Global warming and the frequency of intense Atlantic hurricanes: model results

By: Dr. Jeff Masters , 1:37 PM GMT en Abril 05, 2010

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Could global warming increase wind shear over the Atlantic, potentially leading to a decrease in the frequency of Atlantic hurricanes? There is a growing consensus among hurricane scientists that this is indeed quite possible. Two recent studies, by Zhao et al. (2009), "Simulations of Global Hurricane Climatology, Interannual Variability, and Response to Global Warming Using a 50-km Resolution GCM", and by Knutson et al. (2008), "Simulated reduction in Atlantic hurricane frequency under twenty-first-century warming conditions", found that global warming might increase wind shear over the Atlantic by the end of the century, resulting in a decrease in the number of Atlantic hurricanes. For example, the second study took 18 relatively coarse (>60 km grid size) models used to formulate the 2007 IPCC climate report, and "downscaled" them using a higher-resolution (18 km grid size) model called ZETAC that was able to successfully simulate the frequencies of hurricanes over the past 50 years. When the 18 km ZETAC model was driven using the climate conditions we expect in 2100, as output by the 18 IPCC models, the authors found that a reduction of Atlantic tropical storms by 27% and hurricanes by 18% by the end of the century resulted. An important reason that their model predicted a decrease in the frequency of Atlantic hurricanes was due to a predicted increase in wind shear. As I explain in my wind shear tutorial, a large change of wind speed with height over a hurricane creates a shearing force that tends to tear the storm apart. The amount of wind shear is critical in determining whether a hurricane can form or survive.


Figure 1. Top: predicted change by 2100 in wind shear (in meters per second per degree C of warming--multiply by two to get mph) as predicted by summing the predictions of 18 climate models. Bottom: The number of models that predict the effect shown in the top image. The dots show the locations where tropical storms formed between 1981-2005. The box indicates a region of frequent hurricane formation where wind shear is not predicted to change much. Image credit: Geophysical Research Letters, "Increased Tropical Atlantic Wind Shear in Model Projections of Global Warming", by Vecchi and Soden, 2007.

Since the Knutson et al. study using the 18 km resolution ZETAC model was not detailed enough to look at what might happen to major Category 3 and stronger hurricanes, a new study using a higher resolution model was needed. This was done by a team of modelers led by Dr. Morris Bender of NOAA's GFDL laboratory, who published their results in Science in February. The authors used the GFDL hurricane model--the model that has been our best-performing operation hurricane track forecasting model over the past five years--to perform their study. The GFDL hurricane model runs at a resolution of 9 km, which is detailed enough to make accurate simulations of major hurricanes. The researchers did a double downscaling study, where they first took the forecast atmospheric and oceanic conditions at generated by the coarse (>60 km grid) IPCC models, used these data to initialize the finer resolution 18 km ZETAC model, then used the output from the ZETAC model to initialize the high-resolution GFDL hurricane model. The final results of this "double downscaling" study suggest that although the total number of hurricanes is expected to decrease by the end of the century, we should expect an increase of 81% in the number of Category 4 and 5 storms in the Atlantic. This trend should not be clearly detectable until about 60 years from now, given a scenario in which CO2 doubles by 2100. The authors say that their model predicts that there should already have been a 20% increase in the number of Category 4 and 5 storms since the 1940s, given the approximate 0.5°C warming of the tropical Atlantic during that period. This trend is too small to be detectable, given the high natural variability and the difficulty we've had accurately measuring the exact strength of intense hurricanes before the 1980s.The region of the Atlantic expected to see the greatest increase in Category 4 and 5 storms by the year 2100 is over the Bahama Islands (Figure 2), since wind shear is not expected to increase in this region, and sea surface temperatures and atmospheric instability are expected to increase there.

