CSU and TSR predict an extremely active 2011 Atlantic hurricane season

By: Dr. Jeff Masters , 12:54 PM GMT on December 09, 2010

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A continuation of the pattern of much above-average Atlantic hurricane activity we've seen since 1995 is on tap for 2011, according to the latest seasonal forecast issued Wednesday by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). They are calling for 17 named storms, 9 hurricanes, and 5 intense hurricanes. An average season has 10 - 11 named storms, 6 hurricanes, and 2 intense hurricanes. The new forecast is a very aggressive one, since only six seasons since 1851 have had as many as 17 named storms; 19 seasons have had 9 or more hurricanes. The 2011 forecast calls for a much above-average chance of a major hurricane hitting the U.S., both along the East Coast (49% chance, 31% chance is average) and the Gulf Coast (48% chance, 30% chance is average). The Caribbean is forecast to have a 62% chance of seeing at least one major hurricane (42% is average.) Five years with similar pre-season November atmospheric and oceanic conditions were selected as "analogue" years that the 2011 hurricane season may resemble: 2008, 1999, 1989, 1961, and 1956. The average activity for these years was 12 named storms, 7 hurricanes, and 4 major hurricanes.

The forecasters cited several reasons for their forecast of a much above-average season:

1) Unusually warm sea surface temperatures continue in the tropical Atlantic this fall, an indication that the active hurricane period we have been in since 1995 will continue (in technical terms, the positive phase of the Atlantic Multidecadal Oscillation, AMO, will continue.) SSTs in Atlantic Main Development Region (MDR) for hurricanes, from the Caribbean eastwards to the coast of Africa, were at a record high in October (November data are not yet available.)

2) Hurricane activity in the Atlantic is lowest during El Niño years and highest during La Niña or neutral years. This occurs because El Niño events tend to increase westerly upper-level winds over the tropical Atlantic, bringing high wind shear harmful for hurricanes. The CSU team notes that we are currently experiencing moderate to strong La Niña conditions, with an unusual amount of cool water present in the top 300 meters of the Equatorial Pacific Ocean off the coast of South America. Since 1979, only eight years have had similar amounts of cool water in November. The hurricane seasons that followed each of those eight years were unable to transition to El Niño conditions. Thus, the CSU team expects that we will have neutral or La Niña conditions in place for the Atlantic hurricane season of 2011, which should act to keep wind shear values average to below average, enhancing hurricane activity. Of the 16 El Niño/La Niña computer models that made November predictions for the July-August-September 2011 portion of hurricane season (Figure 1), only 4 (25%) predicted that El Niño would arrive.

How accurate are the December forecasts?
The CSU real-time December forecasts did not shown any skill over the period 1992 - 2007, so the forecast scheme was overhauled and a new scheme implemented for the forecasts made for the 2008 - 2010 hurricane seasons. This new scheme showed some decent skill in those three years, with skill levels 18%, 10%, and 30% above chance for predicting the number of named storms, hurricanes, and intense hurricanes, respectively. Still, three years is too short of a time period to evaluate the skill of these December forecasts, and we should view the latest forecast as an experimental research product. Last year's December forecast for the 2010 hurricane season predicted 13.5 named storms, 7 hurricanes, and 4 intense hurricanes. The actual numbers were 19 named storms, 12 hurricanes, and 5 intense hurricanes.


Figure 1. Forecasts of El Niño conditions by 20 computer models, made in November 2010. The longest range forecasts for July-August-September (JAS) at the right side of the image show that 4 models predict weak El Niño conditions, 7 predict neutral conditions, and 5 predict a weak to moderate La Niña. El Niño conditions are defined as occurring when sea surface temperatures in the Equatorial Pacific off the coast of South America (the "Niño 3.4 region) rise to 0.5°C above average (top red line). La Niña conditions occur when SSTs in this region fall to 0.5°C below average. Image credit: Columbia University.

