Amazon rainforest recovering from its second 100-year drought in 5 years

By: Dr. Jeff Masters , 2:32 PM GMT on December 03, 2010

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Life-giving rains have returned over the past two months to Earth's greatest rainforest--the mighty Amazon--after it experienced its second 100-year drought in five years this year. The record drought began in April, during the usual start to the region's dry season, when rainfall less than 75% of average fell over much of the southern Amazon (Figure 2.) The drought continued through September, and by October, when the rainy season finally arrived, the largest northern tributary of the Amazon River--the Rio Negro--had dropped to thirteen feet (four meters) below its usual dry season level. This was its lowest level since record keeping began in 1902. The low water mark is all the more remarkable since the Rio Negro caused devastating flooding in 2009, when it hit an all-time record high, 53 ft (16 m) higher than the 2010 record low. The 2010 drought is similar in intensity and scope to the region's previous 100-year drought, which hit the Amazon in 2005, according to Brazil's National Institute of Space Research. Severe fires burned throughout the Amazon in both 2005 and 2010, leading to declarations of states of emergencies.


Figure 1. Hundreds of fires (red squares) generate thick smoke over a 1000 mile-wide region of the southern Amazon rain forest in this image taken by NASA's Aqua satellite on August 16, 2010. The Bolivian government declared a state of emergency in mid-August due to the out-of-control fires burning over much of the country. Image credit: NASA.

Causes of the great 2010 Amazon drought
During the 20th Century, drought was a frequent visitor to the Amazon, with significant droughts occurring an average of once every twelve years. These droughts typically occurred during El Niño years, when the unusually warm waters present along the Pacific coast of South America altered rainfall patterns. But 2010 was a La Niña year. The 100-year drought of 2005 occurred in an El Niño-neutral year. Subsequent analysis of the 2005 drought revealed that it was unlike previous El Niño-driven droughts, and instead was caused by record warm sea surface temperatures in the Atlantic (Phillips et al., 2009.) These warm ocean waters affected the southern 2/3 of the Amazon though reduced precipitation and higher than average temperatures. Very similar record Atlantic sea surface temperatures were observed in 2010, and likely were the dominant cause for the 2010 drought.


Figure 2. The great Amazon drought of 2010 began in April, when portions of the southern Amazon recorded precipitation amounts less than 75% of normal (brown colors). The drought spread northward and peaked during July and August, but drew to a close by November when the rainy season began. Image credit: NOAA Climate Prediction Center.

The importance of the Amazon to Earth's climate
We often hear about how important Arctic sea ice is for keeping Earth's climate cool, but the Amazon may be even more important. Photosynthesis in the world's largest rainforest takes about 2 billion tons of carbon dioxide out of the air each year. However, in 2005, the drought reversed this process. The Amazon emitted 3 billion tons of CO2 to the atmosphere, causing a net 5 billion ton increase in CO2 to the atmosphere--roughly equivalent to 16 - 22% of the total CO2 emissions to the atmosphere from burning fossil fuels that year. According to Phillips et al., 2009, "The exceptional growth in atmospheric CO2 concentrations in 2005, the third greatest in the global record, may have been partially caused by the Amazon drought effects documented here." The Amazon stores CO2 in its soils and biomass equivalent to about fifteen years of human-caused emissions, so a massive die-back of the forest could greatly accelerate global warming. In late 2009, before the 2010 drought, the World Wildlife Federation released a report, Major Tipping Points in the Earth's Climate System and Consequences for the Insurance Sector, which suggested that odds of extreme 2005-like droughts in the Amazon had increased from once every 40 - 100 years, to once every 20 years. The study projected that the extreme droughts would occur once every two years by 2025 - 2050. This year's drought gives me concern that this prediction may be correct. The occurrence of two extreme droughts in the past five years, when no El Niño conditions were present and record warm Atlantic sea surface temperatures occurred, are suggestive of a link between global warming and extreme Amazon drought. If the climate continues to warm as expected, the future health of Earth's greatest rainforest may be greatly threatened, and the Amazon may begin acting to increase the rate of global warming. According to Rosie Fisher, a scientist at the National Center for Atmospheric Research in Boulder, Colorado who specializes in interactions between climate and forests, "I'm genuinely quite alarmed by this. In some ways it kind of reminds me of when they figured out than the Greenland ice sheet was melting much faster than the climate models predicted it would."

