Hurricanes and Climate Change: Huge Dangers, Huge Unknowns

By: Dr. Jeff Masters , 9:57 AM GMT on August 05, 2013

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Hurricane Sandy's enormous $65 billion price tag put that great storm in third place for the most expensive weather-related disaster in U.S. (and world) history, and six of the ten most expensive U.S. weather-related disasters since 1980 have been hurricanes. Thus, how the strongest hurricanes may be affected due a changing climate is a topic of critical concern. Since hurricanes are heat engines that extract heat energy from the oceans to power themselves, hurricane scientists are confident that the very strongest storms will get stronger by the end of the century, when Earth's land and ocean temperatures are expected to warm 2 - 3°C, to levels unmatched since the Eemian Era, 115,000 years ago. Computer modeling work consistently indicates that greenhouse warming will cause the globally averaged intensity of tropical cyclones to shift towards stronger storms, with intensity increases of 2–11% by 2100. But hurricanes are fussy creations, and are sensitive to wind shear and dry air. Although the strongest storms should get stronger when "perfect storm" conditions are present, these "perfect storm" conditions may become less frequent in the future, due to the presence of higher wind shear, altered atmospheric circulation patterns, or more dry air at mid levels of the atmosphere. Indeed, the climate models used to formulate the 2007 IPCC report suggested that we might see the strongest hurricanes getting stronger, but a decrease in the total number of hurricanes in the Atlantic (and worldwide) later this century. However, the latest set of models used to formulate the 2013 IPCC report left open the possibility that we might see in increase in the total number of hurricanes, and and increase in their intensity. Given the conflicting model results, we really don't know how global warming will affect the number of hurricanes and their intensity, but we run the risk of making one of humanity's greatest scourges worse.


Figure 1. The list of most expensive U.S. weather-related disasters since 1980 is dominated by hurricanes.

Climate models and hurricane frequency
The database we have on historical hurricanes does not extend far enough into the past and is not of high enough quality to make many judgements on how human-caused climate change may be affecting these great storms. A landmark 2010 review paper, "Tropical Cyclones and Climate Change", authored by ten top hurricane scientists concluded that the U.S. has not seen any long-term increase in landfalling tropical storms and hurricanes, and that "it remains uncertain whether past changes in tropical cyclone activity have exceeded the variability expected from natural causes" (tropical cyclone is the generic term which encompasses tropical depressions, tropical storms, hurricanes, and typhoons.) Based in part on modeling studies using climate models run for the 2007 IPCC report, the scientists concluded that "it is likely that global mean tropical cyclone frequency will either decrease or remain unchanged owing to greenhouse warming." For example, one of the modeling studies the review paper quoted, Knutson et al. (2008), "Simulated reduction in Atlantic hurricane frequency under twenty-first-century warming conditions", projected a decrease in Atlantic tropical storms by 27% and hurricanes by 18% by the end of the century. An important reason that their model predicted these decreases 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.

But a July 2013 study by MIT's Dr. Kerry Emanuel, "Downscaling CMIP5 climate models shows increased tropical cyclone activity over the 21st century", challenged this result. Dr. Emanuel argued that tropical cyclones are likely to become both stronger and more frequent as the climate continues to warm. This increase is most likely to occur in Western North Pacific, with smaller increases in the Atlantic. Dr. Emanuel took output from six newer higher-resolution climate models used to formulate the 2013 IPCC report, and used the output to drive a high-resolution hurricane model. The simulations found that the global frequency of tropical cyclones would increase by 11% to 40% by 2100, with intensity increases as well. The combined effects produced a global increase in Category 3 and stronger hurricanes of 40%. The behavior of these strongest hurricanes is critical, since they do most of the damage we observe. Over the past century, Category 3 - 5 hurricanes accounted for 85% of US hurricane damage, despite representing only 24% of U.S. landfalling storms. 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, see Pielke et al., 2008.)


Figure 2. Projected changes in tropical cyclone track density during the 2006-2100 period compared to the 1950-2005 period, using output from six climate models included in the 2013 IPCC report. The global frequency of tropical cyclones is predicted to increase by 11% to 40%, with the largest changes occurring in the Northwest Pacific off the coast of Japan. Smaller increases are predicted for the Atlantic and near Australia. Image credit: Kerry Emanuel, "Downscaling CMIP5 climate models shows increased tropical cyclone activity over the 21st century", Proceedings of the National Academy of Sciences, July 8, 2013, doi: 10.1073/pnas.1301293110.

