta seems very healthy. And, yes, she is also a member of our flock...er, I mean family.
....

and on volcanos- they can send up tremendous quantities of ash and gas, which could cause temporary "cooling". The effect would only last several years until the particulates settled out of the atmosphere, and all would return to a regular pattern. So long term, say 10 years, almost no effect.

I grew up spending lots of time around Mt. Lassen, and now live in another volcanic area, Lake Co. CA. One runs across sulfur fume holes every once in a while. Pewww. Volcanos, ya' just get used to them after while...

[whistle]

8. There was an article in Scientic America a few months ago about this

<snip>
January 05, 2007
Scientific Nature: Researchers Use Volcanic Eruption as Climate Lab When Mount Pinatubo erupted in 1991 it left a trail of evidence in the skies that is helping scientists decipher the workings of the global climate

By David Biello

ASHES TO CLIMATE: The eruption of Mount Pinatubo in 1991 provides a natural experiment for scientists to understand the complex workings of Earth's climate. Earth's climate cannot be replicated in a lab. So to understand how this critical component of the planet's heat regulation works, scientists must rely on "natural experiments." Such natural experiments take apocalyptic form, such as the eruption of Mount Pinatubo in the Philippines in June 1991 that sent 10 cubic kilometers of ash, gas and other materials sky high. By tracking how this eruption affected the global climate--and determining how to trace its footprint in other records--scientists have turned the catastrophe into a tool for comprehension. "The big problem with climate--and trying to study it--is you can't play with it in the lab," says atmospheric scientist Joanna Futyan of Columbia University. "We were trying to use this abrupt event as a natural experiment: something dramatic happened and you can look at how the atmosphere responds to it."

Futyan and physicist John Harries of Imperial College London analyzed how the atmosphere's humidity and temperature responded to the eruption as well as the overall radiative balance of the planet--in other words, the difference between the energy in sunlight absorbed by Earth versus the amount radiated back to space. The spectrum of this energy sent back into space from the surface (measured via satellite) has changed in the past 30 years as part of global warming, but the rate and magnitude of this change remain difficult to measure and rely on a variety of atmospheric processes, such as the amount of water vapor.

The atmospheric response to the Pinatubo eruption reveals that this system reacts rapidly, with sunlight-blocking sulfate aerosols ejected by the volcano cooling the planet within four months. By six months, the planet radiated 2.6 watts per square meter less heat to space than before the eruption. Humidity dropped as a result, but slowly, and by the end of 1992 the climate had once again reached equilibrium, the researchers write in the January 2 Geophysical Research Letters. "From the observations of Pinatubo, the net flux brings itself back into balance quickly," Futyan says.

Pinatubo also left its mark on the weather. When the volcano erupted, it sent sulfur dioxide shooting into the atmosphere, where a wavelength of ultraviolet light transformed some of the sulfur molecules into a lighter isotope--a unique chemical sign of such stratospheric eruptions. Falling back to the surface, the sulfate bearing this specific isotopic ratio collected in undisturbed areas, such as the snow pack on Antarctica. Isotope chemist Mark Thiemens of the University of California, San Diego, and his team dug through 30 tons of snow in search of such an isotopic record, which has already been observed in the geologic strata of ancient Earth.

Both Pinatubo and its predecessor--the eruption of Mount Agung in 1963--left such traces in the snow, while lesser eruptions that did not blow as sky high left different marks, Thiemens and his team reveal in the January 5 Science. By understanding this chemistry, it may be possible to extend the volcanic record--and its influence on climate--back in time.

The effects of catastrophic eruptions like Pinatubo may be transitory, but their record both in the climate and its residue present a picture of how the climate may respond to other so-called forcings, such as human emissions of greenhouse gases. It also helps assess how this complex system might react to human attempts to tinker with it in order to avoid the potentially catastrophic effects of such climate change--such as injecting sulfate aerosols into the sky as proposed by atmospheric chemist and Nobel laureate Paul Crutzen. "It is a quantitative way to see how sensitive the stratosphere is to perturbations," Thiemens notes. "It gives you a feel for the chemistry because nature has run some of the experiments for you."
<more>
http://www.sciam.com/article.cfm?articleID=F4890BEE-E7F2-99DF-3978F15888CDF19C

[MoonRiver]

Great article!

Thanks!