2011 Atlantic hurricane season forecast from Tropical Storm Risk, Inc.
The British private forecasting firm Tropical Storm Risk, Inc. (TSR), issued their 2011 Atlantic hurricane season forecast on Monday. They are also calling for a very active year: 15.6 named storms, 8.4 hurricanes, and 4 intense hurricanes. TSR predicts a 66% chance of an above-average hurricane season, 22% chance of a near-normal season, and only a 12% chance of a below normal season. TSR bases their December forecast on predictions that sea surface temperatures next fall in the tropical Atlantic will be above about 0.3°C above average, and trade wind speeds will be about 0.7 m/s slower than average. The trade wind speed prediction is based on a forecast for a weak La Niña in August-September 2011.

I like how TSR puts their skill level right next to the forecast numbers: 2% skill above chance at forecasting the number of named storms, 1% skill for hurricanes, and 7% skill for intense hurricanes. That's not much skill, and really, we have to wait until the June 1 forecasts by CSU, NOAA, and TSR to get a forecast with reasonable skill.

Comparing 2005 and 2010 steering currents
The U.S. got extremely fortunate during the 2010 hurricane season that the steering currents carried most of the storms out to sea, or forced them to the south. A very graphic way of looking at this is to compare the amount of rain that fell due to tropical cyclones in the Atlantic in 2005 versus 2010 (Figure 2.) The U.S. received a direct hit only from Tropical Storm Bonnie, which hit South Florida as a minimal 40 mph tropical storm and caused no significant damage. TSR is predicting that this luck will not hold in 2010; they project that five named storms will hit the U.S., with two of these being hurricanes.


Figure 2. Rainfall amounts due to all Atlantic tropical cyclones in 2005 and 2010, as measured by NASA's TRMM satellite. Steering currents in 2010 tended to recurve many storms out to sea between the Caribbean and Bermuda, due to a large number of unusually strong troughs of low pressure moving off the U.S. East Coast.

Weekend winter storm for Eastern U.S.
The latest 06Z (1am EST) set of computer model forecasts for this weekend's winter storm over the Midwest and Eastern U.S. point towards a more northerly path for the storm, bringing the axis of heaviest snow through Wisconsin and Michigan. There is still a great deal of uncertainty in the predicted timing and strength of the storm, but a renewed blast of cold air Monday and Tuesday over the Southeast U.S. is still highly likely in the wake of the storm.

Jeff Masters

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Quoting Floodman:


EXACTLY! Watch yourself though...now you've admitted there is a problem, the deniers will be coming for you...LOL
Good evening FloodMan... Cold up here....:)
Member Since: September 27, 2007 Posts: 1 Comments: 21193
Quoting P451:



The only thing I see here is that it would appear the climate is in a stage of warming and it would seem Man's emmissions have helped to accelerate that warming, but man is not the CAUSE of that warming.


EXACTLY! Watch yourself though...now you've admitted there is a problem, the deniers will be coming for you...LOL
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Quoting pilotguy1:
What is the "ideal" temperature of the Earth?
what's the ideal passive aggressive fallacious ploy?
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Quoting pilotguy1:
What is the "ideal" temperature of the Earth?
When the trout will bite!
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Quoting largeeyes:
TSR is predicting that this luck will not hold in 2010; they project that five named storms will hit the U.S., with two of these being hurricanes.


I think you mean 2011.


See post 52
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"...1) Rapid climate change is the prime suspect in most mass extinction events, including the Great Dying some 250 million years ago, in which 90% of all life went extinct. That's one downside..."

Wait a minute - there was a rapid rise in temperatures 250 million years ago?

And it killed off 90% of all life?

What brought that on, a massive burning of fossil fuels by man? Or was there another source of natural CO2 that drove that unprecedented warming?
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TSR is predicting that this luck will not hold in 2010; they project that five named storms will hit the U.S., with two of these being hurricanes.