However, a study by Knutson et al. (2013), using the same latest-generation climate models as used by Emanuel (2013), but using the output from the models to drive a different high-resolution hurricane model, found a 20% decrease in Atlantic tropical storms and hurricanes by 2100. Two other 2013 studies by Villarini et al. and Camargo, also using output from the 2013 IPCC models, found essentially no change in Atlantic tropical cyclones. The reason for the differences, lies, in part, with how much global warming is assumed in the studies. Dr. Emanuel's study, which found an increase in tropical cyclone activity, assumed a worst-case warming situation (RCP 8.5), following the "business as usual" emissions path humanity is currently on. The Knutson et al. study, which found a decrease of 20% in Atlantic tropical cyclones, used a scenario (RCP 4.5) where it was assumed humans will wise up and cause about half of the worst-case greenhouse warming. The study found found "marginally significant" increases in Atlantic Category 4 and 5 hurricanes of 39% - 45% by 2100. These dramatically different results give credence to Dr. Emanuel statement at the end of his paper, "the response of tropical cyclones to projected climate change will remain uncertain for some time to come." The 2013 IPCC report also emphasized the high amount of uncertainty in how climate change might affect hurricanes, stating that there was "low confidence" that we have observed any increases in intense tropical cyclones due to human causes. However, since the 1970s, it is virtually certain (99 - 100% chance) that the frequency and intensity of hurricanes and tropical storms in the North Atlantic has increased, and there is medium confidence that a reduction in small air pollution particles (aerosols) over the North Atlantic caused part of this effect. The report's forecast for the future stated that it is "more likely than not" (50 - 100% chance) that human-caused climate change will cause a substantial increase in intense tropical cyclones in some ocean basins by 2100, with the Western North Pacific and Atlantic being at particular risk. Also, there will likely (66 - 100% chance) be an increase in both global mean tropical cyclone maximum wind speed and rain rates by 2100, and more likely than not (50 - 100% chance) that the increase in the most intense tropical cyclones will be larger than 10% in some basins.


Figure 3. Expected change in Atlantic Category 4 and 5 hurricanes per decade expected by the year 2100, according to Knutson et al. (2013), "Dynamical Downscaling Projections of 21st Century Atlantic Hurricane Activity: CMIP3 and CMIP5 Model-based Scenarios." This research used the latest generation of climate models from the 2013 IPCC report, and found "marginally significant" increases in Atlantic Category 4 and 5 hurricanes of 39% - 45% by 2100.

Commentary
Hurricane damages are currently doubling every ten years without the effect of climate change, 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. Thus, by 2015, the same hurricane would do $300 billion in damage, and $600 billion by 2025. This is without considering the impact that accelerating sea level rise will have on storm surge damages. Global sea level rise over the past decade has been about double what it was in the 20th century, and the rate of sea level rise is expected to increase further in the coming decades. Storm surge does the majority of damage in major hurricanes, and storm surges riding on top of higher sea levels are going to do a lot more damage in the coming decades. If we toss in the (controversial) increases in Category 3 and stronger storms like Dr. Emanuel suggests may occur, the hurricane damage math gets very impressive. We can also add onto that the relatively non-controversial increase in tropical cyclone rainfall of 20% expected by 2100, which will sharply increase damages due to fresh water river flooding. It is controversial whether or not we are already be seeing an increase in heavy precipitation events associated with tropical cyclones in the U.S., though. The total number of daily rainfall events exceeding 2" associated with tropical cyclones in the Southeast U.S. on a century time scale has not changed significantly, according to Groisman et al., 2004. But a 2010 study by Kunkel et al., "Recent increases in U.S. heavy precipitation associated with tropical cyclones", found that the number of Southeast U.S. tropical cyclone heavy precipitation events, defined as 1-in-5-year events, more than doubled between 1994 - 2008, compared to the long-term average from 1895 - 2008.


