Reuters: Hurricane destruction powers global warming debate

[jasons2k]

I tried to post this in the GW thread that was going last week and I can't find it anymore - niot even in my post history. Strange indeed.....anyway, here is the article:

Hurricane destruction powers global warming debate
Tue May 2, 2006 9:23 AM ET

By Jim Loney

MIAMI (Reuters) - For a brief time in October, the pressure inside 185-mph (298 kph) Hurricane Wilma dropped to an astonishing low, making it the most intense hurricane ever recorded in the Atlantic and Caribbean.

That historic cyclone happened during a record-shattering hurricane season that produced 28 storms and occurred only weeks after Katrina swamped New Orleans, causing $80 billion in damage.

The ferocity of last year's season gave ammunition to a growing chorus of voices that says humans and their greenhouse gas-spewing cars and factories could be making hurricanes more destructive.

But it did nothing to convince a hard core of hurricane researchers who insist there's no evidence that people are responsible for the recent intensity, and growing numbers, of tropical cyclones.

The stakes are high. An estimated 50 million people live along the hurricane-vulnerable U.S. east and Gulf coasts.

Millions more live in flood-prone mountains in Haiti and Central America, where hurricanes take thousands of lives.

The U.S. hurricane tab last year was more than $100 billion. Major storms in the 2004 season caused another $45 billion in damage.

"The coastal regions are in jeopardy. The Miami area and the New Orleans area are very much at risk. We have a 10-year window to do something about greenhouse gases," said Prof. Judith Curry, chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology.

"STUNNING INCREASES"

Curry said leading scientists with published research have compelling evidence that human-induced global warming is heating the seas from which hurricanes draw their strength. In the North Atlantic -- as the Atlanic north of the equator is called -- that has increased both the number and intensity of hurricanes in the last decade, she said.

"They are stunning increases that are way outside the bounds of natural variability," she said.

Tropical ocean temperatures have risen about 1 degree Fahrenheit since 1970, said Curry. "This 1 degree is playing havoc with hurricanes. It's a lot of extra energy for these storms."

When Wilma's internal pressure hit 882 millibars, beating a record held by 1988's Gilbert, climatologists took notice. It was the first time a single season had produced four Category 5 hurricanes, the highest stage on the 5-step Saffir-Simpson scale of storm intensity.

The 28 tropical storms and hurricanes crushed the old mark of 21, set in 1933.

While some hurricane researchers accept that the sea is warming, they believe it's part of a natural cycle, rather than human-caused.

They say the Atlantic entered a period of heightened hurricane activity around 1995 and may not settle down for another 20 or 30 years due to a cycle called the "Atlantic multidecadal oscillation."

With hurricane records for only 150 years, some say there isn't enough historical data to blame the greenhouse effect.

"We don't have any facts because we don't have any long-term records," said Neil Frank, a former director of the U.S. National Hurricane Center.

The debate has taken center-stage among hurricane and climate scientists in the United States, where President George W. Bush's rejection of the Kyoto agreement to cut greenhouse gases enraged environmental groups and foreign nations.

Some U.S. scientists say Washington has stifled dissenters. Others deny it. "No one has put any pressure on me, from the White House or anywhere else," U.S. National Hurricane Center director Max Mayfield said.

GROWING EVIDENCE

After two of the worst seasons on record -- 2004 produced 15 storms -- U.S. researchers are speaking more boldly.

At an American Meteorological Society conference in Monterey, California, last week, a U.S. government researcher blamed last year's record season on global warming.

On the web site of the government's Geophysical Fluid Dynamics Laboratory, the subject is broached frankly.

"The strongest hurricanes in the present climate may be upstaged by even more intense hurricanes over the next century as the earth's climate is warmed by increasing levels of greenhouse gases....," it says.

Kerry Emanuel, a professor at the Massachusetts Institute of Technology, wrote in Nature magazine last August that the power dissipated by hurricanes in the North Atlantic has doubled in the last 30 years, possibly because storms have been more intense for longer periods of time.

"My results suggest that future warming may lead to an upward trend in tropical cyclone destructive potential," he wrote.

A study by Curry and her colleagues published in Science magazine last fall found the proportion of hurricanes reaching Category 4 and 5 has nearly doubled in the last 35 years.

But Frank, the former hurricane center director who now is a weatherman for KHOU television in Houston, said he does not believe hurricanes are more frequent or more intense than they were in the last warming period, in the 1930s, '40s and '50s.

Only since the 1970s have researchers had satellites that allow them to look directly at hurricanes. As a result, he believes, storms that might have escaped detection in mid-ocean decades ago are now tracked from birth to death.

Scientists who believe human-induced global warming is linked to hurricane formation and strength rely too heavily on numerical models, Frank said.

"These same numerical models that I can't put faith in for a two-week forecast, we're told can be accurate out 200 years," he said. "Ridiculous."

Whatever the outcome of the debate, forecasters say the damaging seasons of 2004 and 2005 could be just the beginning.

"I'm here to tell you it can get worse," Mayfield said.

[MiamiensisWx]

This is nothing new. Besides, Wilma may not even have the lowest Atlantic pressure of any Atlantic storm. It is possible that the Florida Keys 1935 Labor Day Hurricane had a lower pressure than Wilma and sustained winds just as high as Wilma at one point.

