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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1784. Patrap


Swine flu precautions taken

By Kristen Hackney-redman | AVALANCHE-JOURNAL

Tuesday, April 28, 2009
Story last updated at 4/28/2009 - 1:42 am

Area and state health officials are working to prepare for the possibility of an outbreak of swine flu in Lubbock and the South Plains.

Sandy Fortenberry, public health preparedness coordinator for the city of Lubbock Health Department, said the agency is working with the Texas Department of State Health Services through conference calls to keep up-to-date on the latest information regarding swine flu. The department is also working with area health care providers to keep them up-to-date and to answer their questions about swine flu, she said.

"Since 2003, we have been developing pandemic influenza plans and we have been training and exercising on mass prophylaxis, so I think, as a city, we are very well prepared for a public health threat such as this one," Fortenberry said.
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1783. hahaguy
Morning.
Member Since: August 12, 2007 Posts: 2 Comments: 2838
'morning Cane :o)
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Good morning all :P!
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PAGASA.
At 2:00 p.m. today, a Low Pressure Area (LPA) was estimated based on satellite and surface data at 90 kms East of Casiguran, Aurora (16.2N, 124.2E). Meanwhile, a Shallow Low Pressure Area (SLPA) was estimated at 70 kms West of Dagupan City or 80 kms Northwest of Iba, Zambales (16.0N, 118.6E) and another Low Pressure Area (LPA) was estimated at 940 kms East of Northern Mindanao (10.0N, 135.0E).
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our high here today in sarasota is ONLY 87!!!!!,the thing is you'll be cooling off in the next few days,we have to wait until next october!!!!!......how many days until TC season,again????,38......37....36..........lol
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NEwx:getting kinda hott kinda early up there this year???,lol,I grew up in Ledyard,CT I don't remember it getting that hot back then,I lived their for 14yrs.....94 for a high in boston metro!!!!
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1777. NEwxguy
GM all,summer time here in the northeast again today
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Good morning everyone!

Press good to see you this year! I'll be sending you an email within the next couple of weeks to see if my son might be able to do his Eagle Scout project in conjunction with Portlight. Just wanted to give you a heads up.
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hmmmm where is dr m with his new blog???
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Quoting Weather456:
6Z GFS and one thing if notice is that it always develops the area on 4 May. Models with inconsistency tend to develop a tropical cyclone at a different time for each model run. With the GFS for each successive run, it develops the area on 4 May. Only if this consistency continues throughout the week we can be become alarm, otherwise, nothing really. I want to believe this is EPAC development tho.

06Z Apr 28
00Z April 28
18Z Apr 27
12Z Apr 27
06Z Apr 27


as I stated 4 days ago...cinco de mayo is when we should begin to have something to watch in ernest in the SW carib or western gom.....(tropically)....
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1770. vortfix 10:15 AM EDT on April 28, 2009

It looks like more rain coming.......Training

The Corpus Cristi area has the highest CAPE values at 2423! North of there and northward along the Coast will be a greatest risk currently. Later today the NW corner of Texas will be under the Gun and spread Eastward. Some of this could again be very strong storms.
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and, as a side note which justifies our mission of serving the unserved, under served and forgotten people...a ton of informationn is available to us regarding the impact at Barefoot...virtually none is available regarding the less well heeled victims...so SJ will be doing some needs assessment...
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Attention all hands!!!!!!

The video camera is up and running at the Portlight blog....SJ is making his way to the Grand Strand fire zone...

please note that our efforts are focused on the rural volunteer firefighters who don't have federal, state, and local financial resources...as well as locals outside of the Barefoot resort area...including a community of 13 mobile homes which were destroyed....
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Until i see at least 2 out 4 of the major models show something. I would not be concerned. Only the GFS is showing something.
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Roads were dry this morning but the ditches were brim full on the far SW side of Houston (FT. Bend area). From drought to bounty a bit too fast.
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Morning all!
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We're good this morning on the SE side of Houston. Until more rain hits this evening..... But it does seem awfully empty here at work. Maybe I missed the memo?
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morning
wide spread street flooding is now taking place in metro houston and surrounding areas. around 8-10 inches of rain have fallen in the area. schools have been closed and commute is very harzardous
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Quoting keyzdazeez:
what is that little mess there on the east side of mexico in that 6z gfs looks like something going on there to


Yeah I notice it too but I wouldnt jump on it too soon. The GFS aslo develop an area east of islands on a recent run but dropped it soon thereafter. Not as persistent as the one in the SW Carib
Member Since: July 24, 2005 Posts: 407 Comments: 19076
what is that little mess there on the east side of mexico in that 6z gfs looks like something going on there to
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1761. IKE
GFS has been too consistent to write it off. I follow that model quite a bit in the winter time.