I think you mean 2011.
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Not sure what this may bring to the East coast but Southern Wisconsin looks to be in the bulls eye for a snow event -


MEANWHILE...A SECOND AND POTENTIALLY MORE INTENSE STORM WILL
LIKELY TRACK ACROSS IOWA AND NORTHERN ILLINOIS SATURDAY BEFORE
MOVING INTO LOWER MICHIGAN SATURDAY NIGHT. THERE HAS BEEN QUITE A
BIT OF UNCERTAINTY IN THE TRACK OF THIS STORM. THE MOST LIKELY
TRACK NOW APPEARS TO FAVOR HEAVY SNOW GENERALLY ALONG AND NORTH OF
A LINE FROM MINERAL POINT TO MADISON...BEAVER DAM...AND SHEBOYGAN.
THE PRECIPITATION MAY BEGIN AS A PERIOD OF FREEZING RAIN OR SLEET. DEPENDING
ON THE TRACK...LESSER AMOUNTS OF SNOW ARE EXPECTED ALL THE WAY TO
THE ILLINOIS BORDER.

WIZ046-047-051-052-056>059-063-100400-
/O.NEW.KMKX.WS.A.0005.101211T1200Z-101212T1200Z/
/O.CON.KMKX.WW.Y.0005.101209T2100Z-101210T0600Z/
MARQUETTE-GREEN LAKE-FOND DU LAC-SHEBOYGAN-SAUK-COLUMBIA-DODGE-
WASHINGTON-DANE-
INCLUDING THE CITIES OF...MONTELLO...BERLIN...FOND DU LAC...
SHEBOYGAN...BARABOO...PORTAGE...WISCONSIN DELLS...BEAVER DAM...
WEST BEND...MADISON
107 PM CST THU DEC 9 2010

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT CST
TONIGHT...
...WINTER STORM WATCH IN EFFECT FROM SATURDAY MORNING THROUGH
LATE SATURDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN MILWAUKEE/SULLIVAN HAS ISSUED A
WINTER STORM WATCH...WHICH IS IN EFFECT FROM SATURDAY MORNING
THROUGH LATE SATURDAY NIGHT. A WINTER WEATHER ADVISORY REMAINS IN
EFFECT UNTIL MIDNIGHT CST TONIGHT.

* TIMING...SNOW WILL BEGIN TO ACCUMULATE EARLY IN THE AFTERNOON
FROM MADISON WESTWARD...AND BY MID TO LATE AFTERNOON ELSEWHERE
IN SOUTHERN WISCONSIN.

ANOTHER ROUND OF SNOW IS EXPECTED SATURDAY AND SATURDAY NIGHT.
A PERIOD OF FREEZING RAIN OR SLEET IS POSSIBLE EARLY SATURDAY
BEFORE CHANGING TO ALL SNOW.

* SNOW ACCUMULATIONS...2 TO 4 INCHES ARE EXPECTED WITHIN THE
ADVISORY AREA WITH THE HIGHEST AMOUNTS NORTH OF A PORT
WASHINGTON TO PORTAGE LINE.

AN ADDITIONAL 6 TO 10 INCHES OF SNOW IS POSSIBLE WITH THE SECOND
STORM SATURDAY AND SATURDAY NIGHT.
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thoughts on the storm to affect the Northeast next week: Link
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I really don't c a warm-up after this weekend into monday.. It shows -nao looks extremely west based.. So probably into early January from what I can tell is that we could see the same pattern, so that means more southern systems and maybe mix with frozen precipitation for parts of the south.. So probably more lake effect snow and snow mid atl to the northeast.. But thats what I got from some models as for now.. It could change and of course, they do.. I say if that -nao changes then most likely other scenarios will change.. JMO
Member Since: August 15, 2008 Posts: 0 Comments: 2133
today's blog circus is not entirely ridiculous... but i see a lot of half ***ed points made with little imagination or understanding of the science behind the science.

most people quit thinking once they've found their appropriated answer. sad.
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low level clouds have returned in vengence on the TX coast. From freezing and frosty with clear skies, I haven't seen such a return flow of clouds this quick that I can remember.
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Quoting Patrap:
As a rule,

