Greenland update for 2010: record melting and a massive calving event

By: Dr. Jeff Masters , 2:31 PM GMT on March 04, 2011

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No humans were present on the morning of August 4, 2010, in a remote fjord in Northwest Greenland, when the air vibrated with a thunderous crack as one of the largest icebergs in world history calved from the Petermann Glacier, the island's second largest ocean-terminating glacier. Where the glacier meets the sea, a 43 mile-long tongue of floating ice existed at the beginning of 2010. On August 4 2010, a quarter of this 43 mile-long tongue of floating ice fractured off, spawning a 100 square mile ice island four times the size of Manhattan, with a thickness half that of the Empire State building. According to Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware's College of Earth, Ocean, and Environment, the freshwater stored in this ice island could have kept the Delaware or Hudson rivers flowing for more than two years, or kept all U.S. public tap water flowing for 120 days. There was speculation that the ice island could find its way into the open Atlantic Ocean in two years, and potentially pose a threat to oil platforms and ships. However, as the ice island made its turn to get from the narrow Petermann Fjord to enter Nares Strait between Greenland and Canada, the mighty iceberg split into thousands of small icebergs that will not pose an unusual threat to shipping when they emerge into the Atlantic.


Figure 1. The 100 square-mile ice island that broke off the Petermann Glacier heads out of the Petermann Fjord in this image taken by NASA's Aqua satellite on August 21, 2010. Image credit: NASA. I've constructed a 7-frame satellite animation available here that shows the calving and break-up of the Petermann Glacier ice island. The animation begins on August 5, 2010, and ends on September 21, with images spaced about 8 days apart. The images were taken by NASA's Aqua and Terra satellites.

Petermann Glacier spawned smaller ice islands in 2001 (34 square miles) and in 2008 (10 square miles). In 2005, the Ayles Ice Shelf, about 60 miles to the west of Petermann Glacier, disintegrated and became a 34 square-mile ice island. The August 2010 Petermann Glacier calving event created the largest iceberg observed in the Arctic since 1962, when the Ward Hunt Ice Shelf on the north coast of Canada's Ellesmere Island calved off a massive 230 square mile chunk. The Ward Hunt Ice Shelf also calved off a huge 21 square mile ice island a few days after the August 2010 Petermann Glacier calving event. According to an article in livescience.com, "Driftwood and narwhal remains found along the Ellesmere coast have radiocarbon dates from roughly 3,000 to 6,800 years ago, implying that the ice has been intact since those remains were deposited." All of the these calving events are evidence that the ice sheets in the Arctic are responding as one would expect to significantly warmer temperatures.

Warmer ocean temperatures cause significant melting of Greenland's glaciers
At a talk last December at the world's largest conference on climate change, the American Geophysical Union (AGU) meeting in San Francisco, glacier expert Eric Rignot of UC-Irvine implicated ocean warming as a key reason for the calving of the Petermann Glacier's ice island. The ocean waters near the glacier have warmed by 1 - 2°C over the past three years, he said, and all of the periphery of Greenland has seen ocean heat increases in recent years, with the result that 20 - 80% of all the mass lost by Greenland's glaciers in recent years could be attributed to melting of the glaciers by warmer waters attacking them from beneath. Ocean temperatures along the southwest coast of Greenland (60N to 70N, 60W to 50W) computed from the UK Hadley Center data set during 2010 were 2.9°C (5.2°F) above average--a truly remarkable anomaly, and far warmer than the previous record of 1.5°C above average set in 2003. Sea surface temperature records for Greenland began in the 1920s. A study earlier this year published in the journal Science (Spielhagen et al., 2011) found that ocean temperatures on the east side of Greenland are now at their warmest levels in at least 2,000 years. The researchers studied a sediment core containing fossil remains of planktic foraminifers, which vary as a function of water temperature. The study noted that not only have the waters flowing northward on the east side of Greenland warmed significantly, the volume of water flowing north has also increased, resulting in a large transport of heat into the Arctic. "Such an increased heat input has far-reaching consequences," they wrote.


Figure 2. Departure of sea surface temperature from average for 2010 from the NOAA Daily Optimum Interpolation SST Anomaly data set for October 2010. Areas colored red are warmer than the 1971-2000 average, areas colored blue are cooler than that average. A large region of record warm water temperatures extended along the west coast of Greenland, leading to record warm air temperatures and record melting along the western portion of Greenland in 2010. Ocean temperatures along the southwest coast of Greenland (60N to 70N, 60W to 50W) computed from the UK Hadley Center data set during 2010 were 2.9°C (5.2°F) above average--a truly remarkable anomaly, surpassing the previous record of 1.5°C set in 2003. Sea surface temperature records for Greenland began in the 1920s. Image credit: NOAA Visualization Lab.