Deforestation in Brazilian Amazon falls to lowest rate on record
There is some good news from the Amazon--deforestation rates in the Brazilian Amazon have fallen 14% in the past year, and are at their lowest rate on record, according to mongabay.com, an environmental science and conservation news site that focuses on tropical forests. In 2009, Brazil passed a law committing to a 36 - 39% reduction in emissions of greenhouse gases. Reducing deforestation by 80% by 2020 was the primary method envisioned to achieve the reduction. Brazil is now four years ahead of that schedule, and no longer is the world's biggest deforester--Indonesia now cuts down more acreage of forest each year than Brazil does.

For more information
Nick Sundt at the WWF Climate Blog has a remarkably detailed post on this year's Amazon drought, and Dr. Joe Romm at climateprogress.org has another excellent post.

Phillips, et al., 2009, Drought Sensitivity of the Amazon Rainforest, Science 6 March 2009: Vol. 323 no. 5919 pp. 1344-1347 DOI: 10.1126/science.1164033.

I'll have new post Monday or Tuesday.

Jeff Masters

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Keep in mind that August in Bolivia, being a southern hemisphere country, is usually one of its colder months. The coolest months of the year in La Paz, the capital of Bolivia are usually June and July.
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Quoting Grothar:


I used to love cantore before he became this big celebrity and so full of himself.

Quoting johnnyascat:







THanks for posting the hurricane season loop. Cool to look back on these storms in the MDR all at once. Interesting music. My favorite part has to be 6 to 7. Matthew - a classic cape verde storm moving across the carribean and developing just before landfall. Then the remnants of that were drawn back east into Nicole-easter. then the remaining moisture sitting in the carribean was drawn northeast into a ULL and caused it to transition in an absolutely textbook fashion into Otto. I love watching STS form and they always seem to form exactly the same. The moisture wraps around the circluation once, then it breaks from the front, then convection bursts over the center as it becomes tropical.
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Quoting DoverWxwatchter:
Thundersnow is not that rare.  It happens in a lot of strong snow bands in east coast storms.  Of course the lightning in heavy snow is almost impossible to see, and heavy snow in the air muffles the thunder.

Back in Feb 2006 when NYC had their record snow, there was a lot of lightning over the city when the heaviest snowband set up over Manhattan.


The most prominent thundersnow event in my memory in Southern Ontario was the storm of December 14, 2001. There may have been another one in the winter of 2004-05.
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Yes, I did in fact predict this Amazon drought earlier in the year, when indicators of a warm Caribbean for the hurricane season led to the conclusion that the Western Hemisphere Warm Pool pattern will set up for higher precipitation over the Caribbean and a drought for the Amazon Basin. Fires and drought hit Bolivia and Brazil. Meanwhile, flooding still continues in Colombia and Venezuela.

Now, La Nina is setting in. It will be interesting to finally find a clear link between the NAO/AO/PNA, PDO/ENSO/AMO and the Amazon-Caribbean-US Midwest pattern in the climate and how one affects the other. If we can do that, understanding the oscillations will be much easier and the anthropogenic factor in climate fluctuations can be more clearly isolated.

Here in S. Ontario, the snowsqualls from the previous day continue melting. Still no sign of the 2-3 ft of snow predicted by AccuWeather.
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I took a Paleoclimatology corse some years back. I was particularly interested in learning the mechanisms behind the Milankovitch Cycles of the recent (several million years) past. I wanted to look at a period of time in which the continents are prett much where they are today and solar output constant.

I was struck by how a rather subtle change in the DISTRIBUTION od solar insolation cound trigger glaciations/deglaciations. The xplanation as I finally (sort of) figured it out relied on feedback loops - carbon and albedo. Looking at today's climate change I see these mechanisms being 'turned on their head' with man-made CO2 increases triggering temperature increase, climate pattern changes, and then both albedo reduction and further CO2 incrases.

I have seen the term "super-interglacial" used to describe where we are heading. CO2 levels today are 'more greater' than a normal interglacial than an interglacial is greater than a glacial period. Unlike a normal cycle in which temperature/albedo drives CO2 (and then feedbacks) we are now seeing the rverse - CO2 is driving temperature (and feedbacks).

Today we have been discussing the possible breakdown of Amazonia as our lungs. Acidification of the oceans is also reducing 'primary productivity' of phytoplankton. This can lead to a reduction of CO2 uptake there as well. I fear that these changes are occurring much more rapidly than ecosystems can adapt to.

