Is the Atlantic hurricane season getting longer?
It seems like there have been an unusual number of early and late season tropical storms and hurricanes in the Atlantic in recent years. In 2008, we had four named storms in July, and the second most powerful November hurricane on record. Both 2007 and 2005 had rare December storms, and 2003 featured Tropical Storm Anna, the first April tropical storm ever recorded. This year, Hurricane Tomas made 2010 the fourth straight year with a November hurricane, something that has never occurred in the Atlantic since accurate records began in 1851. Is hurricane season getting longer? Dr. Jim Kossin of the University of Wisconsin published a 2008 paper in Geophysical Research Letters, "Is the North Atlantic hurricane season getting longer?" He concluded that yes, there is a "apparent tendency toward more common early- and late-season storms that correlates with warming Sea Surface Temperature but the uncertainty in these relationships is high".
Figure 1. Observed sea surface temperature (SST) trends during the official North Atlantic hurricane season (June-November) for the period 1950-2007. Units are °C per century. The dashed rectangle denotes the tropical storm formation region south of 30° North latitude and east of 75° West longitude. Data are from the NOAA Extended Reconstructed Sea Surface Temperature V3 product [Smith et al., 2008]. Image credit: Kossin, J., 2008, "Is the North Atlantic hurricane season getting longer?", Geophysical Research Letters, Vol. 35, L23705, doi:10.1029/2008GL036012, 2008.
Methods
Dr. Kossin utilized the "best track" database of Atlantic tropical cyclone activity going back to 1851. However, since lack of satellite and aircraft reconnaissance data before 1950 makes the early part of this record suspect, he limited his analysis to the period from 1950 onward. The era of best data--the satellite era beginning in 1980--was also looked at separately, to ensure the highest possible data quality. The area studied was only a portion of the Atlantic--the tropical storm formation region south of 30° North latitude and east of 75° West longitude. This region has shown considerable warming of the Sea Surface Temperatures (SSTs) since 1950, in excess of 1°F (0.6°C) (Figure 1). A statistical method called "quantile regression" was employed. The method looked at how certain thresholds that mark the beginning and end of hurricane season have changed over the years. For example, the date where 5% of all tropical storms form earlier than that date, was called the 0.05 quantile, and the date where 5% of all tropical storms form later than that date, was called the 0.95 quantile. Kossin was able to show that the date of the 0.05 quantile got steadily earlier and the date of the 0.95 quantile steadily got later since 1950. Hurricane season for both the period 1950-present and 1980-present got longer by 5 to 10 days per decade.
Figure 2. Trends in tropical storm formation dates, in the region south of 30° North latitude and east of 75° West longitude, at the 0.05.0.95 quantiles. Trends are based on the periods (left) 1950-2007, and (right) 1980-2007. The dates (month/year) associated with the 0.05, 0.25, 0.50, 0.75, and 0.95 quantiles for each period are shown on the top axis (these threshold dates are based on the full sample for each period). Shading denotes the 90% confidence interval. Image credit: Kossin, J., 2008, "Is the North Atlantic hurricane season getting longer?", Geophysical Research Letters, Vol. 35, L23705, doi:10.1029/2008GL036012, 2008.
Relationship with Sea Surface Temperature
The broadening of the Atlantic hurricane season found was strongly dependent upon Sea Surface Temperatures. Both the onset and end of hurricane season shifted by 20 days per degree C of warming of the SST. With global warming projected to increase tropical Atlantic SSTs 1-2°C by the end of the century, can we then expect a 40-80 day increase in the length of hurricane season? Dr. Kossin doesn't explore this possibility, and doesn't blame the observed increase in the length of the season on human-caused global warming of the oceans. There is reason to believe that future warming of the Atlantic SSTs won't necessarily broaden the area over which tropical storms will form, though. Papers by Henderson-Sellers et al. (1998) and Knutson et al. (2008) theorize that as SSTs warm, the lowest temperature at which tropical storms can form will also increase. The current minimum temperature of 26.5°C (80°F) may increase to 28.5°C for a 2°C warming of Atlantic SSTs. Johnson and Xie (2010) have found observational evidence that the lowest temperature at which tropical storms can form has indeed been increasing at about 0.1°C per decade in the Atlantic, in line with climate model predictions.