Record warmth and melting in Greenland during 2010
Greenland's climate in 2010 was marked by record-setting high air temperatures, the greatest ice loss by melting since accurate records began in 1958, and the greatest mass loss of ocean-terminating glaciers on record. That was the conclusion of the 2010 Arctic Report Card, a collaborative effort between NOAA and European Arctic experts that comes out each year. Was 2010 the warmest year in Greenland's history? That is difficult to judge. We know it was also very warm in the late 1920s and 1930s in Greenland, but we only have two stations, Godtahab Nuuk and Angmagssalik, with weather records that go back that far (Figure 3.) Godtahab Nuuk set a record high in 2010, but temperatures at Angmagssalik in 2010 were similar to what was observed during several years in the 1920s and 1930s. Marco Tedesco of the City College of New York's Cryosphere Processes Laboratory remarked that last year's record warmth and melting in Greenland began when an unusually early spring warm spell reduced and "aged" the snow on the surface of the ice sheet, so that the snow became less reflective, allowing it to absorb more heat from the sun. This accelerated snow melt even further, exposing the bare ice, which is less reflective than snow and absorbs more heat. This feedback loop extended Greenland's record melting season well into the fall.


Figure 3. Historic temperatures in Greenland for the six stations with at least 50 years of data, as archived by NASA. Three of the six stations set record highs in 2010. However, only two of the six stations (Godtahab Nuuk and Angmagssalik) have data going back beyond the 1930s, which was a period of warmth in Greenland similar to the warmth of the current decade. Godtahab Nuuk set a record high in 2010, but 2003 still ranks as Angmagssalik's hottest year on record.


Figure 4. The 2010 summer melt season was lasted more than 40 days longer (purple colors) than the mean melt season from 1979 - 2007. Image credit: Arctic Report Card.

Why Greenland matters: sea level rise
The major concern with a warming climate in Greenland is melting of the Greenland ice sheet, which currently contributes about 25% of the observed 3 mm/year (1.2 inches per decade) global rise in sea level. Higher sea levels mean increased storm surge inundation, coastal erosion, loss of low-lying land areas, and salt water contamination of underground drinking water supplies. Greenland ice mass loss is accelerating over the long term, according to independent estimates using three different techniques (Figure 5), with more mass being lost each year than the previous year. According to Rignot et al., 2011, ice mass loss is also accelerating in Antarctica, and "the magnitude of the acceleration suggests that ice sheets will be the dominant contributors to sea level rise in forthcoming decades, and will likely exceed the IPCC projections for the contribution of ice sheets to sea level rise in the 21st century." As I discussed in a 2009 blog post, How much will global sea level rise this century?, the IPCC in 2007 estimated that global sea level would rise 0.6 - 1.9 feet by 2100, but several studies since then predict a higher range of 1.6 - 6.6 feet.

During the warm period 125,000 years ago, before the most recent ice age, roughly half of the Greenland ice sheet melted. This melting plus the melting of other smaller Arctic ice fields is thought to have caused 7.2 - 11.2 feet (2.2 - 3.4 meters) of the 13 - 20 foot (4 - 6 meter) sea level rise observed during that period. Temperatures in Greenland are predicted to rise 3°C by 2100, to levels similar to 125,000 years ago. If this level of warming occurs, we can expect sea levels to rise 13 - 20 feet several centuries from now. There's enough water locked away in the ice sheet to raise sea level to rise 23 feet (7 meters), should the entire Greenland ice sheet melt.


Figure 5. Loss of mass from Greenland's ice sheet in gigatons per year from 1992 through 2009, as computed from satellite gravity measurements from the GRACE satellites (red line) and from a mass balance method. The mass balance method computes the amount of snow on the surface, the amount of ice mass lost to wind and melt, and the amount of ice lost computed from glacier velocity and ice thickness. Adding together these terms gives the total amount of ice lost or gained over the ice sheet. The acceleration is given in gigatons per year squared. Another paper by Zwally et al. (2011) used a third method, laser satellite altimetry, to determine Greenland mass loss. Between 2003 to 2007, the ice sheet lost 171 gigatons of mass per year. Between 1992 to 2002, Greenland was only losing only 7 gigatons per year. Image credit: Rignot et al., 2011, Geophysical Research Letters.

