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

By: Dr. Jeff Masters , 1:37 PM GMT on April 05, 2010

Share this Blog
7
+

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

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 955 - 905

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46Blog Index

Wow. Another 7.7 earthquake, 2nd in 3 days!
Member Since: October 25, 2005 Posts: 19 Comments: 20686
953. Skyepony (Mod)
Quoting AstroHurricane001:


Hmm, warm anomaly of the Gulf Stream from New England to between Bermuda and Newfoundland to west of Greenland. Could an extratropical remnant of a hurricane travel up that anomaly this season?


When I worked out my analog years for the up coming season, comparing the other 6 most similar ENSO years going back over the last 6 months.. most or all those years had at least 1 early season storm, between like A & D name that paralleled the coast well off shore up where that warm streak is coming together. Get some more heat from the gulf to connect it & it looks set for action. It's why I predicted at least 1 A-D storm to travel that path.
Member Since: Posts: Comments:
Quoting skepticall2:
From the dictionary:
skep·ti·cal   [skep-ti-kuhl] Show IPA
–adjective
1.
inclined to skepticism; having doubt: a skeptical young woman.
2.
showing doubt: a skeptical smile.
3.
denying or questioning the tenets of a religion: a skeptical approach to the nature of miracles.
4.
(initial capital letter) of or pertaining to Skeptics or Skepticism.


There are 2 L's at the end because the 1 L Skeptical was taken. Don't call me out please it doesn't bode well for you.


If you come up with a conclusion first then examine the evidence, that's not skepticism but either denial or politically-driven science (which should not count as real science).
Member Since: Posts: Comments:
000
FXCA62 TJSJ 070240
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1040 PM AST TUE APR 6 2010

.UPDATE...THE DOPPLER RADAR IS SHOWING ISOLATED TO SCATTERED
SHOWERS MOVING ACROSS THE LOCAL WATERS TONIGHT. SOME OF THESE
SHOWERS ARE AFFECTING THE NORTHERN U.S. VIRGIN ISLANDS AND SIMILAR
WEATHER CONDITIONS WILL AFFECT THE EASTERN PORTIONS OF PUERTO RICO
MAINLY THE NORTHEAST SECTIONS OF THE ISLAND THOUGH WEDNESDAY
MORNING. SLIGHT CHANGES WERE DONE TO THE WEATHER PACKAGE.

&&

.AVIATION...PREVAILING VFR CONDITIONS ARE EXPECTED ACROSS THE TAF
SITES FOR THE NEXT 24 HOURS IN A ENE LLVL WIND FLOW OF 15 TO 20
KNOTS...WITH GUSTS TO 25 KNOTS ACROSS THE VI...TJSJ AND TJBQ AFT
07/14Z.


&&

.PREV DISCUSSION... /ISSUED 350 PM AST TUE APR 6 2010/

SYNOPSIS...ELONGATED MID-UPPER LEVEL TROF WILL PULL TO THE
NORTHEAST TOMORROW AND BE REPLACED BY MID UPPER LEVEL RIDGING ON
THU THAT SHOULD HOLD THROUGH SAT. HIGH PRES NORTH OF THE BAHAMAS
WILL SHIFT EAST TOMORROW WITH A TIGHTENING OF THE PRES GRADIENT
AND A STRENGHTENING OF THE TRADE WINDS.

DISCUSSION...LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE RIDGE
AXIS ACROSS HISPANIOLA AHEAD OF S/W TROUGH NOW OVER ERN CUBA AND
JAMAICA. THIS S/W RIDGE AXIS WILL MOVE OVER PR THIS EVENING WITH A
RAPID DISSIPATION OF THE SHOWERS AND CLOUDS. MODELS SHOW S/W TROUGH OVR
ERN CUBA AND JAMAICA RACING EWD OVERNIGHT WITH AXIS OVR PR AT 12Z
TOMORROW. HOWEVER...MODELS ARE NOT VERY EMPHATIC WITH PRECIP
TOMORROW MORNING AS THEY WERE YESTERDAY WITH ALL AVAILABLE
GUIDANCE INDICATING STRONG SUBSIDENCE AND DRYING AS SEEN IN PWAT
AND K INDEX TIME SERIES PLOT. FOR TONIGHT...KEPT ISOLD POPS OVR
WATERS BUT NONE OVER LAND.