References
Henderson-Sellers, A., et al., 1998, "Tropical Cyclones and Global Climate Change: A Post-IPCC Assessment", Bull. Am. Meteorol. Soc. 79, 19–38.
Johnson, N.C., and S.P. Xie, 2010, "Changes in the sea surface temperature threshold for tropical convection", Nature Geoscience doi:10.1038/ngeo1008
Knutson, T.R., J.J. Sirutis, S.T. Garner, G.A. Vecchi, and I.M. Held, 2008, Simulated reduction in Atlantic hurricane frequency under twenty-first-century warming conditions", Nature Geoscience 1, 359 - 364 (2008), doi:10.1038/ngeo202
Kossin, J., 2008, "Is the North Atlantic hurricane season getting longer?", Geophysical Research Letters, Vol. 35, L23705, doi:10.1029/2008GL036012, 2008.
Jeff Masters
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The Earth may in fact be growing.
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Tropical Cyclone Warning Number FIVE
DEPRESSION TROPICALE 04-20082009
4:00 AM Reunion December 17 2008
======================================
At 0:00 AM UTC, Tropical Depression (999 hPa) located at 10.8S 66.9E has 10 minute sustained winds of 30 knots with gust of 45 knots. The depression is reported as moving southwest at 7 knots.
Squally weather exist within 90 NM radius from the center extending up to 200 NM in the eastern semi-circle within a convergence line between 5S to 12S from 71E to 84E.
Near Gale-force winds 20 NM from the center
Dvorak Intensity: T2.5
Forecast and Intensity
=========================
24 HRS: 12.7S 65.4E - 35 knots (Tempete Tropicale Modere%uFFFD
48 HRS: 13.7S 63.2E - 25 knots (PERTURBATION TROPICALE)
72 HRS: 14.4S 61.1E - 25 knots (PERTURBATION TROPICALE)
Additional Information
======================
The deep convective cell existing since 1500z has probably allowed to intensify within the recent past 6 hours. TRMM 2001z swath confirms an existing low level circulation center under the main cluster (CF 37H), this system evolves within a neutral environment: Wind shear is weak, divergence is good poleward but weak equatorward, low level inflow is established poleward but remains weak equatorward. System is expected to keep on tracking southwest within the next 12 hours then recurve west-southwest on the northern edge of the subtropical high pressures.
A WINDOW EXIST FOR SOME INTENSIFICATION WITHIN THE NEXT 24 HOURS BEFORE NORTHERLY SHEAR BECOMES A LITLLE BIT STRONGER ON THE FRONT OF AN UPPER LEVEL TROUGH ON THE WEST OF THE SYSTEM. SYSTEM COULD REACH THE MINIMAL TROPICAL STORM STAGE.
The Day After (Inauguration)
By INVESTOR'S BUSINESS DAILY | Posted Monday, December 15, 2008 4:20 PM PT
Climate Change: The Associated Press warns that the new administration won't have much time to save the planet from a global warming apocalypse. Never mind that the "ticking time bomb" is a dud.
The temperature at Denver International Airport dropped to 18 below zero on Sunday, breaking the previous record of 14 below set in 1901. White Sulphur Springs, Mont., reported 29 below to the National Weather Service, breaking the record of 17 below set in 1922. Meanwhile, ice storms ravage the Northeast and the upper Midwest.
This is not a local phenomenon. Hong Kong had the second-longest cold spell since 1885. Cold in northern Vietnam destroyed 40% of the rice crop and killed 33,000 head of livestock. The British Parliament debated climate change as London experienced the first October snow since 1934.
Presumably this has all been reported by the Associated Press. But according to a weekend AP report, this is all an illusion and "2008 is on a pace to be a slightly cooler year in a steadily rising temperature trend line." Rather than being "evidence of some kind of cooling trend, it actually illustrates how fast the world is warming." Oh.
