Extreme Drought to Flood in Georgia: Weather Whiplash Strikes Again

By: Dr. Jeff Masters , 3:57 PM GMT on May 06, 2013

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The remarkable storm that brought record-breaking May snows and cold to the Midwest last week continues to spin over the Southeast U.S. The storm is unleashing flooding rains, bringing a case of "Weather Whiplash" to Georgia: flooding where extreme drought had existed just a few months ago. The storm formed when a loop in the jet stream of extreme amplitude got cut off from the main flow of the jet over the weekend, forming a "cutoff low" that is now slowly spinning down as it drifts east over the Southeast U.S. On Sunday, the storm dumped 3.4" of rain on Atlanta, Georgia--that city's sixth heaviest May calendar day rain storm since record keeping began in 1878. Remarkably, the rains were also able to bring rivers in Central Georgia above flood stage. This portion of the country was in "exceptional drought"--the worst category of drought--at the beginning of 2013.


Figure 1. The record May snowstorm that hit the Midwest U.S. on May 1 - 3, 2013, got cut off from the jet stream and was seen spinning over the Southeast U.S. on Sunday, May 5, in this image from NASA's MODIS instrument. The 3.4" of rain that fell on Atlanta, Georgia on May 5 was that city's sixth heaviest May calendar day rainfall since record keeping began in 1878.

Weather Whiplash
Weather Whiplash--a term originally coined by science writer Andrew Freedman of climatecentral.org to describe extreme shifts between cold and hot weather--is also a excellent phrase we can use to describe some of the rapid transitions between extreme drought and floods seen in recent years. I brought up a remarkable example in mid-April, when a 200-mile stretch of the Mississippi River north of St. Louis reached damaging major flood levels less than four months after near-record low water levels restricted barge traffic, forcing the Army Corp to blast out rocks from the river bottom to enable navigation. As the climate warms, the new normal in coming decades is going to be more and more extreme "Weather Whiplash" drought-flood cycles like we have seen in the Midwest and in Georgia this year. A warmer atmosphere is capable of bringing heavier downpours, since warmer air can hold more water vapor. But you still need a low pressure system to come along and wring that moisture out of the air to get rain. When natural fluctuations in jet stream patterns take storms away from a region, creating a drought, the extra water vapor in the air won't do you any good. There will be no mechanism to lift the moisture, condense it, and generate drought-busting rains. The drought that ensues will be more intense, since temperatures will be hotter and the soil will dry out more.


Figure 2. Weather Whiplash in Georgia, 2013: the center of the state was in exceptional drought as the beginning of the year, but heavy rains in February, March, and April busted the drought. Heavy May rains have now brought flooding. Image credit: U.S. Drought Monitor.

Weather Whiplash in the Southeast U.S. more likely due to an intensification of the Bermuda High
This year's "Weather Whiplash" in Georgia is the second time in the past decade the state has gone from exceptional drought to flood. In September 2007, Atlanta, Georgia was in the midst of a 1-in-100 year drought, and was just weeks away from running out of water. Yet just two years later, the drought had been busted, and a phenomenal 1-in-500 year flood ripped through the city, killing ten and causing $500 million in damage. According to a 2011 study by a Duke University-led team of climate scientists, "Changes to the North Atlantic Subtropical High and Its Role in the Intensification of Summer Rainfall Variability in the Southeastern United States", the frequency of abnormally wet or dry summer weather in the southeastern United States has more than doubled in recent decades, due to an intensification of the Bermuda High. The scientists found that the Bermuda High, which is centered several hundred miles to the east of the Southeast U.S., has grown more intense during summer and has expanded westwards over the past 30 years. Since high pressure systems are areas of sinking air that discourage precipitation, this has made abnormally dry summers more common over the Southeast U.S. However, in summers when the Bermuda High happens to shift to the east, so that high pressure is not over the Southeast U.S., the stronger winds blowing clockwise around the Bermuda High bring an increased flow of very moist subtropical air from the south to the Southeast U.S., increasing the incidence of abnormally wet summers. Thus, the intensification of the Bermuda High has made extreme droughts and extreme floods more likely over the Southeast U.S. Using climate models, the scientists determined that human-caused global warming was likely the main cause of the significant intensification in the Bermuda High. Thus "Weather Whiplash" between drought and flood will probably become increasingly common in the coming decades over the Southeast U.S.


Figure 3. Observed June-July-August departure of precipitation from average over the SE United States for a 60-yr period (mm day−1). Horizontal dashed lines represent 1 standard deviation of the summer rainfall. Note that summer precipitation extremes exceeding one standard deviation have more than doubled during the most recent 30-year period compared to the previous 30-year period. Image credit: Li et al., 2011, Journal of Climate.