MID UPPER LEVEL HIGH WILL BUILD ON THU WITH MODELS MAINTAINING A
DECENT CAP THROUGH FRI. TIGHTENING PRES GRADIENT ASSOCIATED WITH
SHIFTING SFC HIGH WILL RESULT IN INCREASING TRADE WINDS THAT
SHOULD LIMIT SEA BREEZE DEVELOPMENT OVER THE NEXT COUPLE OF DAYS.
ANY ACTIVITY WILL BE LIMITED AND TIED TO THE DIURNAL HEATING
CYCLE. CAP WEAKENS/LIFTS TO 700 MB FRI WITH PERHAPS A BIT MORE
ACTIVITY.

BY SAT AFTERNOON...MODELS INDICATE COMPLETE EROSION OF THE MID
LEVEL CAP AS MID-UPPER LEVEL RIDGE SHIFTS EAST AND REGION START
BECOMING UNDER THE INFLUENCE OF DEEP UPPER LEVEL TROF ACROSS THE
NW ATLC. RELAXATION OF THE PRES GRADIENT WILL ALLOW FOR SEA BREEZE
DEVELOPMENT WITH SCT DEEP CONVECTION EXPECTED FOR SAT AND SUN.
STRONG SYNOPTIC FORCING WILL STILL BE LACKING FOR ANY LONG LASTING
PERIOD OF HEAVY RAINFALL.

MODELS SHOW AN INVERTED SFC TROF PATTERN SETTING UP ACROSS THE
GREATER ANTILLES NEXT WEEK WITH THE 12Z ECMWF MUCH FASTER THAN
THE GFS WITH THE ONSET OF THIS PRESSURE PATTERN. EUROPEAN ALSO
SHOWS MID-UPPER TROF DEEPENING ACROSS THE WRN ATLC AND EVENTUAL
EVOLUTION INTO A CUTOFF LOW NW OF THE AREA. GFES MEANS NOT AS
AGRESSIVE MAINTANING JUST AN OPEN TROF BUT SOME GFS MEMBERS ARE
ALSO INDICATING EVENTUAL EVOLUTION INTO THIS UPPER LEVEL PATTERN.
DEFINITELY SOME DIFFERENCES STILL EXIST IN TIMING AND EVOLUTION
OF THIS PATTERN THAT WILL STILL NEED TO BE RESOLVED OUT BUT A
SITUATION TO MONITOR CLOSELY OVER THE NEXT FEW DAYS AS THE
EUROPEAN SOLUTION WOULD BE ONE FOR HEAVY LONG LASTING FLASH
FLOODING RAINS. THE LATEST MJO ANALYSIS SHOWS THAT THE MJO HAS
BEEN PROPAGATING EWD ACROSS THE WESTERN PACIFIC WITH DYNAMICAL AND
STATISTICAL MODELS INDICATING INCREASING UPPER LEVEL DIVERGENCE
ACROSS THE CARIBBEAN DURING THE MIDDLE OF THE MONTH. SO THE BASIC
TREND HERE IS FOR MUCH WETTER CONDITIONS NEXT WEEK THAN WE HAD
RECENTLY EXPERIENCED.

AVIATION...BRIEF MVFR CIGS AND VSBYS WILL REMAIN POSSIBLE ACROSS
TJPS AND TJMZ THROUGH 06/23Z IN A VCSH OR PASSING SHRA. PREVAILING
VFR CONDITIONS ARE EXPECTED ACROSS THE REMAINDER OF THE TAF SITES
FOR THE NEXT 24 HOURS IN A ENE LLVL WIND FLOW OF 15 TO 20
KNOTS...WITH GUSTS TO 25 KNOTS ACROSS THE VI...TJSJ AND TJBQ AFT
07/14Z.

MARINE...SCEC STATEMENTS DUE TO INCREASING WINDS. SCA NOW IN
EFFECT FOR AMZ710 DUE TO 6-8 FT EASTERLY WIND WAVES.

