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Global warming may not be the culprit after all when it comes to Artic changes

Climate data can be difficult to analyze. Take for instance global temperature changes. Whereas the Northern Hemisphere has been warming, the Southern half of the planet is cooling. While Antarctic Ice is at near-record levels, the Northern Pole is warming at an unprecedented pace-- much faster than global warming models predict.

A new study published in the journal Nature identified a possible cause for this discrepancy. It identifies a natural, cyclical flow of atmospheric energy around the Arctic Circle. A team of researchers, led by Rune Graversen of Stockholm University, conclude this energy flow may be responsible for the majority of recent Arctic warming.

The study specifically rules out global warming or albedo changes from snow and ice loss as the cause, due to the "vertical structure" of the warming ... the observed warming has been much too weak near the ground, and too high in the stratosphere and upper troposphere.

This study follows hot on the heels of research by NASA, which identified "unusual winds" for rapid Arctic ice retreat. The wind patterns, set up by atmospheric conditions from the Arctic Oscillation, began rapidly pushing ice into the Transpolar Drift Stream, a current which quickly sped the ice into warmer waters.

A second NASA team, using data from the the GRACE (Gravity Recovery and Climate Experiment) satellite, recently concluded that changes in the Arctic Oscillation were "mostly decadal in nature", rather than driven by global warming.



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RE: Wrong again Masher
By masher2 (blog) on 1/3/2008 6:52:45 PM , Rating: 5
Good post Rove. However, the evidence for Southern Hemisphere cooling is more than accumulating snow (which you mention) and increasing sea ice (which you don't, and which isn't explained by AGW theory). The latest NOAA satellite date shows no temperature increase for the SH for the past 25 years, and a net decline in temperature over the past 10.

http://www.atmos.uah.edu/data/msu/t2lt/

While 25 years may seem like a short period, its important to remember that, for most of the SH, we lack high-quality data for further back than this.

Several other papers have demonstrated a net cooling in Antarctica going back to at least 1986, such as:

http://www.nature.com/nature/journal/v415/n6871/ab...

Dr. Madhav Khandekhar, an IPCC expert reviewer with whom I correspond with on a regular basis, sums it up well:
quote:
In the Southern Hemisphere, the land-area mean temperature has slowly but surely declined in the last few years. The city of Buenos Aires in Argentina received several centimetres of snowfall in early July, and the last time it snowed in Buenos Aires was in 1918! Most of Australia experienced one of its coldest months of June this year. Several other locations in the Southern Hemisphere have experienced lower temperatures in the last few years. Further, the SSTs (sea surface temperatures) over world oceans are slowly declining since mid-1998, according to a recent world-wide analysis of ocean surface temperatures
http://www.thehilltimes.ca/html/cover_index.php?di...


RE: Wrong again Masher
By smitty3268 on 1/3/2008 7:20:01 PM , Rating: 2
Didn't you post something about this earlier, and although the study said it was actually cooling slightly the margin of error was large enough that it could have actually been warming?


RE: Wrong again Masher
By masher2 (blog) on 1/4/2008 12:25:51 PM , Rating: 2
I think you're referring to this study:

http://journals.royalsociety.org/content/38315t224...

which found an increasing trend in Antarctic snow/ice mass, though the increase was within the margin of error.

Sea ice is a more accurate proxy for surface temperatures, however, as snow levels can increase or decrease regardless of temperature. And Antarctic sea ice is definitely on an increasing trend.


RE: Wrong again Masher
By AlexWade on 1/4/2008 1:12:39 PM , Rating: 3
To prove the ANTarctic is gaining ice, see these links:
http://arctic.atmos.uiuc.edu/cryosphere/
More specifically, this chart:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/cur...

The antarctic sea ice is about 2 million square KM above normal for this time of the year. Remember, this is their summer.


RE: Wrong again Masher
By Rovemelt on 1/5/08, Rating: 0
RE: Wrong again Masher
By masher2 (blog) on 1/5/2008 1:06:30 PM , Rating: 3
> "Masher, that publication you're referencing is over 10 years old."

Eh? It was published July 2006. Also the UAH NOAA data (as well as the cryosphere data posted by AW) is current as of 2007. The *oldest* study I cited was published in 2002, and it examined the cooling trend in Antarctica from 1986-2000.

Furthermore, the study you cite refers to mass balance only, and isn't even a study of Antarctic (much less SH) temperatures at all. As you yourself have pointed out many times, there isn't a direct relationship between the two. Cooling temperatures can (and often do) imply less snowfall.

Sea ice, however, is directly coupled to temperature. And sea ice is unequivocally increasing.


RE: Wrong again Masher
By Rovemelt on 1/5/2008 1:27:16 PM , Rating: 3
You're right, I misread it as 1996...it says 2006.


RE: Wrong again Masher
By Rovemelt on 1/5/08, Rating: 0
RE: Wrong again Masher
By masher2 (blog) on 1/5/2008 12:26:59 PM , Rating: 4
That's because you've misinterpreted the studies. First of all, this study, along with the followon from NASA specifically excludes global warming from being the cause of this heat transport mechanism:
quote:
Our study confirms many changes seen in upper Arctic Ocean circulation in the 1990s were mostly decadal in nature, rather than trends caused by global warming, " said Morison.
Second of all, global warming does not imply anthropogenic global warming. Most scientists believe in global warming. The debate is over the cause and extent of that warming.

