Volcanic Winter

By: Dr. Jeff Masters , 1:18 PM GMT on April 24, 2009

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"The sun was dark and its darkness lasted for eighteen months; each day it shone for about four hours; and still this light was only a feeble shadow; the fruits did not ripen and the wine tasted like sour grapes." As this Michael the Syrian quote regarding the weather of 536 A.D. demonstrates, a climate catastrophe that blots out the sun can really spoil your day. Procopius of Caesarea remarked: "During this year [536 A.D.] a most dread portent took place. For the sun gave forth its light without brightness. and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear." Many documents from 535 - 536 A.D.--the time of King Arthur in Britain--speak of the terrible "dry fog" or cloud of dust that obscured the sun, causing widespread crop failures in Europe, and summer frosts, drought, and famine in China. Tree ring studies in Europe confirm several years of very poor growth around that time, and ice cores from Greenland and Antarctica show highly elevated levels of atmospheric sulfuric acid dust existed.

Though some scientists believe the climate calamity of 535-536 A.D. was due to a comet or asteroid hitting the Earth, it is widely thought that the event was probably caused by the most massive volcanic eruption of the past 1500 years. This eruption threw so much sulfur dioxide (SO2) gas into the stratosphere that a "Volcanic Winter" resulted. Sulfur dioxide reacts with water to form sulfuric acid droplets (aerosol particles), which are highly reflective and reduce the amount of incoming sunlight. The potential eruption that led to the 535 - 536 A.D. climate calamity would have likely been a magnitude 7 event on the Volcanic Explosivity Index (VEI)--a "super colossal" eruption that one can expect to occur only once every 1000 years. The Volcanic Explosivity Index is a logarithmic scale like the Richter scale used to rate earthquakes, so a magnitude 7 eruption would eject ten times more material than the two largest eruptions of the past century--the magnitude 6 eruptions of Mt. Pinatubo in the Philippines (1991) and Novarupta in Alaska (1912).


Figure 1. An 18 km-high volcanic plume from one of a series of explosive eruptions of Mount Pinatubo beginning on 12 June 1991, viewed from Clark Air Base (about 20 km east of the volcano). Three days later, the most powerful eruption produced a plume that rose nearly 40 km, penetrating well into the stratosphere. Pinatubo's sulfur emissions cooled the Earth by about 1°F (0.5°C) for 1 - 2 years. (Photograph by David H. Harlow, USGS.)

Super-colossal eruptions
There has been only one other magnitude 7 "super-colossal" eruption in the past 1500 years--the massive eruption of the Indonesian volcano Tambora in 1815. The sulfur pumped by this eruption into the stratosphere dimmed sunlight so extensively that global temperatures fell by about 2°F (1°C) for 1 - 2 years afterward. This triggered the famed Year Without a Summer in 1816. Killing frosts and snow storms 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. The Tambora eruption was about 40% smaller than the 535 - 536 A.D. event, as measured by the number of sulfur aerosol particles deposited in Greenland ice cores.

In an article published in 2008 in the American Geophysical Union journal EOS, Dr. Ken Verosub of the University of California, Davis Department of Geology estimated that future eruptions capable of causing "Volcanic Winter" effects severe enough to depress global temperatures by 2°F (1°C) and trigger widespread crop failures for 1 - 2 years afterwards should occur about once every 200 - 300 years. Even a magnitude 6 eruption, such as the 1600 eruption of the Peruvian volcano Huaynaputina, can cause climatic change capable of killing millions of people. The Huaynaputina eruption is blamed for the Russian famine of 1601-1603, which killed over half a million people and led to the overthrow of Tsar Boris Godunov. Thankfully, the climatic impacts of all of these historic magnitude 6 and 7 eruptions have been relatively short-lived. After about two years, the sulfuric acid aerosol particles have settled out of the stratosphere, returning the climate to its former state.