Figure 4. Time series of the 15-year running average (plotted at the end point of the 15-yr blocks) of a Tropical Cyclone Heavy Precipitation Index (red) and 15-year running average of U.S. landfalling hurricanes (blue). Note that there has been no long-term increase in U.S. landfalling hurricanes, but there has been a sharp increase in extreme rainfall events associated with landfalling tropical cyclones--the kind of rainfall events most likely to cause damaging flooding. Image credit: Kunkel et al. (2010), "Recent increases in U.S. heavy precipitation associated with tropical cyclones", Geophysical Research Letters.

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 in the future. Adoption and enforcement of strict building standards is also a must, as well as more reforms to the government's National Flood Insurance Program (NFIP), which subsidizes development in high-risk coastal regions that private insurers won't touch. NFIP is now $25 - 30 billion in the red, thanks to Hurricane Katrina and Hurricane Sandy. Reform of NFIP is already underway. In 2012, before Sandy hit, Congress passed the Biggert-Waters Flood Insurance Reform Act, which requires people with NFIP policies to pay large premium increases of about 25% per year over the next five years. Naturally, this move has caused major controversy.

References
Camargo, S., (2013), "Global and regional aspects of tropical cyclone activity in the CMIP5 models," J. Climate.

Emanuel, K.A., 2013, "Downscaling CMIP5 climate models shows increased tropical cyclone activity over the 21st century", PNAS, July 8, 2013, doi: 10.1073/pnas.1301293110

Groisman, Pavel Ya, et al., "Contemporary changes of the hydrological cycle over the contiguous United States: Trends derived from in situ observations," Journal of Hydrometeorology 5.1 (2004): 64-85.

Knutson et al., 2010, "Tropical Cyclones and Climate Change", Nature Geoscience 3, 157 - 163, Published online: 21 February 2010 | doi:10.1038/ngeo779

Knutson et al., 2013, Dynamical Downscaling Projections of 21st Century Atlantic Hurricane Activity: CMIP3 and CMIP5 Model-based Scenarios, Journal of Climate 2013 ; e-View
doi: http://dx.doi.org/10.1175/JCLI-D-12-00539.1

Pielke, R.A, et al., 2008, "Normalized Hurricane Damage in the United States: 1900 - 2005," Natural Hazards Review, DOI:10.1061/ASCE1527-6988(2008)9:1(29)

Villarini, G, and G.A. Vecchi, 2012, "Twenty-first-century projections of North Atlantic tropical storms from CMIP5 models," Nature Clim. Change 2:604–607.

Related posts
Global warming and the frequency of intense Atlantic hurricanes: model results, my 2010 blog post.

Climate Central's analysis of the new 2013 Kerry Emanuel paper.

Goodbye, Miami: Jeff Goodell's sobering 2013 article in Rolling Stone on the challenges Miami faces due to sea level rise and hurricanes.


What the official climate assessments say about climate change and hurricanes
The 2013 IPCC report gives “low confidence”--a 20% chance--that we have observed a human-caused increase in intense hurricanes in some parts of the world. This is a reduction in odds from the 2007 report, which said that it was more likely than not (greater than 50% chance.) The IPCC likely took note of a landmark 2010 review paper, "Tropical Cyclones and Climate Change", authored by ten top hurricane scientists, which concluded that the U.S. had not seen any long-term increase in landfalling tropical storms and hurricanes, and that "it remains uncertain whether past changes in tropical cyclone activity have exceeded the variability expected from natural causes." The 2013 IPCC report predicts that there is a greater than 50% chance (more likely than not) that we will see a human-caused increase in intense hurricanes by 2100 in some regions; this is also a reduction from the 2007 report, which said this would be likely (66% chance or higher.)

The May 2014 United States National Climate Assessment found that “The intensity, frequency, and duration of North Atlantic hurricanes, as well as the frequency of the strongest (Category 4 and 5) hurricanes, have all increased since the early 1980s. The relative contributions of human and natural causes to these increases are still uncertain. Hurricane-associated storm intensity and rainfall rates are projected to increase as the climate continues to warm.”

Jeff Masters

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1. A single mature tree can absorb carbon dioxide at a rate of 22.7 kg/year (48 lbs) and release enough oxygen back into the atmosphere to support 2 human beings.