References
Rignot, E., et al., 2011: Acceleration of the contribution of the Greenland and Antarctic Ice Sheets to sea level rise, Geophysical Research Letters, in press, doi:10.1029/2011GL046583.

Spielhagen, et al., 2011, Enhanced Modern Heat Transfer to the Arctic by Warm Atlantic Water, Science 28 January 2011: Vol. 331 no. 6016 pp. 450-453 DOI: 10.1126/science.1197397

Zwally, J., et al., 2011, Greenland ice sheet mass balance: distribution of increased mass loss with climate warming; 2003 - 07 versus 19922 - 2002, Journal of Glaciology, Vol. 57, No. 201, 2011.

Wunderground's climate change section has a Greenland web page with detailed information and references.

Jeff Masters

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Hi all. I have just been looking through the past 13days of Dr. Masters Blogs. Not one mention of the $20billion quake in Christchurch. Also, this piece of ice broke off on August 8, 2010, not in Jan or Feb 2011, it's summer in Greenland then. BTW how did Greenland get it's name???? Maybe it was "green" many 100's or 1000's of years ago. If this event had of happened in Iceland then I would be more worried.
Any mention of the Tornado that killed a young mother and left 40houses uninhabitable and another 60 possibly the same.
Also, what's going on off the coast of Oregon, 3 quakes at not much depth, 4.6, 4.8 and 4.9. slow release of energy I hope.
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Quoting DontAnnoyMe:
Haven't seen this hazards map so loaded lately.





oh great...not to mention the silly string map'o'death

g'nite my friends
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Haven't seen this hazards map so loaded lately.



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Quoting aquak9:
concerned, frightened, worried, losing sleep- rabid lazy homeless squirrels looking for handouts, wearing expensive shoes

I think I'm going nuts


Well, that would explain the picture you posted. That was pure excitement.

"MY GAWD, would you look at the size of that NUT!!!!!!!"
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Quoting aquak9:
concerned, frightened, worried, losing sleep- rabid lazy homeless squirrels looking for handouts, wearing expensive shoes

I think I'm going nuts
very silly
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concerned, frightened, worried, losing sleep- rabid lazy homeless squirrels looking for handouts, wearing expensive shoes

I think I'm going nuts
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Quoting washingtonian115:
Yeahhhhhhh to a more interesting topic(if it even matters)a scientist says he found evidence that their is alien life......huh why won't these people give up on trying to find life?

I heard it was false, but in any matter, what is wrong with trying to find extraterrestrial life?
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Quoting aquak9:
Pcola- it depends, if he was selling something, then yes you should be worried.


No, had one of those - "Homeless veteran, anything will help. God bless" signs. The two $150 pairs of shoes was a dead give away though. Sent it on it's way. Might have fallen for it if it had a cute dog on a leash though. ;)
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Yeahhhhhhh to a more interesting topic(if it even matters)a scientist says he found evidence that their is alien life......huh why won't these people give up on trying to find life?
Member Since: August 14, 2010 Posts: 10 Comments: 17475
Quoting TomTaylor:


Debatable things:
The effects of a warmer climate are obviously debatable.

The amount humans are contributing is obviously debatable. However, that will likely never be answerable. (By answerable, I also mean 100% accurate)

Whether or not we will be warmer in the future and how much warmer we will be in the future is debatable, because we can't say for certain we will be warmer in the future.




Not debatable things:
Whether or not we have warmed, is not debatable. Everything indicates warming, the only discrepancy is how much we've warmed.

Whether or not humans are contribute to the temperature of our planet is not debatable.

Whether or not humans are contributing to the change in the temperature of our planet is not debatable. (Note, the amount we are contributing is debatable)





Did I miss anything?


Does anybody disagree with this? Skeptics and Deniers, any input?

If not then we should no longer be debating whether or not humans are contributing to the warming, and we should not be debating if we have been warming.

The only things to debate (assuming everyone agrees with the quote above) are the effects of a warmer planet, the amount humans are responsible for this warming trend, and whether or not we will be warmer in the future.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
878. BtnTx
Geez, watching NASA TV I think what I thought just happened I think happened 6 hours ago! Oh well...
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Quoting aquak9:
icebergs melting, greenhouse gasses, volcanoes, earthquakes...

and now I gotta worry about the damn squirrels, too?


Looks like he has rabies...I'd be concerned
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Pcola- it depends, if he was selling something, then yes you should be worried.
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875. BtnTx
NASA crews are saying goodbye now on NASA TV
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868 the undebatables yes, not to mention uncertainty everywhere yet strangely lacking in hurricane intensity and incidence. That is somehow clearly decreasing in line with consensus.
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873. BtnTx
NASA STS133 Farewell ceremony is<30+ minutes away
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Quoting aquak9:
icebergs melting, greenhouse gasses, volcanoes, earthquakes...

and now I gotta worry about the damn squirrels, too?