We are seeing and will continue to see various tipping points passed. I fear that the most 'pessimistic' profections of climate change will be proven to be too OPTIMISTIC.
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Quoting Grothar:


They were tought little critters, but no match for a Viking. How you doing Some1?


I am doing fine, sir. How are you doing today?
Member Since: August 24, 2010 Posts: 0 Comments: 4737
RE: Neapolitan's thundersnow post.

While watching TWC several years back, Jim Cantore experienced this same phenomenon while reporting live from the field. I believe it too was in the Buffalo area.
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What's this? Some snow? Snow that will hit Cincinnati and bring 2-3 inches? I think so!
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For my area in Destin,FL..

Long term (monday through thursday)...large upper trough over the
eastern Seaboard will allow a cold dome of surface high pressure to build
south out of the upper plains sates early Monday and into the
southeastern sates by early Thursday. With this...very cool/cold
pattern will continue...with below normal temperatures expected
through the period. Daytime highs will generally be in the 50s...with
overnight lows ranging from the lower 20s over interior zones to the
low/middle 30s along the coast. Although surface high pressure will be
building over the area...models (gfs and ecmwf) are indicating an
upper level disturbance will move through the base of the large upper
trough sometime around Tuesday night
. For now will just mention an
increase in clouds in forecast as we wait for later model runs to better
define this.


It would be nice if it is something like snow..
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Quoting DoverWxwatchter:
Droughts get worse in the Amazon due to deforestation because of less evapotranspiration from trees.   And trees do not have net emissions of CO2 until they die and rot.  Before death, all trees are net absorbers of CO2, not emitters.



So, I was 100% wrong? It sounded so smart in my head, haha. Like I said, I don't follow this type of stuff, I just find it somewhat interesting and wanted to post my opinion, even though it turned out to be fact and wrong. Thanks for clearing that up though.
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Quoting MiamiHurricanes09:
I really like Jon Gruden, but since apparently no "real talk" is going on, Dan Mullen would be the next best thing.


Gruden said the other day he was commited to ESPN. Shame too, I always thought he was a good coach.
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Quoting xcool:


snow for me la

hey xcool.. would love some snow soon.. that would be nice..
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Woohoo here comes the snow! Winter Weather Advisory and 2" to over 4" expected! Think my area is a solid 3"+. I'm digging out the sleds:)
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Great post Dr. M. It's nice to know that there are facts that prove it's not JUST humans causing global warming, to keep those environmental nuts like Al Gore in check. It's really ironic, so what I gather is the extreme deforestation actually HELPED slow global warming, because during these droughts there were less trees to emit CO2? But maybe these extreme droughts are somehow caused by the deforestation. It's all very confusing which is why I don't get into environmentalism and the related politics, but I do find it interesting.
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Quoting xcool:


snow for me la
Wow. It actually is enough of a chance to make it into the NWS forecast. Interesting.

Would this be the 4th year in a row we had *some* snowfall in SE LA?!? When we would usually go 10 years in between snowfall? More interesting.
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Quoting Neapolitan:

Oh, boy. Denial is such a funny, funny thing, isn't it? Faced with overwhelming evidence of a climate shift, the default contrarian position is to claim the evidence is wrong--and when that tack fails, they fall back to position #2: the evidence doesn't exist at all. (Position #3 says the evidence doesn't cover enough time; #4 says the evidence, even if it does exist, doesn't matter. And so on...)

When a particular scientific theory is offered, and when nearly every piece of credible observational data supports that theory, and when virtually no data supports any other theory, it's only the fool who refuses to see the truth.
??? What does this have to do with water levels in a river basin that changes with man's addition of hydroelectric dams?

Just sayin that the river level doesn't say all that some would like to say it is...
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snow for me la
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geoffrey wpb yep a freeze watch
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Quoting MiamiHurricanes09:
I really like Jon Gruden, but since apparently no "real talk" is going on, Dan Mullen would be the next best thing.


That's true. They don't really need anyone with ties to the program coming in and coaching.
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Quoting caneswatch:


What i'm saying! Who are you hoping will be the next coach?
I really like Jon Gruden, but since apparently no "real talk" is going on, Dan Mullen would be the next best thing.
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Quoting MiamiHurricanes09:
At least they got Shannon out of there...


