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Global warming fueled 2005 hurricane season NOT cyclical ocean cycles (AMO)
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| occrider |
Well it seems that science is finally putting an end to the debate about whether the particularly nasty hurricane season was due to global warming or naturally occurring due to the Atlantic Multidecadal Oscillation (AMO).
| quote: |
Study: Global Warming Fueled 2005 Hurricanes Ker Than
LiveScience Staff Writer
LiveScience.com
Fri Jun 23, 12:00 PM ET
Global warming, and not natural variations in ocean temperature, provided most of the fuel for last year's unusually strong hurricane season, scientists said this week.
The finding, detailed in the June 27 issue of Geophysical Research Letters, raises the risk of active hurricanes seasons in coming years, the researchers said.
Last year's North Atlantic hurricane season featured a record 27 named storms, so many that the World Meteorological Organization had to use letters from the Greek alphabet. The 2005 season also featured the most intense Atlantic storm ever recorded (Wilma), the most intense storm in the Gulf of Mexico (Rita) and the most damaging storm on record (Katrina); all three were Category 5 hurricanes at some point.
Beyond normal variations
The researchers, Kevin Trenberth and Daniel Shea of the National Center for Atmospheric Research (NCAR), focused on rising sea surface temperatures, or SSTs. When the ocean is warm, more water evaporates, providing fuel for a developing storm.
Other studies have linked rising SSTs in the Atlantic to a near doubling in the number of intense Category 4 and 5 hurricanes worldwide, from 10 a year in 1970 to about 18 a year since 1990.
During much of the 2005 season, SSTs in the Atlantic where hurricanes typically originate were 1.6 degrees Fahrenheit warmer than the 1901 to 1970 average.
Some scientists attribute the rising SSTs to global warming, but others, including hurricane experts at the National Oceanic and Atmospheric Administration (NOAA), have consistently argued that the increase can be fully explained by natural ocean cycles such as El Nino and the decades-long Atlantic Multidecadal Oscillation (AMO), both of which produce fluctuations in SSTs.
The study details
Using worldwide SST data since the early 20th century, Trenberth and Shea calculated the individual contributions of global warming and the AMO to Atlantic SSTs. They subtracted the irregular Atlantic temperatures from the temperature patterns in the rest of Earth's tropical and mid-latitude waters.
Their calculations show that about half, or 0.81 degrees Fahrenheit, of the Atlantic SST increase was due to global warming, while only 0.2 degrees owed to the AMO. The remainder of the increase could be explained by the aftereffects of the 2004-2005 El Nino and normal year-to-year variations in temperatures.
"We found the much hyped Atlantic Multidecadal Oscillation is important [to hurricane activity] but did not really contribute much to 2005," Trenberth told LiveScience.
"Any addition to the overall body of scientific know is important, but since we haven't had a chance to review the document, we really can't give a reaction to it," said NOAA spokesman Kent Laborde.
Another finding
The results also showed that the AMO is actually much weaker now than it was in the 1950s, during the last active hurricane period. The study does not discount the AMO's effect on hurricane activity, however, and finds that it contributed to the lull in Atlantic hurricane activity from about 1970 to 1990.
The researchers say that warming SSTs will raise the baseline for hurricane activity for coming years. This does not mean that each year will set new records for hurricanes, though. Every year will be different because the effects of natural temperature variations and other natural cycles will vary.
Rainfall in parts of Africa and high-level wind patterns can also fuel or throttle hurricane formation in a given season.
The bottom line, Trenberth said, is that "the fuel for hurricanes from water vapor from the evaporation from the ocean, which is greater when SSTs are high, is increasing in general, raising the risk of active hurricane seasons henceforth."
http://news.yahoo.com/s/space/20060...d2005hurricanes
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I anxiously await the response from the NOAA ... |
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| josh4 |
| quote: | Originally posted by occrider
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Wait so I'm confused, do you think the storms are a result of global warming or some naturally occurring weather pattern? I remember you posting something about the latter. |
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| Renegade |
I was actually just about to start this topic.