Actually had one come knock on our patio door this afternoon. :O
Should I be frightened?
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867. Neapolitan 9:06 PM EST on March 06, 2011

You are dealing with convolution of your multitudes of negative and attacking responses to posts. Perhaps if you did not carry such a big chip on your shoulder and not demean and taunt others regularly, you would be more likable. I don't see that happening however. :( Pffft!

Member Since: June 12, 2005 Posts: 6 Comments: 8186
icebergs melting, greenhouse gasses, volcanoes, earthquakes...

and now I gotta worry about the damn squirrels, too?

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Quoting Grothar:



Levi, you are beginning to sound like me with your responses. That's not nice. LOL


You're right! One of you is enough. ;)

Oh, Hi Gro.
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Quoting Levi32:


I'm pretty sure changes in gas concentrations changes the radioactive feedbacks in the atmosphere. The debate is whether we really know exactly how. So far, 20th century warming has not exceeded normal holocene interglacial variation (discussed here).

I'm pretty sure I can also say with confidence that squirrel population has an effect on the Earth's temperature.

So what exactly remains to be debated regarding the "AGW theory"? Please correct me where you think I am wrong...



Debatable things:
The effects of a warmer climate are obviously debatable. (Though from the looks of it, you have a great grasp on the changes spawned by a warmer planet)

The amount humans are contributing is obviously debatable. However, that will likely never be answerable. (By answerable, I also mean 100% accurate)

Whether or not we will be warmer in the future and how much warmer we will be in the future is debatable, because we can't say for certain we will be warmer in the future.




Not debatable things:
Whether or not we have warmed, is not debatable. Everything indicates warming, the only discrepancy is how much we've warmed.

Whether or not humans are contribute to the temperature of our planet is not debatable.

Whether or not humans are contributing to the change in the temperature of our planet is not debatable. (Note, the amount we are contributing is debatable)





Did I miss anything?





Did I miss anything?
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Quoting Ossqss:


So let's see,,,, you completely avoid the obvious questionable nature of what you boasted as undeniably quality stuff, and attacked everything and everyone around the subject, but no response to the question on the subject legitimacy or documented history. That is very reminiscent of some other posters here. How does that make you feel, good, great, or guilty again ? Think about it......

Ummm...what? If you feel the need to snipe, would you be so kind as to be specific? Or are you just unhappy with me calling you out earlier? (I'm gonna go with 'B'). To rehash, 1) I posted a link to an article that just yesterday hit the news, and tomorrow is being opened for commentary by all comers. 2) Out of what I can only assume is a burning need to score points off of me, you responded with "Recycled news", and a linkg to a seven-year old snippet where the discovery was announced in brief. 3) I responded by outlining the clear difference between that to which I'd linked, and that to which you'd linked. 4) You responded by linking to a ridiculous but expected snide remark from the anti-science site WUWT that basically thrashed Fox News more than it did the original article to which I'd linked. 5) I called you out on that, and 6) now you respond by accusing me of "completely avoiding the obvious questionable nature of what you boasted as undeniably quality stuff".

Right...

I have to say, with your frequent and increasingly bizarre accusations of wrongdoing on my part--am I a pseudonym? Where do I live? How much does Dr. Masters pay me to post?--I've come to the conclusion that you've developed an unhealthy fascination with me. For the good of the blog, I'm going to make you the sole occupant of my ignore list, and respectfully beg you on bended knee to do the same with me. Thanks.

Edited to add: note that I never said the article was correct, or would be proven as such; I merely stated that if it were proven true, it would be one of the most monumental scientific discoveries of all time. I still stand by that.
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Quoting JFLORIDA:
Both vortexes are not behaving the same. And even the northern one has shifted and is behaving erratically. None of this was set in stone and SSTs have decidedly increased, and they are the "fuel" for cyclones.

WUWT is tripping over itself now to quote a 10 year old science on snowstorms that followed the same line of reasoning really. That the continuous gradient would diminish with warming and decrease snow events.


Well no. Polar amplification could mean more negative AO-type modes which shift the greatest gradient farther south, increasing baroclinic snowstorms, before the entire system was overwhelmed and snow decreased everywhere.

But....IPCC models project a strengthening of the arctic vortex, and thus a more positive AO with time. An interesting note is that it is currently disobeying that trend for the last 20 years.