The net effect of a decrease in total number of hurricanes but an increase in the strongest hurricanes should cause an increase in U.S. hurricane damages of about 30% by the end of the century, the authors compute, assuming that hurricane damages behave as they did during the past century. Over the past century, Category 4 and 5 hurricanes made up only 6% of all U.S. landfalls, but accounted for 48% of all U.S. damage (if normalized to account for increases in U.S. population and wealth, Pielke et al., 2008.)


Figure 2. Expected change in Atlantic Category 4 and 5 hurricanes per decade expected by the year 2100, according to the Science paper by Bender et al. (2010).

Commentary
These results seem reasonable, since the models in question have been successfully been able to simulate the behavior of hurricanes over the past 50 years. However, the uncertainties are high and lot more research needs to be done before we can be confident of the results. Not all of the IPCC models predict an increase in wind shear over the tropical Atlantic by 2100, so the increase in Category 4 and 5 hurricanes could be much greater. Also, the GFDL model was observed to under-predict the strength of intense hurricanes in the current climate, so it may not be creating enough Category 4 and 5 hurricanes in the future climate of 2100. On the other hand, IPCC models such as the UKMO-HadCM3 predict a very large increase in wind shear, leading to a drastic reduction in all hurricanes in the Atlantic by 2100, including Category 4 and 5 storms. So Category 4 and 5 hurricane frequency could easily be much greater or much less than the 81% increase by 2100 found by Bender et al.

The estimates of a 30% increase in hurricane damages by 2100 may be considerably too low, since this estimate assumes that sea level rise will continue at the same pace as was observed in the 20th century. Sea level rise has accelerated since the 1990s, and it is likely that this century we will see much more than than the 7 inches of global sea level rise that was observed last century. Higher sea level rise rates will sharply increase the damages due to storm surge, which account for a large amount of the damage from intense Category 4 and 5 hurricanes.

Keep in mind that while a 30% in hurricane damage by the end of the century is significant, this will not be the main reason hurricane damages will increase this century. Hurricane damages are currently doubling every ten years, according to Pielke et al., 2008. This is primarily due to the increasing population along the coast and increased wealth of the population. The authors theorize that the Great Miami Hurricane of 1926, a Category 4 monster that made a direct hit on Miami Beach, would have caused about $150 billion in damage had it hit in 2005. By 2015, the authors expect the same hurricane would do $300 billion in damage. This number would increase to $600 billion by 2025 (though I think it is likely that the recent recession may delay this damage total a few years into the future.) It is essential that we limit coastal development in vulnerable coastal areas, particularly along barrier islands, to reduce some of the astronomical price tags hurricanes are going to be causing. Adoption and enforcement of strict building standards is also a must.

The authors of the GFDL hurricane model study have put together a nice web page with links to the paper and some detailed non-technical explanations of the paper.

References
Bender et al., 2010, "Modeled Impact of Anthropogenic Warming on the Frequency of Intense Atlantic Hurricanes", Science, 22 January 2010: Vol. 327. no. 5964, pp. 454 - 458 DOI: 10.1126/science.1180568.

Vecchi, G.A., B.J. Soden, A.T. Wittenberg, I.M. Held, A. Leetmaa, and M.J. Harrison, 2006, "Weakening of tropical Pacific atmospheric circulation due to anthropogenic forcing", Nature, 441(7089), 73-76.

Vecchi, G.A., and B.J. Soden, 2007, "Increased Tropical Atlantic Wind Shear in Model Projections of Global Warming", Geophysical Research Letters, 34, L08702, doi:10.1029/2006GL028905, 2007.

Jeff Masters

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Quoting Jeff9641:


Yeah, Bastardi. I hope he's not right this year because if he is then Florida is some big trouble.