I usually refer to Floodman or Grothar for anything past the Cretaceous Period.





rofl! Pat now that is funny!
Member Since: August 29, 2005 Posts: 298 Comments: 40902
Quoting McBill:


Ice ring??? I do think it's telling that you apparently don't have a clue as to how past temperature data is estimated from ice cores. Nothing to do with "ice rings," whatever they are, but rather derived from a ratio of 2 oxygen isotopes. If you care to educate yourself, you can try Paleoclimatology: The Ice Core Record.





please share in laymans terms.....
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Quoting P451:



I have a simple response:

Is a thin ice ring due to a warm winter or is it due to a dry winter? It may have been very warm and rainy thus a thin ice ring. It also might have been very cold and dry thus a thin ice ring.

Is it a thick ice ring due to a cold winter or is due to a very wet winter? It may have been very cold and everything fell as snow thus a thick ice ring. It could have also been very warm yet cool nenough for snow and wet thus a thick ice ring.


When you can extrapolate the difference (which nobody can) then you can cite ice cores as evidence to support "Global Warming" until then they are no more than something of interest of which we don't have the ability to do any more than claim that it was a LOW PRECIPITATION SEASON.

I do not feel that you can extract a temperature record from these. Let alone use them as a basis for suggesting "AGW". You can't use those as a benchmark let alone a foundation.





That was a spectacular analogy.
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AMY!!!!!!
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Party Time!! Woo Hoo!!!

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Quoting P451:



The only thing I see here is that it would appear the climate is in a stage of warming and it would seem Man's emmissions have helped to accelerate that warming, but man is not the CAUSE of that warming.

Well, you're correct, techincally-speaking; the sun is the cause of all warming; the heat it gives off is being increasingly trapped by GHGs. But that's a little like saying smoking isn't the cause of most lung cancers; cigarettes are. ;-)

I'm out for several hours. I only announce that because I know some will be happy to hear it. ;-)
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Quoting jiminceiba:
ok..assume that the planet is warming...and not just a typical inter-glacial warming...what is the down side?
seems to me, we have greenland, northern canada, and russia/siberia thawing out....isn't that like most of the land mass on earth...so..the great plains in all continents expand like 400%

just conjecture...but..glass half full?

and another thing..this dissin america is kinda moot...considering that china is one big smoking coal fired tailpipe....rip them...see what happens...grin..they will tell the world to punch sand

Two things:

1) Rapid climate change is the prime suspect in most mass extinction events, including the Great Dying some 250 million years ago, in which 90% of all life went extinct. That's one downside. ;-)

2) China, far more than the United States, is working quickly and feverishly on ways to mitigate global warming. Yes, they have a lot of catching up to do--but they realize far more than does the US that the current fossil fuel paradigm is unsustainable. And they're working on getting their future engineers and scientists ready for it; did you see the results of the PISA test scores released this week? The United States scored 25th among 34 developed nations on standardized tests given to 15-year-olds (or 18th when the scores were weighted). Meanwhile, the Shanghai region China came out on top. The US came in behind Hungary and Poland in science; we tail Estonia and Hong Kong in reading; and we're near the bottom in math, ranking behind countries such as Slovakia and the Czech Republic. Sure, it's an imperfect metric, but facts are facts: the Chinese will be the technological leaders in cleaner energy. That's not "dissin'"; that's just the truth.
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Okay I would like to apologize to all floridians for my comment yesterday for not liking the cold weather,and complaining/over reacting about it.So yes I may not understand compleatly.Oh and my co-worker says hello.
Member Since: August 14, 2010 Posts: 10 Comments: 16971
103. N3EG
TSR is predicting that this luck will not hold in 2011; they project that five named storms will hit the U.S., with two of these being hurricanes.