What i'm saying! Who are you hoping will be the next coach?
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From the Miami NWS Disccussion:

BY LATE SUNDAY, THE LEADING EDGE OF THE ARCTIC AIRMASS WILL MOVE
ACROSS S FLA WITH THIS COLD AIR CONTINUING TO FUNNEL SOUTH FOR MUCH
OF THE UPCOMING WEEK. AS THE CAA TAKES SHAPE, THIS WILL CONTINUE A
NORTH TO NORTHWEST WIND OF AROUND 5 TO 10 MPH SUNDAY NIGHT/EARLY
MONDAY MORNING WHICH WILL GENERATE WIND CHILLS RANGING FROM THE MID
30S ACROSS GLADES COUNTY TO AROUND 40 MUCH OF INTERIOR ZONES AND MID
40S ALONG BOTH THE WEST AND EAST COASTS. BOTH THE GFS AND ECMWF ARE
NOW COMING MORE TO A CONSENSUS THAT THE COLDEST AIR WILL ARRIVE
TUESDAY MORNING AND POSSIBLY CONTINUE THROUGH THURSDAY AS THE
NORTHWEST FLOW BECOMES PERSISTENT. THIS WILL USHER IN THE COLDEST
AIR THUS FAR THIS SEASON AND FREEZING TEMPERATURES ARE POSSIBLE OVER
MUCH OF SOUTH FLORIDA AWAY FROM THE COASTAL REGIONS. WHAT MAKES THIS
PATTERN SO UNUSUAL FOR S FLA IS THAT IT COULD BE A FREEZE EVENT FOR
THREE CONSECUTIVE MORNINGS. SINCE THIS IS BECOMING MORE CONCLUSIVE
THAT A FREEZE WILL OCCUR FOR AT LEAST SOME PART OF S FLA, A FREEZE
OUTLOOK WILL BE ISSUED THIS AFTERNOON.
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Quoting Dakster:
MH09 - I hear they are renaming the University of Miami Football team to the Miami Tropical Depression after last weeks game...
At least they got Shannon out of there...
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Quoting Dakster:


LOL... and EvPv - Dr. Masters "pratices" what he preaches.


I don't know what was funnier, Dr. Master's retort or melwerle's comment.
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Quoting Dakster:
MH09 - I hear they are renaming the University of Miami Football team to the Miami Tropical Depression after last weeks game...


Now that is cold!!!!!! Keeping warm Dak?
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MH09 - I hear they are renaming the University of Miami Football team to the Miami Tropical Depression after last weeks game...
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Quoting Some1Has2BtheRookie:


That is very impressive, Grothar. I love what you did with the curtains! Is the blanket from your pet mastodon?

Good to see you today, Grothar.


They were tought little critters, but no match for a Viking. How you doing Some1?
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Quoting heavyweatherwatcher:
Hey Grothar,
I've been to "surprisingly mild" Bergen several times... and yes, for being nearly polar, I could guess it's mild... but in absolute terms... its friggin cold, wet, and white in the winter... though they do serve great meat cooking on a hot rock there(pork, beef, lamb, and horse)!



Yes, and they talk a funny Norwegian dialect in Bergen, too! LOL Here is a little snippet I thought I would share. They are having a very cold year so far. Broke all records.


Because of the North Atlantic Drift, Norway has a mild climate for a country so far north. With the great latitudinal range, the north is considerably cooler than the south, while the interior is cooler than the west coast, influenced by prevailing westerly winds and the Gulf Stream. Oslo's average yearly temperature ranges from a about 5° C (41° F ) in January to 28° C (82° F ) in July. The annual range of coastal temperatures is much less than that of the continental interior. The eastern valleys have less than 30 cm (12 in) of rain yearly, whereas at Haukeland in Masfjord the average rainfall is 330 cm (130 in).



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Quoting Grothar:


Yo! Canes. It is cold here already. Would like it around Christmas though.


Yeah, I would love a cold Christmas, hopefully it will happen. We haven't had a cold christmas in a while.
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Quoting Grothar:
Since I lived in both Greenland, Norway,(as well as a few other places, it may surprise some to know that coastal Norway has a surprisingly mild climate. While the interior sections, especially in the North has very cold and snowy climates, that is not the case on the coast. We do not live in igloos and are snowbound 11 months of the year. We even swim in the fjord regions.