[Matt-hurricanewatcher]

The global tropical cyclones are way below avg this year.

[Tampa Bay Hurricane]

The Atlantic Multidecadal Oscillation is primarily responsible (natural), global warming's impacts are most likely slight additional increases in intensity...
but the atlantic multidecadal oscillation is the PRIMARY FACTOR WITH THE MOST SIGNIFICANT INFLUENCE. Global warming's influence on intensity is also likely present, but it is not a primary factor, and it's effects though are light to moderate, not very large in magnitude, relative to the other factors (Shear, SOI, AMO).

Natural cycles are the primary factors- global warming may be having effects small in magnitude...but natural factors can still cancel it out-- for instance...we did not see a severe WPAC or EPAC hurricane season this past year- the natural cycles and natural meteorological factors are primarily responisble..though global warmings influence, small in magnitude, on overall intensity over the past 40-50 years for all basins, cannot be ruled out...and is in fact likely having an impact SMALL in MAGNITUDE relative to NATURAL FACTORS.

[HurricaneBill]

I noticed Australia got hit by multiple and intense cyclones this season. Was that because of La Nina? I noticed that intense cyclones seem to hit Australia during La Ninas.

[MGC]

My main agrument, explain 1933 and the then record number of tropical cyclones. This without the use of satellite......MGC

[MiamiensisWx]

The Atlantic Multidecadal Oscillation is primarily responsible (natural), global warming's impacts are most likely slight additional increases in intensity...
but the atlantic multidecadal oscillation is the PRIMARY FACTOR WITH THE MOST SIGNIFICANT INFLUENCE. Global warming's influence on intensity is also likely present, but it is not a primary factor, and it's effects though are light to moderate, not very large in magnitude, relative to the other factors (Shear, SOI, AMO).

Natural cycles are the primary factors- global warming may be having effects small in magnitude...but natural factors can still cancel it out-- for instance...we did not see a severe WPAC or EPAC hurricane season this past year- the natural cycles and natural meteorological factors are primarily responisble..though global warmings influence, small in magnitude, on overall intensity over the past 40-50 years for all basins, cannot be ruled out...and is in fact likely having an impact SMALL in MAGNITUDE relative to NATURAL FACTORS.

I agree with your general points. I think global warming may be happening, but it is only very, very slight. Most to nearly all of the activity relies on cycles and other natural and variable factors.

[Audrey2Katrina]

I agree with your general points. I think global warming may be happening, but it is only very, very slight. Most to nearly all of the activity relies on cycles and other natural and variable factors.

I believe "global warming" is quite undeniable. How much of it is anthropogenic is what is debatable; as well as whether or not it is significant enough to be causing any vascillation in weather patterns as extreme as cyclonic activity. This, as of this time, is a scenario I don't buy into.

A2K

[gatorcane]

My main agrument, explain 1933 and the then record number of tropical cyclones. This without the use of satellite......MGC

1933 was active but way too many records were broken by 2005 - which makes me think it will not be an anomaly going forward.

The intense activity of 2005 could be a trend where global warming could be playing a factor.

[AussieMark]

I noticed Australia got hit by multiple and intense cyclones this season. Was that because of La Nina? I noticed that intense cyclones seem to hit Australia during La Ninas.

its do with ENSO

when a El Nino falls during our summer we get very few cyclones.

When Nino region 4 has anomalities in the positive cyclones numbers are usually down. as we say in 2002/03, 2004/05 to name 2 such years

The Niño-4 region is in the central Pacific, straddling the dateline. It goes from 160 East to 150 West, and from 5 South to 5 North

on the flipside when a La Nina is in effect we do normally see higher numbers of cyclones as was observed in the 1998/99 season

[Sanibel]

Today the New York Times printed a small article saying government scientists have come out and directly attributed the increase of storms and intensity to that 1 degree farenheit increase.




I checked the Unisys archive. 1933 had 5 majors. The maximum was 120 knots. The maximum was category 4.

2005 had more majors. Two set records for their basins. Two were over 150 knots. The maximum was category 5 with a new Atlantic low pressure record. And a new July intensity record.

[AussieMark]

1950 is still the record year with 8 majors and the strongest a 160 kt Hurricane

[Audrey2Katrina]

The intense activity of 2005 could be a trend where global warming could be playing a factor

Then again 2005 could also be an anomaly like 1933, most climatologists agree that the "trend" is upward... and no small number consider it a natural cycle.

A2K

[Audrey2Katrina]

Today the New York Times printed a small article saying government scientists have come out and directly attributed the increase of storms and intensity to that 1 degree farenheit increase.

To each his/her own, but I don't put a a whole lot of credibility in the NYT. Mind you, I don't doubt that this "small" article exists; but upon going to NYT online and searching EVERY article this day on the Global Warming topic (there were 11), I could find none that make this assertion. Interestingly there WAS a column of a finding by a study commissioned by the administration that concluded human induced global warming is fairly certain; but makes absolutley NO mention of hinging it to the increased cyclonic activity--just wasn't there. Additionally, they claim that this is only one of 21 more studies in the works. That there ARE scientists who make this claim, I don't dispute, you can find scientists who espouse both sides of any controversy... it's the ones who get the ink that are given most acceptance in the public forum. I KNOW that Dr. Gray who is quite a well reputed "scientist" and specifically in cyclonic activity, and he does not agree with this finding.

A2K