2010 was the year of the westcaster... 2011 will be the year of the OVERDUEcaster.
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The CSU team notes that we are currently experiencing moderate to strong La Nia conditions, with an unusual amount of cool water present in the top 300 meters of the Equatorial Pacific Ocean off the coast of South America. Since 1979, only eight years have had similar amounts of cool water in November. The hurricane seasons that followed each of those eight years were unable to transition to El Nio conditions.
I thought this was interesting, quoted from Masters blog post.

Were most of these instances before 1995 or after?
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Quoting tornadodude:


valid answers, Im not trying to be argumentative, more so inquisitive.

Im not convinced that man is the sole reason the earth is warming, however, I don't think we are having any type of cooling effect either. Keeping an open mind.


You say you're done with this topic, so no response is required. That's fine; I'll post this for others who may be interested.

Earth's CO2 levels have fluctuated in the past, rising and falling between about 180ppm to 300ppm. The thing is, these swings have all taken over times spans of 5,000 to 20,000 years. In comparison, CO2 levels have risen by more than 100ppm in just the last 150 years--and isotopic signatures show that the recent rise is due primarily to the burning of fossilized hydrocarbon deposits. Those are unassailable facts. And given that rising CO2 levels, while not the only cause of climate change, are the only way to explain the recent warm up that's been concurrent with rising CO2 levels, scientists are left with no other way to explain what's going on. Mountains of observation, data, and modelling agrees.

TTYL...
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ok..assume that the planet is warming...and not just a typical inter-glacial warming...what is the down side?
seems to me, we have greenland, northern canada, and russia/siberia thawing out....isn't that like most of the land mass on earth...so..the great plains in all continents expand like 400%

just conjecture...but..glass half full?

and another thing..this dissin america is kinda moot...considering that china is one big smoking coal fired tailpipe....rip them...see what happens...grin..they will tell the world to punch sand
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Quoting Neapolitan:

Precisely. But while it's one thing to debate what color dinosaurs were or whether they had feathers, it something else entirely to deny their very existence. My point is that the data which overwhelmingly show that the planet is warming rapidly in the past few decades are every bit as conclusive to expert climate scientists as a T. Rex bone is to a paleontologist.
I would agree. Anyone who dismisses the proxy data that they use to reconstruct past climates is being untruthful. However, my point, which I think you understand, is that it's still an inference and that this small issue injects an element of doubt into the deniers mind. When you're a denier even the smallest hint of a doubt or limitation is all that's necessary to deny. It's like a small crack destroys the massive block of granite by default. It's unlikely this little crack will break the block, but a denier doesn't know that.
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Quoting Patrap:
As a rule,

I usually refer to Floodman or Grothar for anything past the Cretaceous Period.





LOL that's great
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86. Patrap 10:53 AM PST on December 09, 2010
As a rule,

I usually refer to Floodman or Grothar for anything past the Cretaceous Period.




hahahahahahahahahahahahaha!!!!

:)
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Quoting Patrap:
As a rule,

I usually refer to Floodman or Grothar for anything past the Cretaceous Period.





LOL

Careful, Patrap. I hear tales that Grothar still has a mastodon hanging around and it has quite a temper. I might need to mention that Grothar hand feeds it. Grothar is the only person that the mastodon likes. They've hung out together for YEARS.
Member Since: August 24, 2010 Posts: 0 Comments: 4737
Global Warming
Frequently Asked Questions
National Oceanic and Atmospheric Administration
National Climatic Data Center


*
1. What is the greenhouse effect, and is it affecting our climate?
2. Are greenhouse gases increasing?
3. Is the climate warming?
4. Are El Niños related to Global Warming?
5. Is the hydrological cycle (evaporation and precipitation) changing?
6. Is the atmospheric/oceanic circulation changing?
7. Is the climate becoming more variable or extreme?
8. How important are these changes in a longer-term context?
9. Is sea level rising?
10. Can the observed changes be explained by natural variability, including changes in solar output?
11. What about the future?