As far as erratic behavior, I don't know what you mean, but we are far from fully understanding how the polar annular modes work.
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Member Since: July 3, 2005 Posts: 426 Comments: 129089
Both vortexes are not behaving the same. And even the northern one has shifted and is behaving erratically. None of this was set in stone and SSTs have decidedly increased, and they are the "fuel" for cyclones.

WUWT is tripping over itself now to quote a 10 year old science on snowstorms that followed the same line of reasoning really. That the continuous gradient would diminish with warming and decrease snow events.
Member Since: May 22, 2006 Posts: 188 Comments: 24743
Quoting Levi32:


I'm pretty sure changes in gas concentrations changes the radioactive feedbacks in the atmosphere. The debate is whether we really know exactly how. So far, 20th century warming has not exceeded normal holocene interglacial variation (discussed here).

I'm pretty sure I can also say with confidence that squirrel population has an effect on the Earth's temperature.

Interesting point. If trends continue, however...

And squirrels, do indeed have an effect.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Hummm, perusing some filed items. Page 739 is interesting on this.....

Link

So nobody wants to shred this item I placed up for sacrifice the other day with respect to contribution to the warming ? C'mon, its easy math stuff, no?

Just how much of the "Greenhouse Effect" is caused by human activity?

Member Since: June 12, 2005 Posts: 6 Comments: 8186
Quoting JFLORIDA:
Still levi with recent arctic trends like the dipole and the antarctic circumpolar vortex things don't seem to be following an ideal case.

Im not just truing to be contrary here; i don't see ideal hadley circulation at all. And even so wouldn't it shift anyway into the polar circulation areas more, and with the potential for new patterns like the arctic dipole couldn't that gradient theoretically increase.


Polar vortexes are driven by the temperature gradient. That's why the jetstream exists. Reduce the gradient and you weaken the vortex. That's exactly what happens in the summer hemisphere when the polar region warms up a whole lot relative to the equator.
Member Since: November 24, 2005 Posts: 635 Comments: 26682
Quoting TomTaylor:


Good.


Great explanation, that makes perfect sense.


Wait a minute? What is there to debate? As long as there is 1 human being on this planet he or she has an input on the temperature. Insignificant? Absolutely. Let's try 6.8 billion, maybe that will have a grander effect.

As far as I am aware, there is no debate that humans do or don't contribute to the temperature of our planet. Because they obviously do.

The only debatable topic is, is our planet warming. That's a tough question because to say it is warming now means you know it will be warmer in the future. It has been warming. And likely will continue.


Another debatable thing is how responsible humans are for the current warming. Assuming none of the natural variables are changing, we'd be 100% responsible. That isn't likely to be the case, but solar input really hasn't changed, so it is likely mostly human happening.

One last thing up for debate is the effect a warmer climate posses on weather events such as hurricanes, snow storms, etc.


But once again, there is no debate on whether or not humans are contributing to the warmth, everything in Earth's system plays some role, no matter how small, on Earth's temperature.


I'm pretty sure changes in gas concentrations changes the radioactive feedbacks in the atmosphere. The debate is whether we really know exactly how. So far, 20th century warming has not exceeded normal holocene interglacial variation (discussed here).

I'm pretty sure I can also say with confidence that squirrel population has an effect on the Earth's temperature.
Member Since: November 24, 2005 Posts: 635 Comments: 26682
Quoting Levi32:


Ok, that wasn't very hard right. Thanks. I will not bother asking for data, but I will just point out that it is only the Atlantic, which has been on the uptick in the AMO since the mid-1980s.

he's got a point...the concept of global warming is global
Quoting Levi32:

Yeah, the Earth is warming, energy is released from ice. It kind of proves nothing. It is the cause that is debated, not the weather that is happening around us.

More specifically, the percent of cause.

Causes for warming have already been defined (maybe not all of them), humans being one of them.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
Quoting Levi32:


Lol, nice avoidance. Get off the blog then and study. Your calculations still don't exist until you show them. You can do that another time, although none of us will remember to ask you.

It also requires no account to upload on tinypic and takes a few seconds to upload something. No pressure.



Levi, you are beginning to sound like me with your responses. That's not nice. LOL
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Thanks sun for the full PDF. Reading it.