FIRE WEATHER...THE INCREASING THE LOW LVL MOISTURE AND THICK
CLOUD COVER HAVE DEFINITELY HELPED IN THE FIRE WX SITUATION THE
LAST TWO DAYS. HOWEVER...THE INCREASING WINDS NEXT COUPLE OF DAYS
WILL RESULT IN DRYING OF THE FUELS. THIS IN COMBINATION WITH THE
POOR VEGETATIVE HEALTH ACROSS THE SOUTH COASTAL PLAIN AND IN ST.
CROIX STILL POSES A FIRE DANGER THREAT.

CLIMATE...AS OF 3 PM AST...A RECORD 0.47 INCHES OF RAIN FELL AT THE
LUIS MUNOZ MARIN INTERNATIONAL AIRPORT IN SAN JUAN. THIS SURPASSED
THE PREVIOUS RECORD OF 0.28 INCHES THAT FELL ON APRIL 6 2002.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 84 74 85 / 50 20 10 10
STT 75 86 76 87 / 40 10 10 10

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&

There you go Chicklit. This could be terrible for Haiti.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting Chicklit:
I cannot believe three people on this site could spell skeptical wrong.
Anyway, is this wall of water going to hit the Lower Antilles?



"Sceptical" is the Canadian/British spelling. Isn't the cold front/Northeast Atlantic low moving northeast?
Member Since: Posts: Comments:
Wow, about 40 mm of rain tomorrow and 35 mm Thursday is expected from this storm at my location in S. Ontario, and of course we'll get a lot more if we get ANY thunderstorms which could in fact be severe.



That run from 00z GFS (wow, why am I up so late?) is somewhat scary. It brings the storms currently over Kansas over my location by Wednesday night.
Member Since: Posts: Comments:
Can you please copy and paste here?
Member Since: Posts: Comments:
Quoting VAbeachhurricanes:
Joe Bastardi just mopped the floor with a climatologist in a debate on the colbert report...


Where? I wanna see.

Edit: I guess it just happened.....I'll have to wait for it to show up on Youtube I guess.
Member Since: Posts: Comments:
Quoting Chicklit:
Care to elaborate hydrus? Evidence?
Google----weather.gov------go to the U.S. map at the bottom you will see Puerto Rico. Click and on the left hand side you will see ( area forecast discussion ). That should fill in the blanks.:)
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Joe Bastardi just mopped the floor with a climatologist in a debate on the colbert report...
Member Since: Posts: Comments:
Quoting Chicklit:
Care to elaborate hydrus? Evidence?
Give me a few minutes, and I will post.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting skepticall2:
This is why I took a hiatus from debating global warming. The left just denies everything you say and it makes a person very frustrated. They wonder why conservatives aren't as happy because they see what is going on.


It's not really about political viewpoints, which have no bearing on the existence of global warming. You could say that the Conservatives do the same thing. And the last time I checked, Conservatives are generally happier than Liberals (because they don't bother with solving social issues?), but get more Liberal with age...ENOUGH POLITICS!
Member Since: Posts: Comments:
Care to elaborate hydrus? Evidence?
One can hope but it's best to conserve.
Pottery's feeling the pinch after letting that snake into his cistern.
Member Since: Posts: Comments:
Quoting presslord:
844 well...the eloquence of the presentation, coupled with the uttelry unique graphic, convinces me...I'm sold...


Unique? I think not.



At this rate, we're heading into a period of warmth not seen since the mid-Miocene in a century, which is the time period that last closely matched our current CO2 concentrations.
Member Since: Posts: Comments:
I know that CSU comes out with their hurricane season forecast tomorrow,but is there an actual time is comes out?
Member Since: Posts: Comments:
911

"CO2 emitted by humans and animals is part of a closed loop - we cant emit more CO2 than we fix in food crops etc."

good point
Member Since: Posts: Comments:
Quoting Chicklit:
Looks like little in the way of rain for the Caribbean.
If you read the latest weather bulletin from Puerto Rico, there are big changes coming to that area. Maybe to big.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting Levi32:


It's lovely up here in the summer :)

Yeah I'm pretty sure I've always been the northernmost blogger. It's ironic that I love the tropics and yet I have never been out of my state lol.
ALL science is cool.....:)
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting JFLORIDA:
There is some rather severe weather ramping up in the planes. I think we could see a tornado outbreak tonight and over the next few days.
I hope not, we have areas here that are still recovering last round.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Looks like little in the way of rain for the Caribbean.
Member Since: Posts: Comments:
Quoting hydrus:
you are probably the northernmost blogger here. I hope to see Alaska someday. I have read quite a bit about the state parks there.