2. One acre of trees annually consumes the amount of carbon dioxide equivalent to that produced by driving an average car for 41,483km (26,000 miles). That same acre of trees also produces enough oxygen for 18 people to breathe for a year.

3. A 100-ft tree, 18" diameter at its base, produces 2721.5kg (6000lbs) of oxygen.

So, be conscious of the burden you put on ecosystems; reduce, reuse, and recycle- and remember to save every tree as if it’s the last.

Member Since: June 30, 2013 Posts: 11 Comments: 7464
I haven't read Dr M's references yet but given the propensity for drought prone areas to suffer from intensified droughts in the future, I expect there would be an increase in the SAL generating area - which would be a negative for hurricane frequency, at least.
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217. VR46L
Quoting 210. Tropicsweatherpr:
Interesting little area at 11N-45W.

Link


Hate to be a buzz killer but ... I see lots of dry air and the shear awaiting is just bad!

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Good Afternoon. Having a super-busy day today so just checking in during lunch.

In terms of Dr. Master's blog, the whole hurricane and climate change issue (and impact on future hurricane seasons) is basically pure speculation at this point. Not to say that these recent papers, thesis's, and computer modeling studies are not needed or justified but noting that we will not know which one of these actually confirm down the road........We just have to wait to see what happens although we have documented an increase in "major" hurricane frequency both in the Atlantic and Pacific basin in recent years.

In terms of the Atlantic basin, since around 80% of the hurricanes that threaten the Caribbean and US every year are Cape Verde systems, what happens in the future in terms of climate change impacts on the "engine" (the African Sahel/Sahara region where the waves originate), and the subsequent over water factors (Sal and Sheer Levels) is where we need to look closest in the coming decades.

High sheer and SAL could theoretically reduce the number of CV hurricanes in coming decades, but the ones that do form in any given season could be real monsters given higher sst's to take advantage of given less upwelling once they get close to the Caribbean and US.......Storm surge from higher sea levels is a totally different issue.
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Quoting 163. barbamz:

Next wave of thunderstorm attacks is developing in France (near Lyon). Will it reach me tonight? I'm sitting somewhere in the upper right section of the animation, lol. BBL.


Details see discusson on estofex.org


Il semble que les allemandes sont les unes en danger étant donné l'image satellite actuelle.
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Quoting 212. miguel617:

Not sure if this was posted yet. Cool rain storm.

Source... starts at 0:38s
That will put your eye out kid
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Quoting 201. NasBahMan:


Lake Travis normal capacity is 1.39 cu.km. while Lake O's normal capacity is 5.2 cu. km.....you do the math.


I just posted info about our lake, and how difficult it is to re-fill, compared to everybody else's lake. I never said anything about Lake O.
Member Since: August 4, 2007 Posts: 0 Comments: 3147

Not sure if this was posted yet. Cool rain storm.

Source... starts at 0:38s
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Quoting 205. TropicalAnalystwx13:

2, mainly.
Quoting 208. WPBHurricane05:
1 and 2 are typically the favorable phases for the Atlantic.
Ok thanks you guys.
Member Since: June 30, 2013 Posts: 11 Comments: 7464
Interesting little area at 11N-45W.

Link
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Quoting 170. Patrap:
Need a woman gonna hold my hand, won't tell me no lies, make me a happy man.

Quoting 170. Patrap:
Need a woman gonna hold my hand, won't tell me no lies, make me a happy man.

Pat......You seem to be very informed about some of the old hits....I know it's off topic, but if you care to discuss the oldies I am here...........Deja Vu
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1 and 2 are typically the favorable phases for the Atlantic.
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last frame on the 06z GFS for Africa..oh oh..train will be leaving the station..



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Quoting 202. SLU:


The weather today is far better with the SAL. The skies are 95% clear. :)

The CPL has been "Zouktastic". Last night's game was the best so far. lol.
I know I saw the score our guys must have drink too much El Dorado from the night before, missed the game, but Nigel was telling me I can catch them on ESPN3 I also can stream it. Looks like Barbados is leading the pack.
Member Since: June 30, 2013 Posts: 11 Comments: 7464
Quoting 196. GTstormChaserCaleb:
I was just about to ask, so what phase is Africa then? If it isn't 1 and 8?