Mega-colossal eruptions
Even more extreme eruptions have occurred in Earth's past--eruptions ten times more powerful than the Tambora eruption, earning a ranking of 8 out of 8 on the Volcanic Explosivity Index (VEI). These "mega-colossal" eruptions occur only about once every 10,000 years, but have much longer-lasting climatic effects and thus are a more significant threat to human civilization. According to the Toba Catastrophe Theory, a mega-colossal eruption at Toba Caldera, Sumatra, about 74,000 years ago, was 3500 times greater than the Tambora eruption. According to model simulations, an eruption this large can pump so much sulfur dioxide gas into the stratosphere that the atmosphere does not have the capacity to oxidize all the SO2 to sulfuric acid aerosol. The atmosphere oxidizes as much SO2 as it can, leaving a huge reservoir of SO2 in the stratosphere. This SO2 gradually reacts to form sulfuric acid as the OH radicals needed for this reaction are gradually produced. The result is a much longer-lasting climate effect than the 1 - 2 years that the magnitude 6 and 7 events of 535, 1600, 1815, and 1991 lasted. A magnitude 8 eruption like the Toba event can cool the globe for 6 - 10 years (Figure 3), which may be long enough to trigger an ice age--if the climate is already on the verge of tipping into an ice age. Rampino and Self (1992) argued that the sulfur aerosol veil from Toba was thick and long-lasting enough to cool the globe by 3 - 5°C (5 - 9°F), pushing the climate--which was already cooling and perhaps headed towards an ice age--into a full-scale ice age. They suggested that the response of Canada to the volcano played a particularly important role, with their model predicting a 12°C (22°F) reduction in summer temperatures in Canada. This would have favored the growth of the Laurentide ice sheet, increasing the reflectivity (albedo) of the Earth, reflecting more sunlight and reducing temperatures further. The controversial Toba Catastrophe Theory asserts that the resulting sudden climate change reduced the Earth's population of humans to 1,000 - 10,000 breeding pairs. More recent research has shed considerable doubt on the idea that the Toba eruption pushed the climate into an ice age, though. Oppenheimer (2002) found evidence supporting only a 2°F (1.1°C) cooling of the globe, for the 1000 years after the Toba eruption. Zielinski et al. (1996) argued that the Toba eruption did not trigger a major ice age--the eruption merely pushed the globe into a cool period that lasted 200 years. Interestingly, a previous super-eruption of Toba, 788,000 years ago, coincided with a transition from an ice age to a warm period.


Figure 2. The 100x30 square kilometer Toba Caldera is situated in north-central Sumatra around 200 km north of the Equator. It is comprised of four overlapping calderas aligned with the Sumatran volcanic chain. Repeated volcanic cataclysms culminated in the stupendous expulsion of the Younger Toba Tuff around 74,000 years ago. The lake area is 100 square kilometers. Samosir Island formed as a result of subsequent uplift above the evacuated magma reservoir. Such resurgent domes are typically seen as the concluding phase of a large eruption. Landsat Enhanced Thematic Mapper Plus (ETM+) browse images for path/row 128/58 (6 September 1999) and 129/58 (21 January 2001) from http://landsat7.usgs.gov/. Copyright USGS. Image source: Oppenheimer, C., 2002, "Limited global change due to the largest known Quaternary eruption, Toba 74 kyr BP?"Quaternary Science Reviews, 21, Issues 14-15, August 2002, Pages 1593-1609.


Figure 3. Total mass of sulfur dioxide and sulfate aerosol in the stratosphere (heavy solid and dotted lines, respectively) modeled for a 6 petagram stratospheric injection of SO2. Observed SO2 and aerosol mass for the 1991 Pinatubo eruption are shown for comparison. The much larger amount of SO2 in the Toba simulation soaks up all available oxidants in the stratosphere leading to a much longer lifetime of SO2 and, in turn, prolonging the manufacture of sulfate aerosol. Data from Read et al. (1993) and Bekki et al. (1996). Image source: Oppenheimer, C., 2002, "Limited global change due to the largest known Quaternary eruption, Toba 74 kyr BP?"Quaternary Science Reviews, 21, Issues 14-15, August 2002, Pages 1593-1609.