The report, which includes no comments from any skeptic, says global warming "is a ticking time-bomb that President-elect Obama can't avoid." It warns "warming is accelerating. Time is running out, and Obama knows it." Especially if he relies on AP wire reports.
Problem is, nature didn't get the memo. Geophysicist David Deming found that for the first time since the 18th century, in the days before SUVs, Alaskan glaciers grew this year instead of retreating. Fairbanks had its fourth coldest October in 104 years of records.
U.S. Geological Survey glaciologist Bruce Molnia reported: "On the Juneau Icefield, there was still 20 feet of new snow on the surface of the Taku Glacier in late July." It was the worst summer he'd seen in two decades.
As the Anchorage Daily News reports, "Never before in the history of a research project dating back to 1946 had the Juneau Ice Field witnessed the kind if snow buildup that came this year. It was similar on a lot of other glaciers too."
The consequence of melting glaciers and sea ice is supposed to be rising sea levels. The poster children for this phenomenon are low-lying coral islands such as the Maldives and Tuvalu. Again, the facts are ignored in the quest for headlines.
The satellite record shows the sea level has actually fallen four inches around Tuvalu since 1993, when the $100 million international TOPEX/POSEIDON satellite project record began.
As in other places around the world, sea-level changes have many natural explanations, including geologic changes in the land.
The atolls of Tuvalu rest on sinking volcanic rock on top of which new coral grows to replace the coral die-off that occurs as the volcanic rock sinks deeper into the ocean where coral does not survive. Sand is excavated for building material on Tuvalu. Excavation for building material has eroded the beach, thus giving to the casual, or biased, observer the impression of rising sea levels.
The strong El Nino of 1997-98 caused the sea level surrounding Tuvalu to drop just over one foot.
Patrick Michaels, a research professor of environmental sciences at the University of Virginia and visiting scientist with the Marshall Institute in Washington, D.C., notes that Tuvalu is near the epicenter of a region where the sea level has been declining for nearly 50 years. He has written that the decline has been so steep that, even accepting the U.N.'s median estimates of global warming over the next hundred years, Tuvalu would not return to its 1950 sea level until 2050, much less disappear under the sea.
None of this, of course, matters to the warming zealots and some major media outlets. If it's too dry or too wet, too hot or too cold, everything is caused by global warming. We believe, as do many reputable scientists, that the warming and cooling of the earth is a natural phenomenon dictated by forces beyond our control, from ocean currents to solar activity. We needn't worry about one day mooring our boats to the Washington Monument.
Those grandsons will always remember tonight.
Never miss the opportinity amigo.
Cheers AussieStorm
430 PM EST TUE DEC 16 2008
.SYNOPSIS...STRONG HIGH PRESSURE N OF THE AREA TONIGHT WILL
GRADUALLY WEAKEN THROUGH THU NIGHT. NON-TROPICAL LOW...1010
MB...NEAR 26N56W WILL TRACK SW TO WSW TO 25N62W WED AFTERNOON
AND OPEN UP INTO A TROUGH LATE THU OVER PUERTO RICO AND
HISPANIOLA.
Link
QuikScat showing circulation near 26N x 57W
Link
How current is this image? This is great for wind surfing!
ROFLMAO!!! headache time!!!
The broadening of the Atlantic hurricane season found was strongly dependent upon Sea Surface Temperatures. Both the onset and end of hurricane season shifted by 20 days per degree C of warming of the SST. With global warming projected to increase tropical Atlantic SSTs 1-2°C by the end of the century, can we then expect a 40-80 day increase in the length of hurricane season? Dr. Kossin doesn't explore this possibility, and doesn't blame the observed increase in the length of the season on human-caused global warming of the oceans. There is reason to believe that future warming of the Atlantic SSTs won't necessarily continue to broaden the length of hurricane season at the rate Kossin suggests has occurred. Papers by Henderson-Sellers et al. (1998) and Knutson et al. (2008) theorize that as SSTs warm, the lowest temperature at which tropical storms can form will also increase. The current minimum temperature of 26.5°C (80°F) may increase to 28.5°C for a 2°C warming of Atlantic SSTs. Furthermore, Kossin's results apply only to the Atlantic Ocean, and it is uncertain whether or not hurricane season is changing in length in other ocean basins. -Jeff Masters
Why is that?
and yes, i'm wishcasting.