If you don't believe me, here is a picture of my bedroom



That is very impressive, Grothar. I love what you did with the curtains! Is the blanket from your pet mastodon?

Good to see you today, Grothar.
Member Since: August 24, 2010 Posts: 0 Comments: 4737
Quoting caneswatch:


Hey Grothar, I heard we may be getting some 20s around here.


Yo! Canes. It is cold here already. Would like it around Christmas though.
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miami hurricanes 2009 we are going into the 30 and a freeze watch
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Quoting Grothar:


I can't laugh and choke at the same time; I am too old .


LOL... and EvPv - Dr. Masters "pratices" what he preaches.
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DON'T YOU GUYS HATE WHEN THIS HAPPENS?

Link
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Not looking good for Levi up in Fairbanks, Alaska with the temperature currently a frigid -3˚F. Massive trough of low pressure affecting him...



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Hey Grothar,
I've been to "surprisingly mild" Bergen several times... and yes, for being nearly polar, I could guess it's mild... but in absolute terms... its friggin cold, wet, and white in the winter... though they do serve great meat cooking on a hot rock there(pork, beef, lamb, and horse)!
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Quoting Grothar:
Since I lived in both Greenland, Norway,(as well as a few other places, it may surprise some to know that coastal Norway has a surprisingly mild climate. While the interior sections, especially in the North has very cold and snowy climates, that is not the case on the coast. We do not live in igloos and are snowbound 11 months of the year. We even swim in the fjord regions.

If you don't believe me, here is a picture of my bedroom



Hey Grothar, I heard we may be getting some 20s around here.
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Since I lived in both Greenland, Norway,(as well as a few other places, it may surprise some to know that coastal Norway has a surprisingly mild climate. While the interior sections, especially in the North has very cold and snowy climates, that is not the case on the coast. We do not live in igloos and are snowbound 11 months of the year. We even swim in the fjord regions.

If you don't believe me, here is a picture of my bedroom

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Quoting Ossqss:


Speaking of Norway, they have had quite the amazing November.

Can you translate this for us :)

http://www.yr.no/english/1.7405789




Hey, I get paid to do this. This is a short version

Norway had over a hundred new records in November.
This November in Norway is the within ones memory, only comparable to November 1919.

Shows a photo of Mette BrandsgårdØstlandet which has experienced thus far in November, even colder than in 1919.
The same applies to Trøndelag. This November, together with 1945 is the second driest year since 1900. This year 's November surpasses 1919, and thereby we can ascertain that we have experienced this month alone anything that matches since weather forecasting began over a hundred years ago.
Olav Hygen and the staff at the Norwegian Meteorological Institute said its climate division may not remember when they last saw an equally list of records.

It has been a very special november.

In addition to the fact that we, since the 1919 record, we are 3.9 degrees colder than normal, What it further shows is that Norway also has received 93 new coldest records of which to claim. In total, we have something over 200 weather stations in the country.
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Quoting DocBen:
"I see no satisfaction in being right if it has absolutely no impact, especially in an "I told you so" situation."


Valid point. I guess it can assuage the guilt I feel for the actions of my generation.


I wasn't trying to be argumentative, just making a point. I know that I don't live my life the way I should, with limited fossil fuel usage, "greener" forms of energy, and exerting more effort to recycle. So I don't have any room to talk. But, I would like to point out that regardless of if the warming is man-made or not, what's the harm in recycling? Keeping the earth cleaner? etc
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Quoting FtMyersgal:

So, that is what is meant by "busting out at the seams" LOL



Yes. Their neighbors must be so happy to have them around.
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Quoting islander101010:
seems to be some odd weather going on worldwide

Yep. Just as the theory predicts...
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Quoting atmoaggie:
So all time records of highs and lows are about as useful as surface temps on roads, when they may be repaved, moved, etc., by man...It is simply interesting, but has little meaning outside of local land use anthropogenic modification and consequences.

Oh, boy. Denial is such a funny, funny thing, isn't it? Faced with overwhelming evidence of a climate shift, the default contrarian position is to claim the evidence is wrong--and when that tack fails, they fall back to position #2: the evidence doesn't exist at all. (Position #3 says the evidence doesn't cover enough time; #4 says the evidence, even if it does exist, doesn't matter. And so on...)

When a particular scientific theory is offered, and when nearly every piece of credible observational data supports that theory, and when virtually no data supports any other theory, it's only the fool who refuses to see the truth.
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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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