When can we expect the next mega-colossal eruption?
Given the observed frequency of one mega-colossal magnitude 8 volcanic eruption every 1.4 million years, the odds of another hitting in the next 100 years is about .014%, according to Mason et al., 2004. This works out to a 1% chance over the next 7200 years. Rampino (2002) puts the average frequency of such eruptions at once every 50,000 years--about double the frequency with which 1-km diameter comets or asteroids capable of causing a similar climatic effect hit the Earth. A likely location for the next mega-colossal eruption would be at the Yellowstone Caldera in Wyoming, which has had magnitude 7 or 8 eruptions as often as every 650,000 years. The last mega-colossal eruption there was about 640,000 years ago. But don't worry, the seismic activity under Yellowstone Lake earlier this year has died down, and the uplift of the ground over the Yellowstone caldera that was as large as 7 cm/yr (2.7 inches/yr) between 2004 - 2006 has now fallen to 4 cm/yr, according to the Yellowstone Volcano Observatory. The USGS states that "the Yellowstone volcanic system shows no signs that it is headed toward such an eruption. The probability of a large caldera-forming eruption within the next few thousand years is exceedingly low".

What would happen if a magnitude 8 mega-colossal eruption were to occur today?
If a mega-colossal eruption were to occur today, it would probably not be able to push Earth into an ice age, according to a modeling study done by Jones et al. (2005). They found that an eruption like Toba would cool the Earth by about 17°F (9.4°C) after the first year (Figure 3), and the temperature would gradually recover to 3°F (1.8°C) below normal ten years after the eruption. They found that the eruption would reduce rainfall by 50% globally for the first two years, and up to 90% over the Amazon, Southeast Asia, and central Africa. This would obviously be very bad for human civilization, with the cold and lack of sunshine causing widespread crop failures and starvation of millions of people. Furthermore, the eruption would lead to a partial loss of Earth's protective ozone layer, allowing highly damaging levels of ultraviolet light to penetrate to the surface.

Not even a mega-colossal eruption of this magnitude would stop global warming, though. The level of greenhouse gases in the atmosphere would not be affected by the volcanic eruption, and warming would resume where it left off once the stratospheric dust settled out in a decade. With civilization crippled by the disaster, greenhouse gas emissions would be substantially reduced, though (small solace!) If we really want to say goodbye to civilization, a repeat of the only magnitude 9 eruption in recorded history should do the trick--the magnitude 9.2 La Garita, Colorado blast of 27.8 million years ago (Mason et al., 2004).


Figure 4. Annual near-surface temperature anomalies for the year following a mega-colossal volcanic eruption like the Toba eruption of 74,000 years ago, if it were to occur today. Most land areas cool by 22°F (12°C) compared to average. Some areas, like Africa, cool by 29°F (16°C). Image credit: Jones, G.S., et al., 2005, "An AOGCM simulation of the climate response to a volcanic super-eruption", Climate Dynamics, 25, Numbers 7-8, pp 725-738, December, 2005.

What would happen if a magnitude 7 super-colossal eruption were to occur today?
An eruption today like the magnitude 7 events of 535 A.D. or 1815 would cause cause wide-spread crop failures for 1 - 2 years after the eruption. With food supplies in the world already stretched thin by rising population, decreased water availability, and conversion of cropland to grow biofuels, a major volcanic eruption would probably create widespread famine, threatening the lives of millions of people. Wars over scarce resources might result. However, society's vulnerability to major volcanic eruptions is less than it was, since the globe has warmed significantly in the past 200 years. The famines from the eruptions of 1600 and 1815 both occurred during the Little Ice Age, when global temperatures were about 1.4°F (0.8°C) cooler than today. Crop failures would not be as wide-spread with today's global temperatures, if a suer-colossal eruption were to occur. Fifty years from now, when global temperatures are expected to be at least 1°C warmer, a magnitude 7 eruption should only be able to cool the climate down to year 2009 levels.