2, mainly.
Member Since: July 6, 2010 Posts: 113 Comments: 31417
Quoting 172. mitchelace5:


Would the MJO also get into the Gulf of Mexico?

Nope. Won't fit.
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202. SLU
Quoting 194. GTstormChaserCaleb:
Hey SLU, How's the weather in St. Lucia? Have you been watching the CPL?


The weather today is far better without the SAL. The skies are 95% clear. :)

The CPL has been "Zouktastic". Last night's game was the best so far. lol.
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Quoting 181. redwagon:


Lake Travis is 63.75 miles long, and its maximum width is 4.5 miles. The lake covers 18,929 acres, and its capacity is 1,953,936 acre-feet. The lake is considered full at an elevation of 681.1 msl. At this elevation the lake contains 382,092,882,600 gallons of water. There are 270 miles of shoreline around the lake. It has a maximum depth of 210 and an average depth of 62 feet. The lakes historic high level is 710.4 feet msl on December 25, 1991. Its historic low level is 614.2 feet msl on August 14 1951.

Lake Travis was created by the impounding of the Colorado River by the construction of Mansfield Dam in 1937- 41. The dam is 266.41 feet high. The length is 7,089.39 feet. At the base it is 213 feet thick. Ranch Road 620 built on top of the dam and the adjoining protective walls bring the actual height of the dam to 274 feet. The top of the dam is 750 feet msl. Its spillway elevation is 714 feetmsl. At this elevation the lake contains 636,691,999,536 gallons of water. It has 3 Pen Stocks which divert water to 3 turbines with a total electrical generating capacity of 93,000 kw. The Dam has 24 floodgates at 4,770 cfs each. Each floodgate is 8.5 feet in diameter.

http://laketravis.com/about/


Lake Travis normal capacity is 1.39 cu.km. while Lake O's normal capacity is 5.2 cu. km.....you do the math.
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Quoting 196. GTstormChaserCaleb:
I was just about to ask, so what phase is Africa then? If it isn't 1 and 8?

1 and 8 is Atlantic and Africa

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Alright buddy, this isn't high school, fighting over lake size is a bit trivial.


i don't see any fighting....although mt is correct....and i enjoy reading correct material
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AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE JACKSONVILLE FL
948 AM EDT MON AUG 5 2013

CORRECTED WORDING FOR LOCATION OF STRONG STORMS THIS AFTERNOON

.UPDATE...
MORNING SOUNDING AT JAX DEPICTS DRIER MID AND UPPER LEVEL AIR
ALREADY IN PLACE BEHIND A DEPARTING SHORTWAVE. AT THE SURFACE...A
VERY WEAK FRONT IS CURRENTLY ANALYZED JUST NORTH OF THE
FLORIDA/GEORGIA BORDER. THIS FRONT WILL WASH OUT ACROSS NORTHEAST
FLORIDA BY THIS EVENING. WINDS ARE ALREADY STARTING TO SHIFT TO
THE NORTHEAST ACROSS THE ADJACENT SOUTHEAST GEORGIA WATERS. THIS
WILL HELP TO PUSH THE ATLANTIC SEABREEZE INLAND THIS AFTERNOON.
BETWEEN THE DIFFUSE FRONTAL BOUNDARY AND DEVELOPING
SEABREEZES...ENOUGH FORCING WILL BE AVAILABLE TO SUPPORT SOME
THUNDERSTORM ACTIVITY TODAY...BUT THE DRIER AIR ALOFT AND LACK OF
UPPER LEVEL ENERGY WILL KEEP THUNDERSTORM COVERAGE NO WORSE THAN
SCATTERED...WITH A FOCUS ACROSS OUR NORTHEAST FLORIDA ZONES. WILL
LIMIT POPS TO 20% OR LESS THE REST OF THE MORNING AND THEN SHOW AN
INCREASE TO 20-30% IN SE GA AND 40-50% ACROSS NORTHEAST FLORIDA
LATER THIS AFTERNOON. A FEW STRONG STORMS WILL BE POSSIBLE ACROSS
THE INTERIOR OF NORTHEAST FLORIDA AS MESOSCALE BOUNDARIES COLLIDE
LATE THIS AFTERNOON. STRONG GUSTY WINDS WILL BE THE PRIMARY CONCERN
GIVEN THE DRIER AIR ALOFT...BUT SOME LOCALLY HEAVY RAINFALL CAN ALSO
BE EXPECTED DUE TO SLOWER STORM MOTION. TEMPS TODAY WILL RANGE FROM
THE UPPER 80S AT THE BEACHES TO THE LOWER TO MIDDLE 90S INLAND. HEAT
INDICES WILL TOP OUT AROUND 100 TO 105 DEGREES.