[whistle]

22. Glad I could provide something useful....

....no clear cut answers out there, we just need clear thinkers, hard work and sacrifice

[Jonathan50]

11. Mt Tambora in Indonesia in 1815 was the largest eruption since AD 181

Tambora was considerably more violent than was Krakatoa.

http://en.wikipedia.org/wiki/Mount_Tambora

<blockquote>The eruption created global climate anomalies; 1816 became known as the Year Without a Summer because of the impact on North American and European weather. In the Northern Hemisphere, agricultural crops failed and livestock died, resulting in the worst famine of the 19th century.</blockquote>

[sam sarrha]

12. Google: Toba ..Mt St Helen's was 1 cubic Kilometer, Toba was a 2800cubic Kilometer eruption

75,000 years ago. it is a Super Volcano.. Google: super volcano, yellowstone is in a caldera of a super volcano that erupted , 2400 cubic Km-and 25 cubic KM, and sent a significant amount of ash as far as Mexico city

Mt Toba is ~350 miles from the earthquake that caused the Tsunami's in Indonesia recently.. and is becoming more active

when the subduction earthquake, the 'Big One', expected near Seattle expected to be an 8.5R to a 9.something and last up to 15 to 20 minutes all the volcano's from alaska thru Washington to Calif ..Baker, Hood, Adams, St Helen's, Rainer, Shasta, Larson and Mammoth are expected to erupt.. it is said that when the 'Big One' hits Seattle there wont be a building left standing in Portland oregon, the expect to have shock waves coming straight up our of the ground en Excess of 2.5 G's. their earthquakes are not side to side.. but up and down.

there is a beach a few miles north of Seattle where the land rose 27 feet out of the Sound, you can see the limpet marks from the old tidal zone on the cliff edges

[MoonRiver]

15. Nature is and has always been humans' nemesis.

As in "the best laid plans"...

[don954]

21. look on the bright side!

with that much fresh magma exposed, there will be enough geothermic power to power the remaining united states... :evilfrown:

[sam sarrha]

23. super volcano's do not produce magma..flufy Mt St Helen's ash only and blow it into the stratospher...

it takes a long time for it to settle out and the sulphuric acid makes smog that can last for centuries, it is estimated that when Toba went off 75K years ago it reduced the population of humans to about 1000... after the ice age ended about 36 individuals entered what is now Eruope and the rest is history

[flyingfysh]

13. it temporarily slows down global warming

This happened with Pinatubo in the Phillipines. The sulfur dioxide thrown up into the atmosphere lessened the effects of global warming for the next 3 years.

[MoonRiver]

17. YELLOWSTONE!

Site of a future super volcano "caldero" (sp?). Now talking about this on History Channel. :scared:

[shadowknows69]

18. I've heard saidd if Yellowstone goes up

we are well and truly fucked.

[Warpy]

24. Krakatoa wasn't a supervolcano

along the lines of Yellowstone or the Valle Grande in NM. Krakatoa produced one "year without a summer." Mt. Tambora had done the same eighty or so earlier. The effect was brief, in other words, and there was no lasting change to worldwide climate.

A supervolcano would devastate whatever country it happened to be in--and the US has at least four classified as dormant, not extinct. Either of the two cited above would likely wipe out everything in the western half of the country, probably up to the Appalachians, by smothering it in ash. There are layers of tuff (soft sedimentary rock from ash) that are twenty to thirty feet thick here in NM. Consider that it might be two or three times that depth in the weeks following the eruption. There would be a massive die off of species world wide because the climate would be affected for a decade or more.

A supervolcano would probably end much of the warming, but the cost would be horrific.

No thanks.

[Clarkie1]

28. In James Lovelock's view (author of the "Gaia hypothesis")

There is a chance we may be saved by an unexpected event such as a series of volcanic eruptions severe enough to block out sunlight and so cool the Earth. But only losers would bet their lives on such poor odds. Whatever doubts there are about future climates, there are no doubts that greenhouse gases and temperatures both are rising.

We have stayed in ignorance for many reasons; important among them is the denial of climate change in the US where governments have failed to give their climate scientists the support they needed. The Green lobbies, which should have given priority to global warming, seem more concerned about threats to people than with threats to the Earth, not noticing that we are part of the Earth and wholly dependent upon its well being. It may take a disaster worse than last summer's European deaths to wake us up.

Opposition to nuclear energy is based on irrational fear fed by Hollywood-style fiction, the Green lobbies and the media. These fears are unjustified, and nuclear energy from its start in 1952 has proved to be the safest of all energy sources. We must stop fretting over the minute statistical risks of cancer from chemicals or radiation. Nearly one third of us will die of cancer anyway, mainly because we breathe air laden with that all pervasive carcinogen, oxygen. If we fail to concentrate our minds on the real danger, which is global warming, we may die even sooner, as did more than 20,000 unfortunates from overheating in Europe last summer.

I find it sad and ironic that the UK, which leads the world in the quality of its Earth and climate scientists, rejects their warnings and advice, and prefers to listen to the Greens. But I am a Green and I entreat my friends in the movement to drop their wrongheaded objection to nuclear energy.

Even if they were right about its dangers, and they are not, its worldwide use as our main source of energy would pose an insignificant threat compared with the dangers of intolerable and lethal heat waves and sea levels rising to drown every coastal city of the world. We have no time to experiment with visionary energy sources; civilisation is in imminent danger and has to use nuclear - the one safe, available, energy source - now or suffer the pain soon to be inflicted by our outraged planet.

James Lovelock, author of the "Gaia Hypothesis"
http://www.ecolo.org/media/articles/articles.in.english/love-indep-24-05-04.htm