Volcanoes also warm the climate
While volcanoes cool the climate on time scales of 1 - 2 years, they act to warm the climate over longer time scales, since they are an important source of natural CO2 to the atmosphere. Volcanoes add 0.1 - 0.3 gigatons (Gt) of carbon to the atmosphere each year, which is about 1 - 3% of what human carbon emissions to the atmosphere were in 2007, according to the Global Carbon Project. In fact, volcanoes are largely responsible for the natural CO2 in the atmosphere, and helped make life possible on Earth. Why, then, haven't CO2 levels continuously risen over geologic time, turning Earth into a steamy hothouse? In fact, CO2 levels have fallen considerably since the time of the dinosaurs--how can this be? Well, volcano-emitted CO2 is removed from the atmosphere by chemical weathering. This occurs when rain and snow fall on rocks containing silicates. The moisture and silicates react with CO2, pulling it out of the air. The carbon removed from the air is then washed into the sea, where it ends up in ocean sediments that gradually harden into rock. Rates of chemical weathering on Earth have accelerated since the time of the dinosaurs, largely due to the recent uplift of the Himalaya Mountains and Tibetan Plateau. These highlands undergo a tremendous amount of weathering, thanks to their lofty heights and the rains of the Asian Monsoon that they capture. Unfortunately, chemical weathering cannot help us with our current high levels of greenhouse gases, since chemical weathering takes thousands of years to remove significant amounts of CO2 from the atmosphere. It takes about 100,000 years for silicate weathering to remove 63% of the CO2 in the atmosphere. Thus, climate models predict that chemical weathering will solve our greenhouse gas problem in about 100,000 - 200,000 years.

For further information
PBS TV special on the 535-536 A.D. disaster.
Newspaper articles on the 535-536 A.D. disaster.
Volcanic winter article from wikipedia.
Realclimate.org has a nice article that goes into the volcano-climate connection in greater detail.

References
Bekki, S., J.A. Pyle, W. Zhong, R. Toumi, J.D. Haigh and D.M. Pyle, 1996, "The role of microphysical and chemical processes in prolonging the climate forcing of the Toba eruption", Geophysical Research Letters 23 (1996), pp. 2669-2672.

Jones, G.S., et al., 2005, "An AOGCM simulation of the climate response to a volcanic super-eruption", Climate Dynamics, 25, Numbers 7-8, pp 725-738, December, 2005.

Rampino, M.R., and S. Self, 1993, "Climate-volcanism feedback and the Toba eruption of 74,000 years ago", Quaternary Research 40 (1993), pp. 269-280.

Mason, B.G., D.M. Pyle, and C. Oppenheimer, 2004, "The size and frequency of the largest observed explosive eruptions on Earth", Bulletin of Volcanology" 66, Number 8, December 2004, pp 735-748.

Oppenheimer, C., 2002, "Limited global change due to the largest known Quaternary eruption, Toba 74 kyr BP?"Quaternary Science Reviews, 21, Issues 14-15, August 2002, Pages 1593-1609.

Rampino, M.R., 2002, "Supereruptions as a Threat to Civilizations on Earth-like Planets", Icarus, 156, Issue 2, April 2002, Pages 562-569.

Read, W.G., L. Froidevaux and J.W. Waters, 1993, "Microwave Limb Sounder measurements of stratospheric SO2 from the Mt. Pinatubo eruption", Geophysical Research Letters 20 (1993), pp. 1299-1302.

Verosub, K.L., and J. Lippman, 2008, "Global Impacts of the 1600 Eruption of Peru's Huaynaputina Volcano", EOS 89, 15, 8 April 2008, pp 141-142.

Zielinski, G.A. et al., 1996, "Potential Atmospheric Impact of the Toba Mega-Eruption 71,000 Years Ago", Geophysical Research Letters, 23, 8, pp. 837-840, 1996.

Portlight moves to provide relief for South Carolina wildfires
South Carolina's biggest wildfire in more than three decades --a blaze four miles wide--destroyed dozens of homes near Myrtle Beach yesterday. Portlight Strategies, Inc. is preparing to respond to this disaster, focusing on providing drinks and sanitary products to firefighters, particularly to rural volunteer fire departments and other first responders which do not have the same resources as some of the larger paid departments. To help out, visit the Portlight South Carolina fire relief web page. Thanks!

Jeff Masters

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Quoting Stormchaser2007:
And heres a view of SAL off the African coast.


Stormchaser, when is the SAL usually the strongest or when does it peak?

CaneAddict, good to see ya. You sound like me and my emergency preparedness blog :o)
Member Since: September 3, 2007 Posts: 3 Comments: 1519
82. I'm not even NEAR ready yet. I was kind of hoping to be outta here before the season hit but it looks like i'm stuck here for a bit longer...perhaps back to San Diego by early July. Guess I better stock up on a few things but for the most part, if I see anything coming, I'm getting in the car and leaving.
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Hey everyone!...The season is coming and is coming fast...All I can say is this thunderstorm activity coming off Africa better be short-lived....I don't even wan't to think of what it could result in come the heart of the season...I believe we will see our first "official" Tropical Wave real soon...anyways I was supposed to come out with my Hurricane Season Forecast on April 1st but that never happened and i have not gotten around to it...so May 1st I will release my forecast for those interested at my website...canewatch.webs.com
How is everyone? Everyone prepared?
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And heres a view of SAL off the African coast.