Jeff Mckown is my name not Edgar or Casey.
what? I thought it was jeffradamas. JK...really..jk.
Member Since: Septiembre 27, 2007 Posts: 1 Comments: 21416
One day the kids in Ms. Evans science class was disagreeing with her.
Ms. Evans was talking about evolution. Ms. Evans was and atheist so she didn't believe in God.
Then Johnny raised his hand and said, "But I thought God created mankind?"
Ms. Evans then replied, "Well can you see God?"
"No."
"Hear God?"
"No."
"Feel God?"
"No." This went on for quite a while.
"Well then God doesn't exist."
Then Johnny whispered back to his friend Jimmy, "Can you see Ms. Evan's brain. No, so that must not exist."
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Quoting Levi32:


And I agree with absolutely none of it, as everyone knows, but I was just trying to show that the AGW people think the Sahara will either shrink, get more moist, or move northward, which makes the Sahel more moist.
I knew where you were going with the info. I post sometimes and I don,t get the words out the way I want them. it su.x
Member Since: Septiembre 27, 2007 Posts: 1 Comments: 21416
Quoting hydrus:
I comprehend what your posts Levi. It is what Lovelock wrote that seems over the top with his assumptions on rapid changes in the earths climate.


And I agree with absolutely none of it, as everyone knows, but I was just trying to show that the AGW people think the Sahara will either shrink, get more moist, or move northward, which makes the Sahel more moist.
Member Since: Noviembre 24, 2005 Posts: 635 Comments: 26654
Quoting Levi32:


Drak, I'd really rather not be on your bad side. This is what happens when people who get along and agree on the tropics disagree on global warming theory.

If you look at the bottom half of the image which shows the summer precipitation, during the hurricane season, you can see that most of the Sahel that matters during the hurricane season, which is north of 10N, is moist on the model. Yes the NW corner is a bit drier, but most is not when you consider the Sahel as a whole. The moist areas would outweigh the dry spot and decrease overall dust carried into the Atlantic by the AEJ. Dr. Masters said as much himself.



You can also see the dry anomalies extending well into Europe, suggesting that the Sahara Desert may be moving slowly northward on the model

I'm sorry if illustrating my point so strongly by saying "rainforest" tipped you all off. My point was that the IPCC does expect the the Sahara Desert to either retreat northward or shrink with time, resulting in a moister Sahel. The whole point was dealing with their humidity forecast for the eastern Atlantic. No their official forecast does not say it will become a rainforest but it does suggest it may be on its way. Now let's please quit nit-picking on this issue.
I comprehend what your posts are saying Levi. It is what Lovelock wrote that seems over the top with his assumptions on rapid changes in the earths climate.
Member Since: Septiembre 27, 2007 Posts: 1 Comments: 21416
Quoting Jeff9641:


Wrong video!!LOL!!Maybe you meant to post this video. This is for 2009!


Edgar (Jeff9641) Casey...Are you talking about the Bastari video? I went by the title. Early 2009 Hurricane Predictions. I believe he did update it and was pretty much on point.
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Quoting hydrus:
I apologize. I should of remembered you were at college. You have a lot going on and the loss of a friend to cope with too.


Nice to be back though. I'll be fine.
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Quoting GeoffreyWPB:
Drak and Levi...without jumping into our time-travelling DeLorean 100 years into the future...you both do agree that, as of what you see now, this Hurricane season will be above average and the potential of more U.S. strikes is likely?


I believe we do.
Member Since: Noviembre 24, 2005 Posts: 635 Comments: 26654
GOM 120 Hour Surface Current Forecast Model
Member Since: Julio 3, 2005 Posts: 426 Comments: 128654
Quoting cchsweatherman:


Been dealing with several things in my life including a six class schedule in college, a new job, a new relationship, and the loss of a close personal friend. I'll try and be on here more often now that the semester is winding down here.
I apologize. I should of remembered you were at college. You have a lot going on and the loss of a friend to cope with too.
Member Since: Septiembre 27, 2007 Posts: 1 Comments: 21416
Quoting Drakoen:


(I thought you were out?)