Why is it that the threshold rises?
I could use some xmas tunes...but so reflective and worried for people. And our family too.
TROPICAL CYCLONE OUTLOOK WESTERN AUSTRALIA 110E-125E
Issued at 2:00pm WDT on Wednesday the 17th of December 2008
===========================================
A developing Tropical Low [1002 hPa] is situated north of the Kimberley in the Timor Sea. At midday it was near 12.5S 127.0E, about 220 km north-northeast of Kalumburu and moving towards the south at about 8 km/h. The low is expected to move slowly towards the southwest during the next few days, towards the north Kimberley coast.
Tropical Cyclone Development Potential
=====================================
Thursday: Low
Friday: High
Saturday: High
Tropical Cyclone Advice Number ONE
TROPICAL LOW (02U)
4:00 PM Austialia CST December 17 2008
=====================================
At 12:30 PM Australian CST, a Tropical Low [1004 hPa] located at 12.5S 127.0E, or 205 kilometres north northeast of Kalumburu and 420 kilometres west of Darwin has 10 minute sustained winds of 25-30 knots with gusts up to 45 knots. The low is reported as moving southwest at 7 knots towards Kimberley coast.
There is the possibility of a tropical cyclone developing close to the north Kimberley coast on Friday. GALES are not expected in coastal areas within the next 24 hours, however gales could develop later.
Tropical Cyclone Watch
=========================
A Cyclone WATCH has been declared for a developing tropical low for coastal and island communities from Cockatoo Island in WA to the Western Australia/Northern Territory Border.
BOM Darwin is showing a slight possibility of Tropical Cyclone Billy just before landfall
STS Rene?!
53F and forecast to be 70F today
Must be GW!!!!!!
Cloudy all day
Arctic sea ice extent in 2008 reached its second lowest melt season extent on record in September. The minimum of 1.74 million square miles (4.52 million square kilometers) reached on September 12 was 0.86 million square miles (2.24 million square kilometers) below the 1979-2000 average minimum extent.
The 2008 Atlantic hurricane season was the third most costly on record in current dollars, after 2005 and 2004, and the fourth most active year since 1944. This was the first season with a major hurricane (Category 3 or above) each month from July through November. With the exception of the South Indian Ocean, all other tropical cyclone regions recorded near to below-average activity during 2008. Globally, there were 89 named tropical cyclones, with 41 reaching the equivalent of hurricane strength (74 mph), and 20 achieving the equivalent of major hurricane status (111 mph or greater) based on the Saffir-Simpson scale.
The United States recorded a preliminary total of just under 1,700 tornadoes from January - November. This ranks 2008 second behind 2004 for the most tornadoes in a year, since reliable records began in 1953.
Torrential rains caused widespread flooding in parts of Vietnam, Ethiopia, northern Venezuela, Brazil, Panama, and the northern Philippines during November. Several million people were displaced and nearly 200 fatalities were reported. Monsoonal rainfall was much above average over many regions in 2008. Mumbai, India, recorded its greatest June rainfall in seven years, while Hanoi, Vietnam, observed its greatest October rains since 1984
Excluding the Paciffic and other oceans "may" lead to conjecture by opponents that either the SST's are not rising universely or either his theory is hogwash.
He should have completed his homework.
TROPICAL CYCLONE WATCH
TROPICAL CYCLONE ADVICE NUMBER 2
Issued by the BUREAU OF METEOROLOGY, DARWIN
at 11:10 pm Australian CST [10:40 pm WDT] Wednesday 17 December 2008
A Cyclone WATCH continues for a developing tropical low for coastal and island
communities from Cockatoo Island to WA/NT Border.
At 9:30 pm Australian CST [9:00 pm WDT] a Tropical Low was estimated to be 190 kilometres
north northeast of Kalumburu and 370 kilometres west of Darwin, moving slowly
south towards the Kimberley coast.