Member Since: June 9, 2007 Posts: 4 Comments: 15946
10-day forecast for West Palm .... No Rain :(
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Areas over Africa starting to pop up again. Theres a small chance one of these becomes an official Tropical Wave.

Member Since: June 9, 2007 Posts: 4 Comments: 15946
Afternoon everyone. Think I've corrected the temp problem. This sensor is different than the one in PC, less heat shielding. Also relocated the anemometer to the roof. Prolly like 15 ft or so in the air.


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Quoting Cotillion:
It is 37 days, 5 hours, 35 minutes and 17 seconds until Monday, June 1, 2009 at 12:00:01 AM (Praia time).

Getting closer.


Wow, almost one month. Pre/post-season went by fast!
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Going to be an active Cape Verde year.
More tropical waves rolling off the coast.
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Quoting weathermanwannabe:
Hey 456; nice to see you again.........Does AEW mean "April - Early - Waves?".......


African Easterly Waves.
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Hi everyone! Great post Dr. Masters. While I don't have to worry too much about hurricanes and tornados here, I do worry about earthquakes and my close proximity to Yellowstone.

I don't mind a little early wave watching. That means it's time to start warming up my favorite links :o) I lost all mine at the start of the season last year and had a heck of a time getting them all saved again. I've been lurking through the winter, but it sure is good to see more of the tropical fans now.

Member Since: September 3, 2007 Posts: 3 Comments: 1519
Off for the Weekend and everyone enjoy the weekend as much as you can.......I am reposting, if is will post as a link on my comment, the link to a "polar" satellite animation that someone posted on here last h-season..........Nice view of the activity in Africa 456 was referring to but you can clearly see how low it is in the latitudes as is typical this time of year.....Great shot/link for the upcoming season......Have a Great One Folks.

http://www.meteo.psu.edu/~gadomski/SAT_NHEM/atlanim8ir.html
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Am I missing something? How do I vote in the "Wunderpoll" at the top of this page? I can check a choice but I don't see how to submit the vote. Thanks for anyone's help.
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Ya it just keeps on creeping closer and closer.
Member Since: August 12, 2007 Posts: 2 Comments: 2838
It is 37 days, 5 hours, 35 minutes and 17 seconds until Monday, June 1, 2009 at 12:00:01 AM (Praia time).

Getting closer.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting Weather456:
Gustav, Ike, Paloma and Alma Retired/2009 FAQ



can we atleast wait until April is over before we start wave watching?
;-)
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Afternoon,to all,hope everyone has a great weekend,we here in the northeast are looking forward to a preview of summer,as winter slowly recedes in the rearview mirror.
"Sighs with relief"
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67. Skyepony (Mod)
I was suprised by how little volcanos contribute CO2 compared to people.

Some of the weather news today..the wire is humming..

Experts Probe Urban Growth, Climate Change Links in Africa w/Photo
. intensity of severe storms, will continue to increase in coming decades. Gasingayire says recent shifts in familiar weather patterns, caused by climate change, have made traditional agriculture across Africa less profitable, and driven Africans from ...

'Climate change' forces Eskimos to abandon village w/Photo
Story Highlights
♦Floods blamed on climate change forcing Alaskan village to move 9 miles away
♦Twenty-six other Alaskan villages are in immediate danger, officials say
♦Move comes as indigenous people hold Anchorage summit on the crisis
♦UN: Climate change will force displacement of 150 million people by 2050

Mandatory water rationing due for San Diego County
Strict water rationing rules loom for San Diego County because of lingering drought conditions.

Fire fight in my area.. Small fire contained, but larger blaze jumps fire lines near Bithlo
Firefighters contained the smaller of two brush fires near Bithlo on Monday, but the larger one repeatedly jumped fire lines, a Florida Division of Forestry official said

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Hey 456; nice to see you again.........Does AEW mean "April - Early - Waves?".......
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Quoting TampaSpin:
Look at the Hot pockets off the Coast of North America.....Wow!