You were exaggerating and "grasping for straws" because you couldn't refute my claims adequately. Again, the IPCC graphic shows a decrease in the precip over the northwest Sahel which wouldn't not allow for the dramatic moistening you want to claim. Again pot calling the kettle black when you refer to us playing with words. We took your same words and you failed to provide concrete evidence. You are certainly wrong in my view and you interpretations that could not even consider objectivity.


Drak, I'd really rather not be on your bad side. This is what happens when people who get along and agree on the tropics disagree on global warming theory.

If you look at the bottom half of the image which shows the summer precipitation, during the hurricane season, you can see that most of the Sahel that matters during the hurricane season, which is north of 10N, is moist on the model. Yes the NW corner is a bit drier, but most is not when you consider the Sahel as a whole. The moist areas would outweigh the dry spot and decrease overall dust carried into the Atlantic by the AEJ. Dr. Masters said as much himself.



You can also see the dry anomalies extending well into Europe, suggesting that the Sahara Desert may be moving slowly northward on the model

I'm sorry if illustrating my point so strongly by saying "rainforest" tipped you all off. My point was that the IPCC does expect the the Sahara Desert to either retreat northward or shrink with time, resulting in a moister Sahel. The whole point was dealing with their humidity forecast for the eastern Atlantic. No their official forecast does not say it will become a rainforest but it does suggest it may be on its way. Now let's please quit nit-picking on this issue.
Member Since: Noviembre 24, 2005 Posts: 635 Comments: 26654
Quoting GeoffreyWPB:
Drak and Levi...without jumping into our time-travelling DeLorean 100 years into the future...you both do agree that, as of what you see now, this Hurricane season will be above average and the potential of more U.S. strikes is likely?


I would have to agree that this will be an above average season with a greater threat on the United States.
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In looking forward to the upcoming Atlantic Hurricane Season, I'm really becoming more and more concerned as all the major signs point towards a very active season. Right now, the two most ominous developments are continually increasing TCHP (Tropical Cyclone Heat Potential) in the Caribbean and MDR as shown below and the continued decline of El Nino towards neutral conditions that appears destined for May. As Levi shed light on earlier, with a neutral to La Nina condition, storms tend to be more frequent across the Atlantic and tend to track more westward, posing a greater threat to land. That, in combination with very warm SSTs across the Atlantic and conducive TCHP in the Caribbean, could spell trouble for the upcoming season. Of course, the most important factor will be where these storms form and the steering currents at the time.


Figure 1 - Atlantic TCHP (Source: NOAA AOML)
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Drak and Levi...without jumping into our time-travelling DeLorean 100 years into the future...you both do agree that, as of what you see now, this Hurricane season will be above average and the potential of more U.S. strikes is likely?
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I think now would be a good time for a group Hug.

((((((((((WUBA's)))))))))

Recent GOES SST Weekly Composite Imagery Links
GOES SST/SSH images for 4/6/2010






Member Since: Julio 3, 2005 Posts: 426 Comments: 128654
Quoting Levi32:
Just google it guys lol. It's all over the place. You guys now think everything I was trying to say has no merit because I stated the worst-case scenario prediction. I didn't say that would happen in 90 years, and I didn't say the IPCC thought that it would. I said they thought it may start to, and could eventually become more of a forest than a desert.

But you guys love to play with words and mess up what anyone tries to post against your ideas. I haven't seen any hard evidence from your side. Al Gore says the Sahara is growing, maybe you should cite him. Oh I forgot, he's not a scientist. The IPCC says the Sahel will moisten and the Sahara Desert will shift northward or shrink or both. You decide....it's your data and your predictions that you believe in, not mine. I'm only posting what you guys post all the time.

And don't get on me for these links being mostly news sites or things like National Geographic. I'm not a fan of posting such stuff, but you post those all the time too. You can pretend all the people writing them are lying about their sources if you want.

Sahara Desert Greening Due to Climate Change?

"Africa's deserts are in retreat," according to New Scientist magazine

Global warming could end Sahara droughts, says study

Occupying some 3.5m square miles of northern Africa, the Sahara desert is expected to shrink with global warming


(I thought you were out?)