Observed poleward expansion of the Hadley circulation since 1979

Using three meteorological reanalyses and three outgoing long-wave radiation (OLR)
datasets, we show that the Hadley circulation has a significant poleward expansion of
about 2 to 4.5 degrees of latitude since 1979.
Member Since: May 22, 2006 Posts: 188 Comments: 24743
On the changes in number and intensity of North Atlantic tropical cyclones Authors: William M. Briggs (Submitted on 31 Jan 2007)

Abstract: Bayesian statistical models were developed for the number of tropical cyclones and the rate at which these cyclones became hurricanes in the North Atlantic. We find that, controlling for the cold tongue index and the North Atlantic oscillation index, there is high probability that the number of cyclones has increased in the past thirty years; but the rate at which these storms become hurricanes appears to be constant. We also investigate storm intensity by measuring the distribution of individual storm lifetime in days, storm track length, and Emanuel's power dissiptation index. We find little evidence that the distribution of individual storm intensity is changing through time. Any increase in cumulative yearly storm intensity and potential destructiveness, therefore, is due to the increasing number of storms and not due to any increase in the intensity of individual storms.


PDF Link
Member Since: August 2, 2010 Posts: 21 Comments: 9874
Quoting bappit:

Somebody pressed Levi's on button.


Good.
Quoting Levi32:


Explain "more widespread variances." The greenhouse effect reduces temperature variance within the Earth system.

And no, tropical cyclones should not necessarily be getting stronger and longer-lasting. While they have more fuel available, the need for them is less. The temperature imbalance of the Earth has been decreasing during the last 30 years as it has warmed, which is the natural course of things. This also reduces extreme weather in general (less baroclinicity).



^Northern hemisphere only^


Great explanation, that makes perfect sense.

Quoting Levi32:


No. Don't give me the scientific law speech. Until there is no debate, it's not proven. You don't see people still arguing over whether gravity exists.



Wait a minute? What is there to debate? As long as there is 1 human being on this planet he or she has an input on the temperature. Insignificant? Absolutely. Let's try 6.8 billion, maybe that will have a grander effect.

As far as I am aware, there is no debate that humans do or don't contribute to the temperature of our planet. Because they obviously do.

The only debatable topic is, is our planet warming. That's a tough question because to say it is warming now means you know it will be warmer in the future. It has been warming. And likely will continue.


Another debatable thing is how responsible humans are for the current warming. Assuming none of the natural variables are changing, we'd be 100% responsible. That isn't likely to be the case, but solar input really hasn't changed, so it is likely mostly human happening.

One last thing up for debate is the effect a warmer climate posses on weather events such as hurricanes, snow storms, etc.


But once again, there is no debate on whether or not humans are contributing to the warmth, everything in Earth's system plays some role, no matter how small, on Earth's temperature.
Member Since: August 24, 2010 Posts: 19 Comments: 4358
So we get more tropical non-frontal systems and have fewer baroclinic systems with fronts.


Quoting Levi32:


Well wouldn't it be if there was a suppression effect in place?

Why would ACE increase if there was a suppression effect.

Ive haven't seen a hurricane go to the arctic and poop out because it was too warm up there yet.

We're talking global here. The Hadley circulation is slowed when it is not as cold to the north. The only reason air rises at the equator (and thus forms tropical cyclones) is because it is warm there relative to everywhere else.
Member Since: January 25, 2011 Posts: 0 Comments: 173
Quoting alfabob:


First AGW is not a theory, it has already been proven. If you can prove to me that all regions on the Earth combined have not been increasing in thermal energy then I'll retract that statement. But I've already done the calculations, and there is a consistent overall increase which is about equivalent to all the heat emitted from the surface of the Earth.

Second, the heat will always be stronger near the surface of the Earth. Greenhouse gases would be most concentrated in the lower atmosphere, so in order to release the energy; convection must occur to propel the moisture above this layer where it can then freely radiate out to space. I've also analyzed hurricane seasons from 1930-2010 and the yearly occurrence of the higher wind speeds have been increasing. If anything the accelerated melting of the pole should be inhibiting the development of hurricanes due to increased shear. But we all know that is not an unlimited resource and increased SST means increased activity.


Scientifically speaking, pretty much everything that has reviewed solid evidence is a theory. Some theories are so solid that they're practically unchallengeable, however they are still theories. Math gets proven, science gets evidence. Theories without evidence are just hypotheses.

Global warming is a real observable fact. The temperatures have been rising both across surface and satellite measurements. But global warming isn't a theory, it is an observation.

AGW is a theory proposed to explain the observation of rising temperatures. It is well supported, with plenty of research to back it up. There is a high level of confidence that humans are either a major proponent or the sole proponent in causing the globe to warm.

Is the theory on solid ground? Yes. Has it made useful predictions? Yes. Is it "proven"? No. It's currently the best explanation we have that fits the observations, but even now new discoveries are being made and new research is being done to better hone it and improve it. New theories are being added, others are being modified, and still others are being thrown out. It's an area of active research.