There is the possibility of a tropical cyclone developing close to the north
Kimberley coast on Friday. GALES are not expected in coastal areas within the
next 24 hours, however gales could develop later.
Details of Tropical Low at 9:30 pm CST [9:00 pm WDT]:
.Centre located near...... 12.8 degrees South 127.5 degrees East
.Location accuracy........ within 110 kilometres
.Recent movement.......... towards the south at 2 kilometres per hour
.Wind gusts near centre... 85 kilometres per hour
.Severity category........ below cyclone intensity
.Central pressure......... 1004 hectoPascals
The next advice will be issued by 5:00 am CST Thursday 18 December [4:30 am WDT
Thursday 18 December].
DARWIN Tropical Cyclone Warning Centre
Updated
Wednesday December 17, 2008 - 14:40 EDT
Oil and gas exploration workers have been evacuated from offshore rigs in preparation for a possible cyclone off the Western Australian coast.
The Bureau of Meteorology is monitoring a weak low between Timor and the Tiwi Islands, off the north Australian coastline.
The bureau says it could develop into a cyclone within the next few days.
Port authorities in Broome say four companies have begun moving workers from offshore rigs.
- ABC
Link
Isn't it amazing that every single "skeptic" as you like to call them, is funded by "Big Oil"? It's easy to dismiss something and say that it's automatically funded by some imaginary group, such as "Big Oil," rather than do the research and find out that it's from normal, every day climate scientists who just don't buy in to the load of garbage that media outlets like to report because it makes for some exciting headlines.
What's even more ridiculous is that you follow that up with a review on those climate scientists by referring us to a report from "The Daily Green." Hmm...that's a pretty objective source isn't it? I wonder where they get their funding from? Is there a "Big Solar" or "Big Green" out there that I can complain about?
Please save your ridiculous comments about "Big Oil" and how it funds everything with a view contrary to yours. I'm sure your Al Gore-led support group would be glad to hear them.
Source: Reuters
By Maggie Fox, Health and Science Editor
WASHINGTON, Dec 16 (Reuters) - Heat is more likely to kill an American than an earthquake, and thunderstorms kill more people than hurricanes do, according to a U.S. "death map" published on Tuesday.
Researchers who compiled the county-by-county look at what natural disasters kill Americans said they hope their study will help emergency preparedness officials plan better.
Heat and drought caused 19.6 percent of total deaths from natural hazards, with summer thunderstorms causing 18.8 percent and winter weather causing 18.1 percent, the team at the University of South Carolina found.
Earthquakes, wildfires and hurricanes combined were responsible for fewer than 5 percent of all hazard deaths.
Writing in BioMed Central's International Journal of Health Geographics, they said they hoped to dispel some myths about what the biggest threats to life and limb are.
"According to our results, the answer is heat," Susan Cutter and Kevin Borden of the University of South Carolina wrote in their report, which gathered data from 1970 to 2004.
"I think what most people would think, if you say what is the major cause of death and destruction, they would say hurricanes and earthquakes and flooding," Cutter said in a telephone interview. "They wouldn't say heat."
"What is noteworthy here is that over time, highly destructive, highly publicized, often-catastrophic singular events such as hurricanes and earthquakes are responsible for relatively few deaths when compared to the more frequent, less catastrophic such as heat waves and severe weather," they wrote.
The most dangerous places to live are much of the South, because of the heat risk, the hurricane coasts and the Great Plains states with their severe weather, Cutter said.
The south-central United States is also a dangerous area, with floods and tornadoes.
California is relatively safe, they found.
"It illustrates the impact of better building codes in seismically prone areas because the fatalities in earthquakes have gone down from 1900 because things don't collapse on people any more," Cutter said.
Merry Christmas everyone!
TampaSpins Weather Blog Link
Link
I just met Stormjunkie, Jr.
....quite a handsome young man....doesn't look a thing like his father....
Sophism exists in Science as well as Politics.
That's why we educate ourselves...LOL
Good news. Skips a generation, huh???
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