You were exaggerating and "grasping for straws" because you couldn't refute my claims adequately. Again, the IPCC graphic shows a decrease in the precip over the northwest Sahel which wouldn't not allow for the dramatic moistening you want to claim. Again pot calling the kettle black when you refer to us playing with words. We took your same words and you failed to provide concrete evidence. You are certainly wrong in my view and your interpretations that could not even consider objectivity.
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Modeled Impact of Anthropogenic Warming on the Frequency of Intense Atlantic Hurricanes




Isn't it conventional wisdom that hurricanes will get stronger in a warmer climate?


There are several lines of evidence, primarily based on theories for the maximum intensity that hurricanes can attain, and on numerical models of storm development in idealized conditions as summarized in this figure, that suggest that this "potential intensity" will increase on average as the climate warms.

However, these studies only consider the theoretical upper limit on the intensity of hurricanes, and do not address the important question of how many hurricanes will approach this upper limit. Previous modeling studies that have examined how the frequency of tropical cyclones might change could not simulate (or have not documented their ability to simulate) the intense systems that historically have caused most of the hurricane damage in the U.S.

The relationship between temperature and storm intensity is not as simple as "warmer oceans => stronger storms" since there are a variety of mechanisms that are capable of limiting the numbers of very intense storms. An example is increases in wind shears which can prevent strengthening that might otherwise occur under favorable conditions for storm development. As part of the goal of directly simulating the atmosphere in computer models at GFDL, this paper describes what we believe to be a credible direct dynamical simulation of the effects of climate change on the frequency of intense hurricanes.
Member Since: Julio 3, 2005 Posts: 426 Comments: 128654
777

You are like a chameleon, fascinating.
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Thank you amd.
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Answers to Frequently Asked Questions About this Study:



You say that the trend in intense hurricanes will not be detectable until the latter part of the century, but hasn’t there already been an increase in the number of intense tropical storms?


A large increase in the number of category 4 and 5 hurricanes has been observed in the Atlantic since 1980. But we expect the signal forced by greenhouse gases to be a long-term trend, and this period is too short to be able to distinguish a long-term trend from the multi-decadal fluctuations that are known to exist in the Atlantic. If we push back further in time, to minimize the contribution from internal variability, the raw data still indicates an increasing trend (for example, the observed trend since the 1940's in category 4 and 5 hurricanes suggests a doubling over this time period). However, we believe that the reliability of the basin-wide category 4 and 5 counts decreases as one goes back in time, particularly prior to the satellite era. Our view is that potential data problems need to be addressed before one can have much confidence in quantitative trends on time scales long enough to isolate the greenhouse-gas induced trend. In the absence of the clear detection of a trend, we cannot use the observations of recent decades to either confirm or refute the trends projected by our model.
Member Since: Julio 3, 2005 Posts: 426 Comments: 128654
Quoting aquak9:
I didn't see any tsunami warnings, but I probably don't know where to look.


The tsunami watches that were in place immediately following the event have been cancelled.
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Quoting cchsweatherman:


Been dealing with several things in my life including a six class schedule in college, a new job, a new relationship, and the loss of a close personal friend. I'll try and be on here more often now that the semester is winding down here.


sorry about your loss bro, I look forward to seeing more of you.
Member Since: Septiembre 23, 2006 Posts: 1 Comments: 2563
Quoting homelesswanderer:


This is the scariest thing I've ever read in connection to hurricanes. The worst has already happened once. I went through Humberto but wow!

A more intense example of rapid intensification occurred in Central America in 2007, when a tropical depression (with winds of no more than 38 mph) rapidly intensified into the Category 5 Hurricane Felix with 175 mph winds within two days. The storm was over open water at the time of its initial intensification, but after weakening, it quickly re-intensified back into a Category 5 storm just before moving inland, killing dozens and causing severe damage in Honduras and Nicaragua.