New climate change blog at The Guardian
In these days of steadily decreasing media coverage of climate change (and all science, in general), its good to see a fresh new source of good science appear in a major newspaper. The Guardian, a prominent UK news source, has a new blog called Climate Consensus – The 97%. The primary authors are Dana Nuccitelli of SkepticalScience and John Abraham, Associate Professor at the University of St. Thomas in Minnesota. The first post at the new blog is titled “Why is Reuters puzzled by global warming’s acceleration?”

Related Links
Don't miss the summary post on last week's remarkable snow storm by wunderground's weather historian, Christopher C. Burt, The Phenomenal May Snowstorm of May 1-3, 2013

Extreme Drought to Extreme Flood: Weather Whiplash Hits the Midwest: my April 19, 2013 blog post.

Southeast U.S. drought: another Tropical Storm Alberto needed: my April 2012 post describing how 20% - 50% of all droughts in the Southeast U.S. are broken by tropical storms or hurricanes.

Study: Global warming is driving increased frequency of extreme wet or dry summer weather in southeast, so droughts and deluges are likely to get worse: October 2010 post by Joe Romm at climateprogress.org.

Jeff Masters

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Second the Ad Block. Also throw in Click-to-Flash. I've kept a 10-year old computer running smoothly by blocking 90% of the crap most web sites attempt to load on one's computer.
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tied for 10th all time

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Quoting LargoFl:
I wonder what would happen if we ALL..stopped posting here for a month?..do you think the ads would vanish?

Hello all

No, they are targeted ads. If I view this website via IE or Safari I get ads for Australia/Sydney, yet this is an USA based website. It's sorta like the "ads" on facebook which are also targeted.
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Quoting ChillinInTheKeys:


Or, since the Doctor was nice enough to create and operate this forum, you could just kick in the $10.00.

I'm a paying member, but I still have Adblocker. No more ads on my browser.
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Quoting ChillinInTheKeys:


Or, since the Doctor was nice enough to create and operate this forum, you could just kick in the $10.00.


That's what I did, but I'm sure Adblock works for WU plus you don't have to deal with Ads again.
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Quoting CybrTeddy:


Adblock Plus. Free, simple, no more ads.


Or, since the Doctor was nice enough to create and operate this forum, you could just kick in the $10.00.
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510. beell
Quoting StormTrackerScott:
The ads on this blog should be weather related. Just my opinion.


Maybe clear your cookie cache before entering this blog.
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Quoting StormTrackerScott:
The ads on this blog should be weather related. Just my opinion.


Adblock Plus. Free, simple, no more ads.
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Quoting StormTrackerScott:


Yeah, at times Doc has had sexually explicit ads which are very virus prone. Makes no sense that Doc merged with TWC and yet his ads have gotten more raunchy especially sense so many kids visit this site. I think Doc needs to look deeper into his ads especially when I log on here and see girls with their chest hanging out asking if I want a date. I come on this site at night and my wife is like what is that and I have to explain that it's a weather blog but the editor has ads that aren't meant for this blog.


Sure :)
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Quoting JohnLonergan:



But even more important than Occam's razor is "It must comply with basic physics". There is no physical basis to attribute increased heat content of the earth to solar trends, Milankovitch cycles, ENSO, PDO, AMO or IPU.


Yes, very true. The simplest explanation still has to abide by the laws of the universe. If it doesn't, it's still... wrong. Thus, the best explanation for any question in science is likely to be a simple one that does not violate anything we already know to be correct.
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Quoting goosegirl1:
Quoting Snowlover 123: **It seems to me that you aren't even willing to consider the possibility of a more significant solar influence on the 20th Century Global Warming.**

Call me crazy, but I don't see that happening. I didn't see anyone refuting that solar activity effects climate on Earth- this is well known, if sometimes poorly understood. What is happening, is that some are saying this could be the main driving force for climate change. This has been shown as incorrect.

When doing scientific research, always make good use of Occam's razor. If we have shown that solar activity has not caused 20th century warming, research another hypothesis.



But even more important than Occam's razor is "It must comply with basic physics". There is no physical basis to attribute increased heat content of the earth to solar trends, Milankovitch cycles, ENSO, PDO, AMO or IPU.
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once it gets 90f or over cen fl can produce its own showers
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A fantastically beautiful spring day for most the Great Lakes area!