My opinion...it's definitely worth following.
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1760. IKE
6Z GFS at 216 hrs.....

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Quoting Weather456:
6Z GFS and one thing if notice is that it always develops the area on 4 May. Models with inconsistency tends to develop a tropical cyclone at a different time for each model run. With the GFS for each successive run, it develops the area on 4 May. Only if this consistency continues throughout the week we can be become alarm, otherwise, nothing really.

06Z Apr 28
00Z April 28
18Z Apr 27
12Z Apr 27
06Z Apr 27


Almost to the point of annoyance.
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6Z GFS and one thing if notice is that it always develops the area on 4 May. Models with inconsistency tend to develop a tropical cyclone at a different time for each model run. With the GFS for each successive run, it develops the area on 4 May. Only if this consistency continues throughout the week we can be become alarm, otherwise, nothing really. I want to believe this is EPAC development tho.

06Z Apr 28
00Z April 28
18Z Apr 27
12Z Apr 27
06Z Apr 27
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting KoritheMan:


Climatological or not, that feature wasn't there before, to my knowledge.


I know but the ECMWF and most other models normally have an area of quasi-stationary 850 vort over the SW Caribbean and this is because of the flow around the Colombian Low which is a climatological feature for that region. But I could not tell whether it was a tropical cyclone or the low on the ECMWF because it was seen on the last frame so no movement could have been tracked.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
1756. HadesGodWyvern (Mod)
Joint Typhoon Warning Center

Tropical Disturbance Summary (0600z 28APR)
============================================
An area of convection (94W) located at 15.6N 123.6E or 125 NM east-northeast of Puerto Real, Philippines. Recent animated multispectral animation shows deep convective flaring associated with a tightly formed mid-level circulation center. A 2128z Quikscat Pass shows a strong shear line at the surface but an ambiguity analysis indicates covergent flow with limited cyclonic turning near the center. A 2313z SSMIS image shows weak convergent banding leading into deep convection near the center. Upper level analysis shows the system is located underneath the upper level ridge axis in an area of low vertical wind shear.

The maximum sustained winds near the center is 18-22 knots with a minimum sea level pressure of 1007 MB. The potential for this disturbance to form into a significant tropical cyclone within the next 24 hours is UPGRADED TO POOR.
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Quoting Weather456:
the area lacks model support except for a region of 850 mb vorticity on the 00Z EMCWF, but that maybe climatologically related.>


Climatological or not, that feature wasn't there before, to my knowledge.
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The GFS is now within 1 week. The chart below summarizes the ability of the GFS and other models to develop tropical and extratropical cyclones. As you may see the area lacks model support except for a region of 850 mb vorticity on the 00Z EMCWF, but that maybe climatologically related.

Member Since: July 24, 2005 Posts: 407 Comments: 19076
1753. HadesGodWyvern (Mod)
Tropical Cyclone Warning Center Darwin
High Seas (Gale Warnings)
TROPICAL LOW, EX-KIRRILY
4:30 PM CST April 28 2009
===============================

At 6:00 AM UTC, Tropical Low, Ex-Kirrily (1002 hPa) located at 5.8S 133.1E has 10 minute sustained winds of 30 knots with gusts of 45 knots. The low is reported as moving northwest at 4 knots.

Dvorak Intensity: T2.5/2.5/W0.5/24HRS

AREA AFFECTED
================
Within 60 nautical miles of the center.

Maximum winds of 30 knots near the center possibly increasing to 35 knots.

Forecast and Intensity
=======================
12 HRS: 5.7S 132.4E - 35 knots (CAT 1)
24 HRS: 5.8S 131.7E - 35 knots (CAT 1)
48 HRS: 7.0S 130.2E - 35 knots (CAT 1)
72 HRS: 8.6S 129.1E - 30 knots (TROPICAL LOW)

Additional Information
========================
TC Kirrily has weakened into a tropical low. Latest position fix is based on exposed LLCC evident in MTSAT VIS images. Convective structure has continued to weaken during the past 6 hours under moderate northeasterly wind shear. Curved peripheral cloud bands persist in the southwestern sector. Dvorak DT 2.5 based
on shear pattern with an exposed LLCC near the edge of deep cold cloud.