That would be the gulfstream that you are seeing.
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Quoting JRRP:
61
tropical waves ??


yh
Member Since: July 24, 2005 Posts: 407 Comments: 19076
63. JRRP
61
tropical waves ??
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Local news stations are reporting that firefighters had the Horry County fire 50% controlled as of this morning. Low winds last night helped their efforts. However, now that it's mid-day, we have quite a stiff sea-breeze blowing and humidity levels have dropped as the temperature has risen.
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Gustav, Ike, Paloma and Alma Retired/2009 FAQ

Member Since: July 24, 2005 Posts: 407 Comments: 19076
Thanks for this very interesting post, Dr. Masters.

I will not ever be hunting volcanic eruptions. The video of the pyroclastic flow from Pinatubo still freaks me out when I see it.
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52, they are showing up in Pa. also.

Link
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Thanks Dr. M; very imformative topic (guess I am safe to take the Family to Yellowstone this Summer)and appreciate all the research you did to put this particular Blog together....
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Good informative post, Dr.Masters!

I think the 1783 Laki eruption is worth a mention too and might be more comparable to the 536AD event, if indeed it was a volcanic eruption.

The dry fog described in the 536AD eruption sounds very similar to the dry fog event of 1783/84 described by Franklin.


During several of the summer months of the year 1783, when the effect of the sun's rays to heat the earth in these northern regions should have been greater, there existed a constant fog over all Europe, and a great part of North America. This fog was of a permanent nature; it was dry, and the rays of the sun seemed to have little effect towards dissipating it, as they easily do a moist fog, arising from water. They were indeed rendered so faint in passing through it, that when collected in the focus of a burning glass they would scarce kindle brown paper. Of course, their summer effect in heating the Earth was exceedingly diminished. Hence the surface was early frozen. Hence the first snows remained on it unmelted, and received continual additions. Hence the air was more chilled, and the winds more severely cold. Hence perhaps the winter of 1783-4 was more severe than any that had happened for many years.



It could be that the 536AD eruption wasn't explosive but perhaps a fissure eruption in which most of the SO2 emissions were released into the troposphere as opposed to the stratosphere as they would in explosive events.
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http://www.naplesnews.com/news/2009/apr/22/firefighters-keeping-eye-1000-acre-wildfire-big-cy/

Smokey here but not nearly like early this morning. This morning, I had to look hard to see the house directly across the street. This fire is about 15 miles East of here. The Interstate is probably closed for the weekend. The Eastern edge of the fire is Highway 29, which is the NS road that runs North from Everglades City.
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Gotta run BBL tonite. Prayers are needed for everyone in those fires. Thank Portlight for responding to their needs! Great JoB!
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Speaking of less 'arcane' volcanoes though, Vesuvius - one of the 'Decade' volcanoes - hasn't gone off for a long while. Not since 1944.

Longest lull in a long time. 500 years, Wiki says.

Considering its violent history, that doesn't particularly bode well.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Doc links to a 2005 statement above with reference to "no signs."

Don't get me wrong, they still don't think so.

This is from Nov 2007 (before the swarm at the end of 2008, beginning 2009). I'd like to see that "current period of uplift will cease, to be followed by another cycle of subsidence" actually happen.

"Interestingly, the Yellowstone caldera has remained seismically quiet during the past three years of uplift. An earlier article on our website, Satellite Technologies Detect Uplift in the Yellowstone Caldera provides context on the techniques used to study these movements. The new activity, though more rapid than those previously measured at Yellowstone, is not unprecedented at large calderas around the globe. Given the absence of large earthquakes, earthquake swarms and anomalous behavior of Yellowstone's hydrothermal system (its geysers, mud pots and fumaroles), we find little indication that the volcano is moving towards an eruption. At this time, volcanic eruptions and hydrothermal explosions remain an unlikely possibility. Given the geologic history of the area, it is likely that the current period of uplift will cease, to be followed by another cycle of subsidence. When this might happen, though, is unknown."

Link

Still don't like the uplift trend at yellowstone.