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Quoting SouthernIllinois:

But the publish date? More information from current research lately has that in question?


I think you're just trying to get a rise out of me. Sorry, not biting, today.
Member Since: July 20, 2008 Posts: 0 Comments: 2450
Quoting Snowlover 123: **It seems to me that you aren't even willing to consider the possibility of a more significant solar influence on the 20th Century Global Warming.**

Call me crazy, but I don't see that happening. I didn't see anyone refuting that solar activity effects climate on Earth- this is well known, if sometimes poorly understood. What is happening, is that some are saying this could be the main driving force for climate change. This has been shown as incorrect.

When doing scientific research, always make good use of Occam's razor. If we have shown that solar activity has not caused 20th century warming, research another hypothesis.
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Quoting SouthernIllinois:

Why do you use that graph? Isn't it a bit outdated?


No, it shows sunspot activity from 1750 to 2012.
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I wonder what would happen if we ALL..stopped posting here for a month?..do you think the ads would vanish?
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Quoting SFLWeatherman:
I do not have ads!:)
..add my vote to that grrrr
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I do not have ads!:)
Quoting StormTrackerScott:
The ads on this blog should be weather related. Just my opinion.
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The ads on this blog should be weather related. Just my opinion.
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491. Irth
Quoting biff4ugo:
How do they know there is no ocean under the Saturn Hurricane? I haven't seen a map of the surface of Saturn. With it's increased gravity and atmospheric depth, when do dense liquid/gasses become an ocean there?


Saturn's makeup is very similar to that of our Sun, but on a much smaller scale. It's made up of 96% molecular hydrogen (H2), 3% Helium, with the remaining 1% being everything else from Ethane, Methane, Ammonia, Water, and a whole host of other organic compounds, silicates and metals.

Hydrogen becomes compressed to a liquid like state once it's squeezed to a density of roughly 0.01g/cubic cm. Saturns immense size and gravity allow this compression to happen almost all the way to the tops of the clouds we see (99.9% of the radius of Saturn). If there were an 'ocean', it would be an ocean of Hydrogen.

Also, deeper down, this same process is capable of compressing Helium into liquid droplets. These droplets 'rain' down through the hydrogen towards the core in a process call 'helium rain'. As these droplets fall, they produce friction, which in turn releases heat. This heat is the source of energy for the storm activity we see on Saturn.

The polar 'huricane' we observe now is explained by six nearly evenly spaced high-pressure zones around the pole. The hexagonal pattern exists inside and to the north of all six high pressure zones. The clockwise flow around these high pressure zones creates the counterclockwise flow within the polar vortex.
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Quoting StormTrackerScott:


Yeah, at times Doc has had sexually explicit ads which are very virus prone. Makes no sense that Doc merged with TWC and yet his ads have gotten more raunchy.


It is The Weather Channel after all
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Quoting SouthernIllinois:
There have been an extraordinary amounts of intense sunspot activity in the past decade, perhaps accounting for some of the recent warming on the globe from the late 1990's to 2012--a very warm year.


Really?

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Quoting PTXer:

One of the ads on the page is probably less than reputable. Just don't click on any of them.


Yeah, at times Doc has had sexually explicit ads which are very virus prone. Makes no sense that Doc merged with TWC and yet his ads have gotten more raunchy especially sense so many kids visit this site. I think Doc needs to look deeper into his ads especially when I log on here and see girls with their chest hanging out asking if I want a date. I come on this site at night and my wife is like what is that and I have to explain that it's a weather blog but the editor has ads that aren't meant for this blog.
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485. PTXer
Quoting FunnelVortex:
Guys, I keep getting a message that says:

"www.wunderground.com contains content from um.eqads.com, a site known to distribute malware. Your computer might catch a virus if you visit this site."

Could someone tell me what is going on!?

One of the ads on the page is probably less than reputable. Just don't click on any of them.
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Quoting GeorgiaStormz:


you moved to georgia?


that was a quick move from New York.
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Quoting pcola57:
Sorry..
I'm not getting that message Funnel..
Do you have a paid membership here?


No
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Quoting FunnelVortex:
Guys, I keep getting a message that says:

"www.wunderground.com contains content from um.eqads.com, a site known to distribute malware. Your computer might catch a virus if you visit this site."

Could someone tell me what is going on!?


Someone sent a virus to your computer.
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Sorry..
I'm not getting that message Funnel..
Do you have a paid membership here?
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Quoting trHUrrIXC5MMX:
So it has been raining here since Friday, with brief stops. Today is the 4th day and expecting more rain tonight and tomorrow morning
:(

Over 4" have been reported across the area here and for the last few days temps have been cooler than those in NYC.. what is this!?