It went through an eyewall replacement cycle
Member Since: Septiembre 23, 2006 Posts: 1 Comments: 2563
Quoting hydrus:
Where ya been? You always pop outta da blue.


Been dealing with several things in my life including a six class schedule in college, a new job, a new relationship, and the loss of a close personal friend. I'll try and be on here more often now that the semester is winding down here.
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778. amd
Quoting Kibkaos:
Hey guys I hope everyone is doing well I am writing because I was curious about the current El Nino. Is there a drastic change in the conditions or will there be any change. I am here in SE TX near the Gulf. Looking forward to reading your responses.


El Nino is slowly weakening at the moment. Currently, the el nino is still moderate, but barely. In terms of water temperatures, el nino will probably be gone by the end of may, and water temperatures in the pacific will probably be completely neutral or even below normal by sometime in June.

Therefore, by the heart of the Atlantic hurricane season, conditions should be favorable to very favorable for more tropical development in the Atlantic compared to normal, and there will be more development than last year. JMHO.

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Quoting bappit:
Didn't sound like hyperbole to me. When I said it was a gross distortion he told me to prove it.


And you still haven't. Show me where they say it will get drier and more desert-like instead of wetter and more forest-like.
Member Since: Noviembre 24, 2005 Posts: 635 Comments: 26654
Quoting GeoffreyWPB:
Hurricane Intensity Still Stymies Forecasters


This is the scariest thing I've ever read in connection to hurricanes. The worst has already happened once. I went through Humberto but wow!

A more intense example of rapid intensification occurred in Central America in 2007, when a tropical depression (with winds of no more than 38 mph) rapidly intensified into the Category 5 Hurricane Felix with 175 mph winds within two days. The storm was over open water at the time of its initial intensification, but after weakening, it quickly re-intensified back into a Category 5 storm just before moving inland, killing dozens and causing severe damage in Honduras and Nicaragua.
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I didn't see any tsunami warnings, but I probably don't know where to look.
Member Since: Agosto 13, 2005 Posts: 166 Comments: 26054
Quoting cchsweatherman:
Where ya been? You always pop outta da blue.
Member Since: Septiembre 27, 2007 Posts: 1 Comments: 21416
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geeez another 7.7 offa the coast of Sumatra?

"She's breaking up, Captain!"
Member Since: Agosto 13, 2005 Posts: 166 Comments: 26054
Didn't sound like hyperbole to me. When I said it was a gross distortion he told me to prove it.
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Quoting Patrap:


Joe Bastardi Agrees with that usually round the June 3rd date every year,or the first Invest off of Africa


And you'd know that how? You don't watch his videos or read his blog do you.
Member Since: Noviembre 24, 2005 Posts: 635 Comments: 26654
Half time score, old guys 2, young guys 14...each forcing the other to prove their point with intuition and not just copy/pasting someone elses opinion. That's what makes this blog what it is...
Member Since: Febrero 11, 2010 Posts: 0 Comments: 840
Just google it guys lol. It's all over the place. You guys now think everything I was trying to say has no merit because I stated the worst-case scenario prediction. I didn't say that would happen in 90 years, and I didn't say the IPCC thought that it would. I said they thought it may start to, and could eventually become more of a forest than a desert.

But you guys love to play with words and mess up what anyone tries to post against your ideas. I haven't seen any hard evidence from your side. Al Gore says the Sahara is growing, maybe you should cite him. Oh I forgot, he's not a scientist. The IPCC says the Sahel will moisten and the Sahara Desert will shift northward or shrink or both. You decide....it's your data and your predictions that you believe in, not mine. I'm only posting what you guys post all the time.

And don't get on me for these links being mostly news sites or things like National Geographic. I'm not a fan of posting such stuff, but you post those all the time too. You can pretend all the people writing them are lying about their sources if you want.

Sahara Desert Greening Due to Climate Change?