From 2007:



Most recent data (ignore the 1996 in the header):


Plot Last Updated: Friday, April 24, 2009 09:25:58 MDT
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3.4 M - OHIO

* 8 km (5 miles) NNW from Oak Hill, OH
* 10 km (6 miles) SSE from Jackson, OH
* 17 km (10 miles) S from Coalton, OH
* 119 km (74 miles) SSE from Columbus, OH
* 278 km (173 miles) SW from Pittsburgh, PA
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I will release my Atlantic basin Forecast for the upcoming season on May 1st. I have already done some preliminary work under the tab TROPICAL PREDICTION ANALYSIS at my Website and have spoke about it in a Forum if anyone would like to input their thoughts.

http://tampaspinsweather.webs.com/apps/forums/topics/show/659989-tropical-outlook-
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Quoting Patrap:
Erik Larson's book is a good read.



I got that book for a Christmas Present and read it in January. I loved it!
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Hi Dr Masters and all who come here!

Happy Friday to you all.

Enjoyed your header info on the Volcano reactions over the years.

Have a good weekend and all those waves coming off Africa have my permission to continue to be sheared to death...for the next year or so! LOL

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The ICW is very narrow through that area....if the fire jumps the ditch it's gonna be really bad news for Myrtle....
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Great blog, thanks Doc.

Though, when one of the World's calderas does go off - of which there are more than one - we'll certain know about it. With earthquakes, certain building codes and technology can help in keeping buildings upright. With tropical cyclones, you can improve flood defences and again, make buildings much more sure against high winds.

Against pyroclastic flows, huge explosions and ash choking out the sky, what can you do?

Still, fascinating subject.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting MrMarcus:
Great article. Just wish it didn't have the political spin toward the end...


Guess you are referring to this!...LOL

Unfortunately, chemical weathering cannot help us with our current high levels of greenhouse gases, since chemical weathering takes thousands of years to remove significant amounts of CO2 from the atmosphere. It takes about 100,000 years for silicate weathering to remove 63% of the CO2 in the atmosphere. Thus, climate models predict that chemical weathering will solve our greenhouse gas problem in about 100,000 - 200,000 years.
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Great article. Just wish it didn't have the political spin toward the end...
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42. Seastep 11:42 AM EDT on April 24, 2009
Yellowstone was mumbling yesterday. Hope Doc didn't jinx us. :)

Calm today, though.

For comparison, a more "normal" day first followed by yesterday:


Ouch, don't say that!

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Great topic Doc.
What effect did the 1883 eruption of Krakatoa have on world temps. I remember a doco on it and they had red sky's in Britain and Europe for a few months after. The eruption was the loudest natural noise ever heard on earth. The cataclysmic explosion was distinctly heard as far away as Perth in Western Australia, about 1,930 miles (3,110 km) away, and the island of Rodrigues near Mauritius, about 3,000 miles (5,000 km) away. The pressure wave from the final explosion was recorded on barographs around the world, which continued to register it up to 5 days after the explosion. The recordings show that the shockwave from the final explosion reverberated around the globe 7 times in total. Ash was propelled to a height of 80 km (50 mi).

Cheers AussieStorm
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Yellowstone was mumbling yesterday. Hope Doc didn't jinx us. :)

Calm today, though.

For comparison, a more "normal" day first followed by yesterday:



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Taz you have mail!
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38. Tazmanian 11:14 AM EDT on April 24, 2009
all my GOD you all better take a look at this

Depth 26.C Isotherm



I believe that is slightly below normal tho!
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man the Caribbean is this cooking
Member Since: May 21, 2006 Posts: 5091 Comments: 115362
all my GOD you all better take a look at this

Depth 26.C Isotherm

Member Since: May 21, 2006 Posts: 5091 Comments: 115362
TS:cool sat pic!!!!,charleston:thanks for the WF update,I just saw that on my local news about our WF here near allagator alley,They might have to shut 75 down again if theres to much smoke....
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Depth 26.C Isotherm

Member Since: May 21, 2006 Posts: 5091 Comments: 115362
ssts are pretty cold off the coast of Africa,kills anything that comes off the coast,now if they could make it west a little the water temps rise
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They have been like that for the last week or so... as soon as they hit the water and shear... poof gone
Member Since: October 1, 2007 Posts: 81 Comments: 26511

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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