Member Since: July 3, 2005 Posts: 424 Comments: 128273
Quoting Neapolitan:

Solidity of evidence is in the eye of the beholder, I suppose, but the fact that a layperson doesn't understand the science behind a particular piece of data doesn't invalidate that data; scientists know what it means, and that's what really matters. I like to think I'm a smart guy, but when it comes to, say, the finer points of quantum mechanics, I'm at a loss, so I defer to folks like Einstein and Hawking; we can't all be experts in every area, you know? And you're right: a lot of those who believe in the theory of AGW don't know exactly how isotopic analyses of glacial ice cores work. But do they really need to? After all, I don't need to be an ASE-certified master mechanic to know what it means when the auto repair shop says my truck needs a valve job.

Answering your analogy: without knowing all the details, it would be hard to tell why the footprint was wet. The problem is, we've got many people at this moment disagreeing that a footprint even exists... ;-)


valid answers, Im not trying to be argumentative, more so inquisitive.

Im not convinced that man is the sole reason the earth is warming, however, I don't think we are having any type of cooling effect either. Keeping an open mind.

and also done with posts about this topic.

back to the current weather :PP

its finally above freezing for the first time in 6 days here ha
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As a rule,

I usually refer to Floodman or Grothar for anything past the Cretaceous Period.



Member Since: July 3, 2005 Posts: 424 Comments: 128273
Quoting paratomic:
It's still an inference. Take for example, the actual appearance of dinosaurs. We probably don't get the color right. And in many cases we do not know for sure whether a dinosaur had feathers or not because the absence of feather fossils or certain anatomy doesn't rule out feathers. To illustrate, this is what wikipedia says the Velociraptor Mongoliensis looked like:


And they didn't have this evidence before 2007 even though they suspected that it had a lot in common with modern birds (descendants of dinosaurs). So this is only the latest conception of what a raptor looked like. What else will we uncover in the coming years? Maybe it's not perfect. How do we know?

Notice how it looks wildly different than what we saw in jurassic park.

Even the Deinonychus looks different, despite that it's a similar size and is probably dangerous too (just not the same, nor as fast and not as smart as the ones in the movie):


Until we have actual video from that time and actual recordings, it can only be an inference. That doesn't mean it's not reliable, it just will always give deniers an element of doubt to hold onto.

Precisely. But while it's one thing to debate what color dinosaurs were or whether they had feathers, it something else entirely to deny their very existence. My point is that the data which overwhelmingly show that the planet is warming rapidly in the past few decades are every bit as conclusive to expert climate scientists as a T. Rex bone is to a paleontologist.
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Quoting tornadodude:


Ive been staying out of the debate, but I fail to see how finding a fossil is similar to being able to tell what the temperature was by using ice records, etc. A fossil is pretty solid proof of something's existence, and is relatively easy to understand. However, the ice core readings and other terms get thrown around so loosely that a lot of AGW believers probably don't know how they even use ice to find out the temperatures from thousands and thousands of years ago.

If I find a footprint in the sand, and it is still wet, is it because it has been wetter than normal due to human-induced warming causing more rainfall? or simply because of a natural reason, such as high tide?

Solidity of evidence is in the eye of the beholder, I suppose, but the fact that a layperson doesn't understand the science behind a particular piece of data doesn't invalidate that data; scientists know what it means, and that's what really matters. I like to think I'm a smart guy, but when it comes to, say, the finer points of quantum mechanics, I'm at a loss, so I defer to folks like Einstein and Hawking; we can't all be experts in every area, you know? And you're right: a lot of those who believe in the theory of AGW don't know exactly how isotopic analyses of glacial ice cores work. But do they really need to? After all, I don't need to be an ASE-certified master mechanic to know what it means when the auto repair shop says my truck needs a valve job.

Answering your analogy: without knowing all the details, it would be hard to tell why the footprint was wet. The problem is, we've got many people at this moment disagreeing that a footprint even exists... ;-)
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La nina forecast to strenghen:

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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.