Here's the "Fox News" link I was about to post in case there was any fear of occrider's source being too "liberal":
http://www.foxnews.com/story/0,2933,200590,00.html
And from that:
| quote: | | Other new research Thursday showed that global warming produced about half of the extra hurricane-fueled warmth in the North Atlantic in 2005, and natural cycles were a minor factor, according to Kevin Trenberth and Dennis Shea of the National Center for Atmospheric Research, a research lab sponsored by the National Science Foundation and universities. |
And here is the report in its entirety:
http://fermat.nap.edu/catalog/11676.html
It's probably worth pointing out that this study was only commissioned because a Republican (Joe Barton) deigned to question the science behind global warming in the first place:
http://energycommerce.house.gov/108...232005_1570.htm
While I was once skeptical (though not dismissive) about anthropogenic global warming, I think it's now safe to say that the overwhelming weight of scientific evidence is now in its favour. I fail to see how the denial of AGW, given the current body of evidence to support it, is any more credible a position than the denial of the theory of evolution. The only question now, I suppose, is how to combat it?
EDIT:
On re-reading the articles, I think that we may actually be referencing two separate studies. Just to hammer the point home on my study (again from Fox News):
| quote: | WASHINGTON — It has been 2,000 years and possibly much longer since the Earth has run such a fever.
The National Academy of Sciences, reaching that conclusion in a broad review of scientific work requested by Congress, reported Thursday that the "recent warmth is unprecedented for at least the last 400 years and potentially the last several millennia."
A panel of top climate scientists told lawmakers that the Earth is heating up and that "human activities are responsible for much of the recent warming." |
I don't think there's any mention of hurricanes in the report I posted (it's 155 pages and I'm not about to trawl through all of it for a mention of hurricanes) but just chalk it up as another comprehensive study, conducted by another reputable scientific body, which suggests that the Earth is abnormally warm and that human activity is the major cause. Like I said, given the wealth of evidence in its favour, I'm just about ready to lump anthropogenic global warming up there with evolution as an undeniable tennet of science. |
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| Yoepus |
| Its disnomer, I read the otherday that the growing consensus among the science community is that global warmining, for the most part, is a natrual phenomena. |
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| Marc Summers |
| quote: | Originally posted by Yoepus
Its disnomer, I read the otherday that the growing consensus among the science community is that global warmining, for the most part, is a natrual phenomena. |
Except for 150+ years of spewing out greenhouse gasses and not to mention the O-zone munching CFC's acting as a catalist for global warming. |
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| occrider |
| quote: | Originally posted by Yoepus
Its disnomer, I read the otherday that the growing consensus among the science community is that global warmining, for the most part, is a natrual phenomena. |
Well actually my article demonstrates how the strong hurricane season is direcly related to global warming. The primary argument of the fox news article that renegade posted was that global warming is overwhelmingly caused by humans. What's the source for the statement that the "consensus" among scientists is that it's natural? |
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| Marc Summers |
| quote: | Originally posted by occrider
Well actually my article demonstrates how the strong hurrican season is direcly related to global warming. The primary argument of the fox news article that renegade posted was that global warming is overwhelmingly caused by humans. What's the source for statement that the "consensus" among scientists is that it's natural? |
Well, I'm going to agree with him, that it is natural. Scientists have been taking ice cores from the poles and have tested them for green house gasses. The deeper the core, the farther back in time. And they have mapped the amounts of gasses all the way to billions of years ago, and they have noticed a definate cycle of global warming. But we totally ed up that cycle with our idustrial ages, and lack of knowledge back in the beginning. |
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| JM |
apparently China is going to be adding more to Global Warming than the USA within a few years... I wonder if any attention from these blood sucking green losers will shift over to China...
>JM< |
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| occrider |
| quote: | Originally posted by JM
apparently China is going to be adding more to Global Warming than the USA within a few years... I wonder if any attention from these blood sucking green losers will shift over to China...
>JM< |
Well that's an excellent solution. We'll continue to be the worst polluters which will result in a situation where us, not China, will be the primary loser in the game of mother nature until we can get China to reduce their pollutants before us, the biggest polluter, does so. Fantastic. |
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| occrider |
| quote: | Originally posted by josh4
Wait so I'm confused, do you think the storms are a result of global warming or some naturally occurring weather pattern? I remember you posting something about the latter. |
Read the thread title please. |
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| josh4 |
| quote: | Originally posted by occrider
Read the thread title please. |
some PDDs will post pages of argument to avoid saying yes or no. |
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| occrider |
| quote: | Originally posted by josh4
some PDDs will post pages of argument to avoid saying yes or no. |
Huh? Is the thread title unclear as to what I think? |
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