"Africa's deserts are in retreat," according to New Scientist magazine

Global warming could end Sahara droughts, says study

Occupying some 3.5m square miles of northern Africa, the Sahara desert is expected to shrink with global warming
Member Since: Noviembre 24, 2005 Posts: 635 Comments: 26654
Don't write it off yet this storm has a while to go and technically it would only be tropical cyclone free
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99W having some problems. Look like the world will be cyclone-free pretty soon. Seems rare when that happens.
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Hey guys I hope everyone is doing well I am writing because I was curious about the current El Nino. Is there a drastic change in the conditions or will there be any change. I am here in SE TX near the Gulf. Looking forward to reading your responses.
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Quoting winter123:


Whoever wrote that is a great doomcaster. He should come to JM's blog.

Lemme try... The first hurricane of 2010 is forecasted to form in the carribean in two weeks. It will intensify to a cat 5, then hit New Orleans, turn back into the GOM then hit Miami, then reintensify to a cat 9 and hit NYC.


Joe Bastardi Agrees with that usually round the June 3rd date every year,or the first Invest off of Africa
Member Since: Julio 3, 2005 Posts: 426 Comments: 128654
Quoting FloridaTigers:


What does this mean?


That El Nino continues to fade.
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Quoting Tropicsweatherpr:
The 30 day SOI index continues to go up and is close to going positive.



What does this mean?
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Quoting Levi32:


Actually the Sahara 10,000 years ago was quite dry, like the American Southwest. Of course 5 to 10 inches of rain a year is a lot more than none, and there were rivers, and lakes like the Great Salt Lake in the Sahara.

But to call the Sahara a green forested wonderland is just false. Didn't happen.


You're saying Dr. Masters was wrong in saying this:

Could increased rainfall lead to a re-greening of the Sahara towards the lush conditions that existed 12,000 years ago?

Anyway, if you guys are going to get this petty, I'll just leave. I've given hard evidence.

First you guys thought I was wrong that El Nino doesn't increase shear significantly over the eastern MDR. I showed the historical data. Then you said I was wrong that the IPCC predicted a wetter greener Africa, again I posted evidence, from your very own Dr. Masters.

What else do you guys want? You're picking at every tiny little thing you can find right now. I gave you what you wanted, but no matter what I say it will never be good enough and I know that, so I'll bow out now.


I never said that so don't include me into that bunch.
And the second thing is, you exaggerated the IPCC climate forecast which can easily be loosely interpreted; however, in my view does not prove your argument as to the increase in humidity levels over the observation area with the highest deficiency and you did not address my statements about conditions off the southeast coast.

Jeff Masters, took out something that another scientist said which you took up as being the representative for the whole IPCC.
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The 30 day SOI index continues to go up and is close to pass the line to positive.

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This Lovelock guy sounds like those "doomcasters" who come ringing every year when one model 240 hours out predicts a Cat 4 NYC hit.
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It is a free country and people are allowed to believe what they want. I believe that the world population will not be ( culled ) from 6.8 billion to 500 million by 2100. Instead it will increase substantially and exponentially. There will be changes in the Earths climate, but not at the speed stated by Lovelock. It is just what I believe, I could be wrong.
Member Since: Septiembre 27, 2007 Posts: 1 Comments: 21416
Quoting Levi32:


The rainforest is an extreme scenario that I have seen time and again proposed unofficially that could happen during the next 500 years. You're not going to see that in an official prediction or scientific paper because they won't go beyond this century yet.

My point was about their 700mb humidity prediction, and their forecast for more precipitation supports what I said, as it decreases dust and increases moisture over the eastern Atlantic which is why the IPCC forecast is different there than our historical records of El Ninos.

Perhaps I should refrain from using hyperboles. For people that use them all the time when talking about AGW, I'm surprised you guys can't handle them.


You used a false hyperbole as a rebuttal to my observation that juxtaposed the IPCC and the El Nino years.
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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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