Ever since I moved to Georgia there has been some weird weather going on.

darn upper low!


you moved to georgia?
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No tornado outbreaks thru the end of May. Pattern seems to be locked.

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Guys, I keep getting a message that says:

"www.wunderground.com contains content from um.eqads.com, a site known to distribute malware. Your computer might catch a virus if you visit this site."

Could someone tell me what is going on!?
Member Since: October 20, 2012 Posts: 7 Comments: 2866
FL is going to get good rain!:)

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Quoting ScottLincoln:

Wow. That was certainly... interesting. Did you catch in that paper how they brought in cosmic ray flux? On subsequent pages they basically suggested that during times of low solar activity (and thus, higher cosmic rays hitting earth), there would be more clouds and lower temperatures. Ignoring for a second the fact that the cosmic ray hypothesis is weak and has been heavily refuted (and the fact that temperature and cosmic ray intensity do not correlate), is it not interesting that its the sun causing the warming because solar activity is increasing, but it's also the sun causing the warming because solar activity is decreasing.


The Cosmic Ray Hypothesis has evidence on both sides of the spectrum. There are observed correlations between precipitation changes and Cosmic Rays. There are papers showing a link between the Diurnal Temperature Range and Cosmic Rays. There is evidence that aerosols correlate to Cosmic Rays during Forbush Decreases, and that tree rings correlate to Cosmic Rays. All of this supports the hypothesis that Clouds are influenced by Cosmic Rays. There are other papers which show that Cosmic Rays do not correlate with Cloud data from satellites. However, a lot of the cloud data is more uncertain than precipitation data. What is likely, is that there is some sort of an amplification mechanism, be it Cosmic Rays modulating Cloud Cover, or through some other process. What is an interesting observation made by several papers, is that the total forcing over the course of the solar cycle is somewhere between 1-2 w/m^2.



Using data from Sea Surface Temperatures, Sea Level Changes, and from Ocean Heat Content measurements, we can see that the indirect and direct solar forcing, the "amplifying" mechanism to the TSI variations, is very likely 1-2 w/m^2. The above picture is from Nir Shaviv, and uses data from Shaviv 2008.

Also, the Benestad paper is not completely uncontroversial as you made it out to be. Others have found a link between the length of the solar cycle and Hemispheric temperatures throughout the 20th Century.

http://onlinelibrary.wiley.com/doi/10.1029/2001JA 900027/abstract

It has previously been demonstrated that the mean land air temperature of the Northern Hemisphere could adequately be associated with a long-term variation of solar activity as given by the length of the approximately 11-year solar cycle. In this paper it is shown that the right cause-and-effect ordering, in the sense of Granger causality, is present between the smoothed solar cycle length and the cycle mean of Northern Hemisphere land air temperature for the twentieth century, at the 99% significance level. This indicates the existence of a physical mechanism linking solar activity to climate variations.

It should also be noted that while Dr. Benestad did not find a trend in the Sunspot Number, the Geomagnetic AA Index, probably the best index of Solar Activity, shows an increasing trend during the late-20th Century. We can see that right around 1960 is where the Sunspot Number and the Geomagnetic AA Index start to diverge, so thus, the Sunspot Number after 1960 is not a good proxy of soalr activity.



Source: Georgieva et al. 2012

Quoting ScottLincoln:


This one you really do not even have to read to clearly see the issue. You responded to a post about climatic warming. As in, a long term trend. The part you highlighted from the article is about comparing rainfall variability to solar variability. As in, not changes to the long term climate, changes to the noise. You need to re-educate yourself on the differences between climate variability and climate change


Perhaps you misread my earlier post.

From post 346, I had wrote,

There are a bunch of papers using observations from the sun and observations from regional, hemispheric, and global temperatures and precipitation that suggest otherwise. If I may name three:

A climate change isn't just measured in temperatures, as you know. It's measured in changes in precipitation as well. The study concluded that,

It can be concluded that solar variability seems to dominate the long-period
variation of summer precipitation
in these areas.


The "long period variations" refers to variations in precipitation on a long term scale; ie a climate variation on the centennial timeframe.

Quoting ScottLincoln:



I discussed this already above. Solar cycle length does not correlate with the warming. No reason to search for wavelengths and polynomial best fits, nor a ratio of pirates to global heat records. We already measure the total solar irradiance that is known to actually matter for climate, and it's stable, if not slightly cooling. We don't need a proxy to approximate solar irradiance if we can actually measure it, nor do we need to create some new timeseries, derived from the data we already have, in search for some correlation. We already have known physical mechanisms for what causes climate to change, and they are behaving as expected.