&&
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Quoting 184. Matt74:
Might not be an active cape verde season like a lot of people are saying
Give it some time, September is not far away. Although it would be pretty amazing if it got as active as the last 3 years.
Member Since: June 30, 2013 Posts: 11 Comments: 7464
Quoting 179. TomTaylor:
Phase 1. Phase 8 is centered mostly over the EPAC and Central America region. Phases 1 and 2 will produce the greatest activity in our basin, though the MJO is no longer centered on our basin by phase 2.
I was just about to ask, so what phase is Africa then? If it isn't 1 and 8?
Member Since: June 30, 2013 Posts: 11 Comments: 7464
Quoting 170. Patrap:
Need a woman gonna hold my hand, won't tell me no lies, make me a happy man.

Black Dogs.I was chastised for quoting a song a few days ago.Deja Vu Pat
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Quoting 183. SLU:
Trade winds are weak leading to enhanced vorticity in the CATL. 12n 44w.

Hey SLU, How's the weather in St. Lucia? Have you been watching the CPL?
Member Since: June 30, 2013 Posts: 11 Comments: 7464
Quoting 181. redwagon:


Lake Travis is 63.75 miles long, and its maximum width is 4.5 miles. The lake covers 18,929 acres, and its capacity is 1,953,936 acre-feet. The lake is considered full at an elevation of 681.1 msl. At this elevation the lake contains 382,092,882,600 gallons of water. There are 270 miles of shoreline around the lake. It has a maximum depth of 210 and an average depth of 62 feet. The lakes historic high level is 710.4 feet msl on December 25, 1991. Its historic low level is 614.2 feet msl on August 14 1951.

Lake Travis was created by the impounding of the Colorado River by the construction of Mansfield Dam in 1937- 41. The dam is 266.41 feet high. The length is 7,089.39 feet. At the base it is 213 feet thick. Ranch Road 620 built on top of the dam and the adjoining protective walls bring the actual height of the dam to 274 feet. The top of the dam is 750 feet msl. Its spillway elevation is 714 feetmsl. At this elevation the lake contains 636,691,999,536 gallons of water. It has 3 Pen Stocks which divert water to 3 turbines with a total electrical generating capacity of 93,000 kw. The Dam has 24 floodgates at 4,770 cfs each. Each floodgate is 8.5 feet in diameter.

http://laketravis.com/about/


Alright buddy, this isn't high school, fighting over lake size is a bit trivial.
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Quoting 187. wunderkidcayman:

Actually it is 1and 8
2 is Indian Ocean

He said that...?
Member Since: July 6, 2010 Posts: 113 Comments: 31417
191. yoboi
Quoting 41. Naga5000:


Sorry VR46L, the numbers are accurate and strict methodology is used to correct for bias. This paper on the methodology used might be interesting to you. Link

Before attacking the data, maybe 5 minutes of research to understand what the data is saying and to see how it is calculated is in order.


The net effect of all biases appears to be an underestimation of average loss. In particular, it is shown that the factor approach can result in a considerable underestimation of average loss of roughly 10 to 15%. Because this bias is systematic, any trends in losses from tropical cyclones appear to be robust to variations in insurance participation rates. Any attribution of the marked increasing trends in crop losses is complicated by a major expansion of the federally subsidized crop insurance program, as a consequence encompassing more marginal land. Recommendations concerning how the current methodology can be improved to increase the quality of the billion-dollar disaster dataset include refining the factor approach to more realistically take into account spatial and temporal variations in insurance participation rates.


You can add another 10% with a weak US dollar......

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Quoting 185. iloveweather15:
need to watch it!