The real question when it comes to science is whether there is enough evidence to act on the predictions made by a theory. In the case of AGW, according to our best science on the subject, the answer is yes.

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Levi is in rare form.
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Still levi with recent arctic trends like the dipole and the antarctic circumpolar vortex things don't seem to be following an ideal case.

Im not just truing to be contrary here; i don't see ideal hadley circulation at all. And even so wouldn't it shift anyway into the polar circulation areas more, and with the potential for new patterns like the arctic dipole couldn't that gradient theoretically increase.
Member Since: May 22, 2006 Posts: 188 Comments: 24743
Near albany. Heavy sleet mixing with snow here!
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I guess we need to qualify possible climate induced cyclone "suppression" effects.

So far I remember

the SAL.
surface pressure trend
MJO.
general shear
ENSO.
Member Since: May 22, 2006 Posts: 188 Comments: 24743
000
WEHW42 PHEB 070022
TIBHWX
HIZ001>003-005>009-012>014-016>021-023>026-070222 -
TSUNAMI INFORMATION STATEMENT NUMBER 1
NWS PACIFIC TSUNAMI WARNING CENTER EWA BEACH HI
222 PM HST SUN MAR 06 2011
TO - CIVIL DEFENSE IN THE STATE OF HAWAII
SUBJECT - TSUNAMI INFORMATION STATEMENT
THIS STATEMENT IS FOR INFORMATION ONLY. NO ACTION REQUIRED.
AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS
ORIGIN TIME - 0210 PM HST 06 MAR 2011
COORDINATES - 10.3 SOUTH 160.9 EAST
LOCATION - SOLOMON ISLANDS
MAGNITUDE - 6.6 MOMENT
EVALUATION
BASED ON ALL AVAILABLE DATA A DESTRUCTIVE PACIFIC-WIDE TSUNAMI IS
NOT EXPECTED AND THERE IS NO TSUNAMI THREAT TO HAWAII. REPEAT. A
DESTRUCTIVE PACIFIC-WIDE TSUNAMI IS NOT EXPECTED AND THERE IS NO
TSUNAMI THREAT TO HAWAII.
THIS WILL BE THE ONLY STATEMENT ISSUED FOR THIS EVENT UNLESS
ADDITIONAL DATA ARE RECEIVED.


Member Since: Posts: Comments:
Quoting JFLORIDA:


Well wouldn't it be if there was a suppression effect in place? I dont know, you guys are always talking about it. Also I dont get the ACE and pole energy value if the water surface and atmosphere gradient has also increased.

Im old and forgetful and we may have talked about this already but,

Ive haven't seen a hurricane go to the arctic and poop out because it was too warm up there yet. So I assume you are talking about blocking descending air causing an overall increase in surface pressure. I wouldn't think things would occur so generally.

Accumulated cyclone energy (ACE) is a measure used by the National Oceanic and Atmospheric Administration (NOAA) to express the activity of individual tropical cyclones and entire tropical cyclone seasons, particularly the North Atlantic hurricane season. It uses an approximation of the energy used by a tropical system over its lifetime and is calculated every six-hour period. The ACE of a season is the sum of the ACEs for each storm and takes into account the number, strength, and duration of all the tropical storms in the season


Well wouldn't it be if there was a suppression effect in place?

Why would ACE increase if there was a suppression effect.

Ive haven't seen a hurricane go to the arctic and poop out because it was too warm up there yet.

We're talking global here. The Hadley circulation is slowed when it is not as cold to the north. The only reason air rises at the equator (and thus forms tropical cyclones) is because it is warm there relative to everywhere else.
Member Since: November 24, 2005 Posts: 635 Comments: 26682
Quoting Xyrus2000:


Opposite of what is true? Both Levi and I were agreeing. Warmer global temperatures would ultimately result in fewer storms, but those storms would be stronger.

My only quibble was that it would seem that the warmer temps through the troposphere in the tropics would have more to do with with hurricane formation than the gradient between the arctic and the tropics (of course, that is important too). However, I'm not an expert on hurricane formation, hence the speculation on the cause.


Well, I think you both agree with the data and studies presented here...
Member Since: August 2, 2010 Posts: 21 Comments: 9874
Quoting Levi32:


Oh. What...the increase is hidden? I think ACE data speaks pretty clear for itself.





Well wouldn't it be if there was a suppression effect in place? I dont know, you guys are always talking about it. Also I dont get the ACE and pole energy value if the water surface and atmosphere gradient has also increased.