It seems to me that you aren't even willing to consider the possibility of a more significant solar influence on the 20th Century Global Warming. The paper found a link between solar cycle length and temperature changes in Jeddah, Saudi Arabia. Other papers have found a good link between solar parameters and temperatures.



The figure above is from a paper by Kishcha et al. 1999. The strong similarity between the solar activity variations and temperature indicates a solar link to temperatures over the 20th Century. The top panel represents Solar Cycle Length. The panel below shows a Composite Total Solar Irradiance Reconstruction from Hoyt and Schatten 1993 based off of five solar indicies. Hoyt and Schatten found that a large portion of the variance in temperature can be explained by Solar Activity. The panel below the Hoyt and Schatten 1993 reconstruction is the Northern Hemispheric Surface Temperatures. At the bottom, are sunspot numbers. Unfortunately, since Sunspot Numbers do not account for all solar activity, they are not particularly good solar activity proxies.



The figure above from Dorman 2012 shows a good link between Cosmic Rays and the late-20th Century Climate Change.

Quoting ScottLincoln:


Once you source this information with actual papers, then we can discuss. We don't use graphics from serial disinformation blog sites at face value in science.


All of the papers referred to in the image are sourced and are peer reviewed science.
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Got down to 57 in WPB for me!!!:)
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who is ready for the 17 year cicadas?


i dont think ga has any so...
Member Since: February 11, 2012 Posts: 0 Comments: 9475
A cross section of my state through my city. As you can see, the atmosphere is very stable today.



But we have this coming within the next 48 hours bringing a chance of rain.

Member Since: October 20, 2012 Posts: 7 Comments: 2866
Quoting GeorgiaStormz:
I think im gonna cry

widespread 10-20F below normal in eastern us
20-30 below normal in Ohio valley
30 below in west virginia.


Yeah the NWS has my highs only in the mid 50s for, at least, the first part of next week. To think it has been in the 70s and 80s the past week for me...
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I think im gonna cry

widespread 10-20F below normal in eastern us
20-30 below normal in Ohio valley
30 below in west virginia.

Member Since: February 11, 2012 Posts: 0 Comments: 9475
Quoting AtHomeInTX:
Hmmmmm...what have we here?



Extratropical Cyclones, thats what.
Member Since: October 20, 2012 Posts: 7 Comments: 2866
Love living in FL as we don't play!


Florida tries to speed up executions as Maryland, other states repeal death penalty

Read more: http://www.foxnews.com/politics/2013/05/06/florida -tries-to-speed-up-executions-as-maryland-other-st ates-repeal-death/?test=latestnews#ixzz2SbmIPLHK
Member Since: February 28, 2013 Posts: 2 Comments: 1044
Quoting Torito:


According to that chart, global warming has slowed in the past 2 years..


And the chart also shows a 30 year cooling period from the 40s to the 70s, despite increasing CO2 levels. This could have been due to natural variation, or 'global dimming' due to particulate and SO2 pollution, or a combination of both.

The simplistic notion that because warming has slowed over the past decade, despite increasing atmospheric CO2, is evidence that CO2 is not responsible for the warming, shows how poor the deniers' grasp of environmental science really is.
Member Since: July 20, 2008 Posts: 0 Comments: 2450
Quoting Snowlover123:
Not at all ridiculous. The pause now...[has been] captured well from HadCruT4:
You surely know that HadCRUT measures surface temperatures only. You also surely know that, as has been empirically shown (Levitus et al. [2012]), recent prolonged and recurring La Nina episodes have been forcing the vast majority of warming into the oceans. And you also surely know that the amount of heat being stored in the oceans right now is astounding, the energy equivalent of several Hiroshima-sized atomic bombs being detonated every second. In fact, there's so much heat that "...if this heat were somehow instantly transferred to the lower 10 km of the global atmosphere it would result in a volume mean warming of this atmospheric layer by approximately 36C (65F)."

warming

So people really need to stop with the "pause" bit. There's been no pause in warming. Absolutely none whatsoever. The planet is continuing to heat at a rapid rate because of the increasing concentrations of CO2 we're pumping into the atmosphere (more than 3.4 million tonnes per hour, every hour of every day of every year). So anytime someone says, "The planet hasn't warmed in X years," I simply toss them unceremoniously into the same bin as those low-information types who believe in a flat Earth or a young Earth.
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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.