The wave on Central Africa in Chad is the one to watch down the road.
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Quoting 173. chrisdscane:
Great post Dr. M, lets remmember the earth cycles, who knows in 10 to 15 years we may be talking something diffrent, Global warmin is already a proven myth, never the less great post.
Could you please point me in the direction of that proof because, seriously, I would like to believe global warming is not happening.
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Quoting 179. TomTaylor:
Phase 1. Phase 8 is centered mostly over the EPAC and Central America region. Phases 1 and 2 will produce the greatest activity in our basin, though the MJO is no longer centered on our basin by phase 2.

Actually it is 1and 8
2 is Indian Ocean
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186. MTWX
Quoting 181. redwagon:


Lake Travis is 63.75 miles long, and its maximum width is 4.5 miles. The lake covers 18,929 acres, and its capacity is 1,953,936 acre-feet. The lake is considered full at an elevation of 681.1 msl. At this elevation the lake contains 382,092,882,600 gallons of water. There are 270 miles of shoreline around the lake. It has a maximum depth of 210 and an average depth of 62 feet. The lakes historic high level is 710.4 feet msl on December 25, 1991. Its historic low level is 614.2 feet msl on August 14 1951.

Lake Travis was created by the impounding of the Colorado River by the construction of Mansfield Dam in 1937- 41. The dam is 266.41 feet high. The length is 7,089.39 feet. At the base it is 213 feet thick. Ranch Road 620 built on top of the dam and the adjoining protective walls bring the actual height of the dam to 274 feet. The top of the dam is 750 feet msl. Its spillway elevation is 714 feetmsl. At this elevation the lake contains 636,691,999,536 gallons of water. It has 3 Pen Stocks which divert water to 3 turbines with a total electrical generating capacity of 93,000 kw. The Dam has 24 floodgates at 4,770 cfs each. Each floodgate is 8.5 feet in diameter.

http://laketravis.com/about/


That's fine, but Lake O holds 1.05 Trillion gallons of water...
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need to watch it!
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Quoting 151. GTstormChaserCaleb:
No orange is downward motion and green is upward motion. May in fact get a system in the Western Caribbean, GOM, or BOC before we see development in the far eastern Atlantic.
Might not be an active cape verde season like a lot of people are saying
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183. SLU
Trade winds are weak leading to enhanced vorticity in the CATL. 12n 44w.

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Quoting 5. Neapolitan:
No, inflation didn't contribute; note that the values in Figure 1 are given in 2013 dollars. Believe it or not, things really are as bad as they seem--and they're going to continue to get worse.

And, yes, it's our fault...


The methodology in accounting for inflation of damage estimates does not include the increase in population, the number of people living per household, the number of vehicles per person, etc. Even if the climate was not warming, it would continue to get worse (roughly in line with the population increase). So your prediction of weather related disasters becoming more expensive is an easy one to make...with or without a warming world.
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Quoting 177. NasBahMan:


Where are you getting your info from, Lake Travis while deep, at its normal capacity holds a third of the volume of Lake Okeechobee, Lake O is over capacity right now so it has over four times the water that Lake Travis can hold at full capacity, they are currently diverting or discharging over 2 billion gallons of water a day from Lake O.


Lake Travis is 63.75 miles long, and its maximum width is 4.5 miles. The lake covers 18,929 acres, and its capacity is 1,953,936 acre-feet. The lake is considered full at an elevation of 681.1 msl. At this elevation the lake contains 382,092,882,600 gallons of water. There are 270 miles of shoreline around the lake. It has a maximum depth of 210 and an average depth of 62 feet. The lakes historic high level is 710.4 feet msl on December 25, 1991. Its historic low level is 614.2 feet msl on August 14 1951.