MET=PAT=2.5 and FT=2.5 based on a downward reassessment of the 0000UTC analysis. The system has moved slowly northwest under the influence of a strengthening low-level ridge to the SW. Mid-level steering is weak, with a short wave trough passing to the southeast and another forecast to develop over Western Australia within 48 hours. The consensus of model track forecasts indicates a west then
southwest track, if the system retains a deep circulation. Dry air to the north and west of the system centre is forecast to moisten during the forecast period and with southwest movement, the system may move into an area of reduced vertical wind shear. The intensity forecast indicates possible strengthening to
TC intensity early Wednesday as the low moves away from the influence of islands and towards a slightly more favourable environment.
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Well darn, I finally get time to get online tonight and everyone is gone! :o(
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Good evening everyone!
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good night,stay safe everyone!!!!...and sweet dreams of the gfs models at 300+hrs dancing in your heads....good night!!!!
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1749. KEEPEROFTHEGATE (Mod)
i even got the ac running 2nd day in a row we hit a high of 83.7 today 81.3 on saturday warmest day of the year so far with a lot more warm days to come although tomorrow its only get in the low 60's for highs with rain till early afternoon
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1748. KEEPEROFTHEGATE (Mod)
yeah still 68.9 here with humidex of 72.8 with rain and storms off to our west
Member Since: July 15, 2006 Posts: 170 Comments: 53603
are my friends up north ready for summer weather?????,I'll trade you,still 72 degrees at midnight down here....days are hot already,nights are perfect as long as there's a breeze(tonight there's a nice one!!!)gotta love it!!!!!!
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1746. KEEPEROFTHEGATE (Mod)
AWCN11 CWTO 272137
Weather summary for all of southern Ontario and
The national Capital region
Issued by Environment Canada Toronto at 5:33 PM EDT Monday 27 April
2009.

..The first confirmed tornado of the season for Ontario...

-------------------------------------------------------------
==weather event discussion==

After receiving reports of funnel clouds and a possible tornado in
the Windsor area Saturday evening, an Environment Canada damage
survey team was sent out earlier today. After speaking with some
eyewitnesses to the event and viewing the damage, Environment Canada
is confirming Ontario's first tornado of the 2009 season. The tornado
briefly occurred near the intersection of Hanna st east and langlois
avenue in Windsor. It did minor roof damage to a union hall and
Debris from the roof also did some damage to homes to the southeast
of the union hall. The tornado was rated as a Fujita scale zero event
with maximum winds around 90 kilometres per hour. This is the lowest
rating on the Fujita scale which goes from zero to five.
Environment Canada personnel are continuing to investigate damage
from Saturday's storms that occurred in the Ottawa area. Some of this
damage may also have been related to tornadoes. An update on this
investigation will be issued on Tuesday.
Saturday's storms were a reminder that the summer severe weather
season has now begun in southern Ontario. The season normally begins
in late April and lasts until early October. Severe thunderstorms can
produce large hail, heavy rain, damaging winds or tornadoes. At this
time of year it is always a good idea to stay informed about the
latest weather forecasts, watches and warnings. On days when severe
weather is possible, keep an eye on the sky and be prepared to seek
the most solid shelter available.

Member Since: July 15, 2006 Posts: 170 Comments: 53603
saw the hubble at around 9:10pm the last 2 nights ,pretty cool!!!!!
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Hmmm another east coast team bites the dust... Calgary... poof
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1742. KEEPEROFTHEGATE (Mod)
hello still waiting
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1741. KEEPEROFTHEGATE (Mod)
heres another flu map for tracking

Link
Member Since: July 15, 2006 Posts: 170 Comments: 53603
evening all!!!
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1739. KEEPEROFTHEGATE (Mod)
lol
Member Since: July 15, 2006 Posts: 170 Comments: 53603
Quoting CaneAddict:
For those in here..this is a useful map to track the latest Swine Flu cases..Night now!


View H1N1 Swine Flu

thanks bookmarked that in work today but didn't want to go through the HUNDREDS of post to find it again.
Member Since: Posts: Comments:
1736. hahaguy
Quoting SevereHurricane:


Good night good sir!


LOL
Member Since: August 12, 2007 Posts: 2 Comments: 2838
Quoting CaneAddict:
HAHA, If he can go to college and STUDY Tropical Meterology and still not know anything..then , I highly doubt he will be brilliant enough to change his IP. LMAO.

Night all!


Good night good sir!
Member Since: September 7, 2008 Posts: 17 Comments: 1604
For those in here..this is a useful map to track the latest Swine Flu cases..Night now!


View H1N1 Swine Flu
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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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