Im old and forgetful and we may have talked about this already but,

Ive haven't seen a hurricane go to the arctic and poop out because it was too warm up there yet. So I assume you are talking about blocking descending air causing an overall increase in surface pressure. I wouldn't think things would occur so generally.

Accumulated cyclone energy (ACE) is a measure used by the National Oceanic and Atmospheric Administration (NOAA) to express the activity of individual tropical cyclones and entire tropical cyclone seasons, particularly the North Atlantic hurricane season. It uses an approximation of the energy used by a tropical system over its lifetime and is calculated every six-hour period. The ACE of a season is the sum of the ACEs for each storm and takes into account the number, strength, and duration of all the tropical storms in the season
Member Since: May 22, 2006 Posts: 188 Comments: 24743
Quoting Xyrus2000:


Opposite of what is true? Both Levi and I were agreeing. Warmer global temperatures would ultimately result in fewer storms, but those storms would be stronger.

My only quibble was that it would seem that the warmer temps through the troposphere in the tropics would have more to do with with hurricane formation than the gradient between the arctic and the tropics (of course, that is important too). However, I'm not an expert on hurricane formation, hence the speculation on the cause.


Horizontal temperature gradients matter because without them the atmosphere would not undergo large-scale vertical overturning in cells, which it does, precisely because the equator is warmest.
Member Since: November 24, 2005 Posts: 635 Comments: 26682
A Universal Hurricane Frequency Function
Authors: Robert Ehrlich (Submitted on 17 Feb 2010)

Abstract: Evidence is provided that the global distribution of tropical hurricanes is principally determined by a universal function H of a single variable z that in turn is expressible in terms of the local sea surface temperature and latitude. The data-driven model presented here carries stark implications for the large increased numbers of hurricanes which it predicts for a warmer world. Moreover, the rise in recent decades in the numbers of hurricanes in the Atlantic, but not the Pacific basin, is shown to have a simple explanation in terms of the specific form of H(z), which yields larger percentage increases when a fixed increase in sea surface temperature occurs at higher latitudes and lower temperatures.

Link
Member Since: August 2, 2010 Posts: 21 Comments: 9874
Member Since: Posts: Comments:
Quoting alfabob:
This is only the energy from worldwide ice melting (Data from WGI, PIOMAS, and GRACE. I used 2 papers for calculating how much energy the ocean is absorbing, but since we can't measure it perfectly it has more error. Either way it makes the melting of ice seem like nothing in comparison. Back to studying, just trying to make you realize that AWG is real and not just a bunch of bored scientist trying to get attention.


Yeah, the Earth is warming, energy is released from ice. It kind of proves nothing. It is the cause that is debated, not the weather that is happening around us.
Member Since: November 24, 2005 Posts: 635 Comments: 26682
This is only the energy from worldwide ice melting (Data from WGI, PIOMAS, and GRACE. I used 2 papers for calculating how much energy the ocean is absorbing, but since we can't measure it perfectly it has more error. Either way it makes the melting of ice seem like nothing in comparison. Back to studying, just trying to make you realize that AWG is real and not just a bunch of bored scientist trying to get attention.

Member Since: Posts: Comments:
Quoting sunlinepr:


Numerous studies in recent years have found no evidence that the number of hurricanes and their northwest Pacific Ocean cousins, typhoons, is increasing because of the rise in global temperatures.

But a new study in the journal Nature found that hurricanes and typhoons have become stronger and longer-lasting over the past 30 years. These upswings correlate with a rise in sea surface temperatures.

The duration and strength of hurricanes have increased by about 50 percent over the last three decades, according to study author Kerry Emanuel, a professor of atmospheric science at the Massachusetts Institute of Technology in Cambridge.
Emanuel's finding defies existing models for measuring storm strength. Current models suggest that the intensity of hurricanes and typhoons should increase by 5 percent for every 1�C (1.8�F) rise in sea surface temperature


Link

AND

The latest understanding of hurricanes is that almost the opposite is true: storms may actually decline in frequency as the planet warms, even as they grow in strength.

Link


Opposite of what is true? Both Levi and I were agreeing. Warmer global temperatures would ultimately result in fewer storms, but those storms would be stronger.

My only quibble was that it would seem that the warmer temps through the troposphere in the tropics would have more to do with with hurricane formation than the gradient between the arctic and the tropics (of course, that is important too). However, I'm not an expert on hurricane formation, hence the speculation on the cause.
Member Since: October 31, 2009 Posts: 0 Comments: 1552

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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.

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