Lake Travis was created by the impounding of the Colorado River by the construction of Mansfield Dam in 1937- 41. The dam is 266.41 feet high. The length is 7,089.39 feet. At the base it is 213 feet thick. Ranch Road 620 built on top of the dam and the adjoining protective walls bring the actual height of the dam to 274 feet. The top of the dam is 750 feet msl. Its spillway elevation is 714 feetmsl. At this elevation the lake contains 636,691,999,536 gallons of water. It has 3 Pen Stocks which divert water to 3 turbines with a total electrical generating capacity of 93,000 kw. The Dam has 24 floodgates at 4,770 cfs each. Each floodgate is 8.5 feet in diameter.

http://laketravis.com/about/
Member Since: August 4, 2007 Posts: 0 Comments: 3147
Quoting 169. redwagon:


GT, is that GOM potential home-grown? Or is it a long-tracker?
If I had to venture a guess because I too was also looking out in the Atlantic to see if anything formed there and nothing, so it probably comes from a Tropical Wave that interacts with an active monsoon trough in the Western Caribbean, similar to Barry.
Member Since: June 30, 2013 Posts: 11 Comments: 7464
Quoting 143. GTstormChaserCaleb:
Not a strong one, but in octants 1 & 8, the Atlantic is 8 right?

Phase 1. Phase 8 is centered mostly over the EPAC and Central America region. Phases 1 and 2 will produce the greatest activity in our basin, though the MJO is no longer centered on our basin by phase 2.
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178. wxmod
Russia fires. MODIS satellite swath.

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Quoting 74. HurricaneDevo:
For all of the talk earlier about piping water from flood areas to drought areas, such as Florida to Texas, I do not think people understand the differences in volume we are talking about.

Lake Okeechobee, while a very large lake, is very shallow, with an average depth of 9 feet. This gives the lake a total volume of 363 million gallons of water.

Lake Travis, in Texas, while smaller in area, has a much larger volume. Its total full volume, at normal levels, is 371 Billion gallons. Just to bring it to normal capacity from its current level would require 226 billion gallons of water.

So, even if we could pipe the entire lake from Florida to Texas, it would only be a drop in the bucket.

People who have never lived in the western United States do not understand the sheer size of the place when compared to the east, and how much water it would take to alleviate their massive drought.

Just my two cents.



Where are you getting your info from, Lake Travis while deep, at its normal capacity holds a third of the volume of Lake Okeechobee, Lake O is over capacity right now so it has over four times the water that Lake Travis can hold at full capacity, they are currently diverting or discharging over 2 billion gallons of water a day from Lake O.
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Quoting 166. mikatnight:


Except for Central America, it doesn't look good for anybody! And outside of creating State or National parks, you can forget about stopping people from moving towards the coast, money goes where money wants.

Yep, that is the unfortunate truth for the natural areas and for those of us who want to keep things serene.
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175. yoboi
Quoting 91. Neapolitan:
True. But the chart to which I referred (Figure 1) isn't just about hurricanes; you'll note it also includes drought and flood. And the science community is certain that such things will, indeed, continue to get worse.

Thanks to our profligate and unimpeded burning of fossil fuels, we've entered a narrowing one-way alley. A recent projection is that dealing with the effects of climate change will cost us the equivalent of the entire global economy. Even if things don't get anywhere near that bad, there'll likely come a day a few decades down the road that we'll look back with fondness and longing at a time when a disaster cost "only" $50 billion...



You are not looking at the true picture......you need to look at the US dollar compared with other world currency to get an accurate figure......it's not all about inflation......keep the printing machines going 24-7-365....I would advise people not to sleep during Economics 101.....I sincerly hope my contribution to the subject will guide you to post future acccurate numbers to the "REAL" cost for natural and man-caused disasters......
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Maldives - Island Kingdom under threat

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Great post Dr. M, lets remmember the earth cycles, who knows in 10 to 15 years we may be talking something diffrent, Global warmin is already a proven myth, never the less great post.
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Quoting 165. unknowncomic:
The MJO travels East. It will get to the Atlantic after the Caribbean.


Would the MJO also get into the Gulf of Mexico?
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Quoting 167. mitchelace5:


Nope. It'll kick off with either Erin or Fernand.
Member Since: August 1, 2011 Posts: 28 Comments: 7897
Need a woman gonna hold my hand, won't tell me no lies, make me a happy man.

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Quoting 138. GTstormChaserCaleb:
That is the empirical model which is based on climatology and if things were to propagate in a perfect manner. I was told to use the GFS or Euro MJO forecast.



GT, is that GOM potential home-grown? Or is it a long-tracker?
Member Since: August 4, 2007 Posts: 0 Comments: 3147

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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.