It's lovely up here in the summer :)

Yeah I'm pretty sure I've always been the northernmost blogger. It's ironic that I love the tropics and yet I have never been out of my state lol.

Correction: I am not the only Alaskan blogger. I have a WU blogger friend in Sterling, AKSnowLuvr, and there is one in Fairbanks I believe. Those two are farther north than me.
Member Since: Posts: Comments:
Quoting skepticall2:
Say you were driving one of those toyotas that weren't fixed. Say you driving on an empty road the gas peddle sticks and you eventually get to top speed then you run out of gas. Doesn't the car stay at top speed for a little bit then begin to slow down. Sounds about right. God forbid that happens though.


But in the climate analogy, the brakes still work early in the game until more lubrication (positive feedbacks) is applied to the brake pads, but once in a while a stone (negative feedback) becomes lodged in the axle/wheel system that slows it down periodically and the car may hit a boulder (Yellowstone supervolcanic eruption) that stops it momentarily but there are few on the road. Now, of course, the logical thing to do is to step on the brakes early to slow down the car. Imagine down the road there are downward slopes, which represent tipping points, then a cliff, which means catastrophic climate change, so we want to avoid the cliff.
Member Since: Posts: Comments:
The OLR remained higher than normal during March over the eastern Atlantic, meaning less cloud-cover, allowing more sunlight to reach the water, aiding in the continued warming of the SSTs there.

Member Since: Posts: Comments:
Quoting Chicklit:
I cannot believe two people on this site could spell skeptical wrong.
Anyway, is this wall of water going to hit the Lower Antilles?

I am anxious to see what the models have for that region tomorrow. Should be interesting.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
The IRI's analyses for March are in, and here are the MSLP anomalies for the Atlantic. The negative anomalies across the entire mid-Atlantic shows how strongly negative the NAO remained on average last month. The monthly NAO index value for the month of March was -0.88. February's was -1.98. The higher average value in March was due to a positive burst that we had in the middle of the month.



Member Since: Posts: Comments:
I cannot believe three people on this site could spell skeptical wrong.
Anyway, is this wall of water going to hit the Lower Antilles?

Member Since: Posts: Comments:
Quoting Levi32:


I live in Homer, Alaska.
you are probably the northernmost blogger here. I hope to see Alaska someday. I have read quite a bit about the state parks there.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting skepticall2:
Some people just don't understand cycles at all. If the Earth was supposed to be just one big average temperature sphere then they would find something else to complain about. Seriously the Earth has to go through cycles it is inevitable, to think it doesn't is just ignorant.

Doesn't this look like cycles? Also doesn't it look like the Earth has been much warmer than today? I know my SUV wasn't invented back then.

Image and video hosting by TinyPic


Of course there are cycles, but those occur over tens of millions of years while the current warming is occurring over decades and centuries. Read more about that "spike" early in the Tertiary period here: Link
Member Since: Posts: Comments:
Quoting StormW:


Hmm, warm anomaly of the Gulf Stream from New England to between Bermuda and Newfoundland to west of Greenland. Could an extratropical remnant of a hurricane travel up that anomaly this season?
Member Since: Posts: Comments:
Quoting Skyepony:
Drak~ Thanks..

Levi~ It's pretty obvious that shear doesn't increase alot & prevent hurricanes consistently in all El Nino years, as you pointed out..personally I experienced 3 during the El Nino year of 2004. That makes yet one more argument that that those maps doesn't show a permanent super el nino.

Your La Nina vs El Nino maps has much less to do with shear & more to do where the A/B high sets up during each event. Remember 2007 when Felix & the rest went due west, keeping south the strong high.. it's expected & has nothing to do with shear.

As for where the MDR is located it's actually drawn on both those maps as a black rectangle..& is stated as such in the figure description.

I hadn't realized it was an ensemble but my point they don't all agree as much as they could & they all don't show the same as you stated... I've seen different scenarios, some with much more shear or perhaps it was worked out for the projected actual shear unlike this one which is increased shear for each degree C increase. Long range models are usually not right on. NW passage wasn't suppose to open til 2050 at the earliest by the runs 15yrs ago.


VAbeachhurricanes~ what personal insults? I like Levi. We can have a friendly debate for fun if we want.. Many times we both learn something from it.
Member Since: Posts: Comments:
Quoting hydrus:
where is us located?


I live in Homer, Alaska.
Member Since: Posts: Comments:
Quoting Levi32:


No this one's headed up into the Bering Sea where it will stall and dissipate by day 6. It's winding up nicely for this time of year but nothing out of the ordinary for us.
where is us located?
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting JFLORIDA:
Myths and falsehoods from the assault on global warming science

MYTH: The scientific consensus on global warming has been undermined by recent events

MYTH: Erroneous Himalayan glacier statement in IPCC report undermines evidence of global warming

MYTH: IPCC report was wrong about the Amazon and drought

MYTH: New study debunks link between global warming and hurricane intensity

MYTH: CRU director Jones admitted that global warming stopped in past 15 years

MYTH: CRU scientists "destroyed" raw temperature data

MYTH: Scientists "fudged" data with a "trick" to "hide" temperature "decline"

MYTH: NASA admitted its data "are in even worse shape" than CRU data

MYTH: CRU scientists "suppressed" opposition

MYTH: The Earth has been cooling since 1998

MYTH: Snowstorms prove global warming does not exist


More here: Skeptical science
Member Since: Posts: Comments:
Quoting Levi32:
Today's CFS run is still showing a negative NAO in September and lower-than-normal pressures across the SW Atlantic, Caribbean, and Gulf of Mexico.

Perplexing to me though is its forecast for a negative SOI despite a La Nina signal in the SSTs.

I think we will all be perplexed a few times by the end of the year. The weather is already doing weird crap, it will probably just keep getting weirder as the seasons change..
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting skepticall2:


So the whole part about how the individuals manipulated data or hid data doesn't hurt the cause?

Also where did I exactly say that climategate was related to the IPCC? I didn't there you go again putting words in my mouth. How are those glaciers going?


"Climategate" was used as a political decoy to feed the denial machine. And the "Glaciergate" thing only disproved ONE finding, which serves to improve the science rather than discredit it, because updating dispoven information and removing false assumptions is how science works and progresses. The tabloid press has blown all of this FAR out of proportion.
Member Since: Posts: Comments:
Quoting winter123:
99W actually looking pretty good. And real nasty storm headed for alaska.
Link
Quoting hydrus:
That storm headed for Alaska looks gigantic. I wonder if it will effect the lower 48?


No this one's headed up into the Bering Sea where it will stall and dissipate by day 6. It's winding up nicely for this time of year but nothing out of the ordinary for us.
Member Since: Posts: Comments:
The CFS 500mb for September does not look friendly with the blocking over SE Canada and a negative NAO look across the entire Atlantic, appropriately reflecting the surface pressures. This kind of a pattern can lead to many U.S. landfalls.


Member Since: Posts: Comments:
Quoting winter123:
99W actually looking pretty good. And real nasty storm headed for alaska.
Link
That storm headed for Alaska looks gigantic. I wonder if it will effect the lower 48?
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Quoting AstroHurricane001:


Wow...more Wikipedia articles to work on.
Not if you are one of those dead people in Brazil.
Member Since: September 27, 2007 Posts: 1 Comments: 19504
Today's CFS run is still showing a negative NAO in September and lower-than-normal pressures across the SW Atlantic, Caribbean, and Gulf of Mexico.

Perplexing to me though is its forecast for a negative SOI despite a La Nina signal in the SSTs.

Member Since: Posts: Comments:
901

Interesting loop. Looks like a meso scale convective complex in central Australia.
Member Since: Posts: Comments:
99W actually looking pretty good. And real nasty storm headed for alaska.
Link
Member Since: July 29, 2006 Posts: 28 Comments: 1762

Viewing: 955 - 905

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46Blog Index

Top of Page

About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.