> "Dr. Madhav Khandekhar has already clearly made up his mind with regards to whose agenda he supports. "

We're well aware that you consider each and every one of the hundreds of scientists who consider AGW incorrect to be paid off stooges, but it really doesn't work like that. The fact remains that, for any scientist seeking research funds, the financial incentive to support AGW is a thousand times larger than to deny it. For EU funded research, now, its a hard-and-fast requirement that any funding request be for research that least implicitly acknowledges AGW.


RE: Wrong again Masher
By Rovemelt on 1/5/2008 1:23:42 PM , Rating: 2
Yes, the author does support anthropogenic global warming theory and does so implicitly.

Maybe you should read what the author (Rune G. Graversen) had to say in an interview(s) regarding his publication:

http://environment.newscientist.com/article/dn1313...

quote:
The researchers found that most of the warming is happening high above ground. At midsummer, the data shows that the air that has warmed the most is 2 kilometres above land.

This, says Graversen, rules out the theory that Arctic warming is being accelerated by melting ice. Although the researchers remain unsure what is accelerating Arctic warming, they suggest it might be related to how fast energy is being transported towards the North Pole by cyclones.

The team calculated the flow of energy into the Arctic Circle using meteorological data, and looked at how this flow has changed since the 1980s.

They found that the amount of energy transported from the tropics into the Arctic has increased and that the increase corresponds to the rise of temperatures in the region.

"We are not saying this is the only explanation," says Graversen, "this could explain maybe 25% of the amplification of warming in the Arctic."


And here, where the lead author states quite clearly:

http://news.nationalgeographic.com/news/2008/01/08...

quote:
"This assumption is that if this [heat flow] has increased—which we see in the data that it has—then it has contributed to the warming in the Arctic, not only at the surface, but higher in the atmosphere," Graversen said.

Increased moisture in northward-moving air also plays a role, he said, because when the water vapor condenses into clouds and snow, it releases energy, warming the air.

Nobody knows how much of this change is the result of human emissions of planet-warming gases such as carbon dioxide, but it's likely that they play a role.

"Many models suggest an increase in energy transport when more greenhouse gases are introduced into them," he said.

"Changes in the circulation in the atmosphere might have had a much larger effect than previously thought, but these changes may also have been induced by greenhouse gases."


At the very least, the author realizes that greenhouse gases could have induced the energy transport from the equator to the arctic. And that this change isn't the only explanation for the temperature amplification in the arctic. If you're looking for someone in denial about AGW, this author is not the one for you.


RE: Wrong again Masher
By masher2 (blog) on 1/5/2008 1:58:11 PM , Rating: 2
I'm sorry, but you're grasping at straws here. Let's summarize what the author says here:

- the direct cause of the rapid melting is definitely not due to global warming alone.
- the indirect cause (the underlying change causing the energy flow) is unknown. It might be global warming, or something else entirely.

If this is your idea of a resounding endosement of AGW, then there's no arguing with you. The author doesn't even refer to anthropogenic GW at all.

Finally, the second NASA study referenced above identifies those changes as a natural cycle, not linked to GW.


RE: Wrong again Masher
By Rovemelt on 1/7/2008 12:03:33 AM , Rating: 1
What part of this sentence from Graversen don't you understand?

"Many models suggest an increase in energy transport when more greenhouse gases are introduced into them," he said.


RE: Wrong again Masher
By modelmania on 1/7/2008 11:25:09 AM , Rating: 2
quote:
by Rovemelt on January 7, 2008 at 12:03 AM

What part of this sentence from Graversen don't you understand?

"Many models suggest an increase in energy transport when more greenhouse gases are introduced into them," he said.


I think Masher understands it fine.

1. There is no mention of "anthropogenic" in that sentence, and the VAST majority of the greenhouse gases on earth do not come from man. So your assumption that the sentence is referring to man-made greenhouse gases, seems a bit far fetched.

2. Models are NEVER evidence of ANYTHING. A model is just a representation of a belief system. When a belief system becomes evidence of something, you have crossed out of science into something else.

3. The models referred to are known to be highly inaccurate.

4. How does a model "suggest"?? What about the other models (not included in the "many") that don't "suggest an increase in energy transport"?

AGW zealots continually fail to recognize that models and theories are NOT evidence. Einstein's General Theory of Relativity is not evidence. It is a theory. And, I might point out, a very good theory, because (a) nobody has ever found a counterexample and (b) it predicted several phenomena before they were seen that were subsequently measured and verified to extreme precision. These are the general scientific criteria for good theories.

The GCM models that AGW zealots revere as the gospel have NEVER accurately predicted anything and there are numerous examples where observations run counter to the models.


RE: Wrong again Masher
By Rovemelt on 1/7/2008 6:01:31 PM , Rating: 2
First paragraph of the paper Masher cites (after the abstract):

quote:
The recent warming of the Earth’s surface is most probably due to an increase of atmospheric greenhouse-gas concentrations. (8) Although most greenhouse gases are fairly uniformly distributed around the globe, the temperature response to greenhouse-gas forcing is thought to be larger in polar than equatorial regions.


Hey, look up reference 8 and what do we find? This:

http://www.aaas.org/news/press_room/climate_change...

Golly!!! He references the IPCC 2007 report. Not that Masher wants you to understand that THIS PUBLICATION IS BUILT ON THE CONSENSUS VIEW AMONG CLIMATE SCIENTISTS THAT HUMANS ARE ADDING CO2 TO THE ATMOSPHERE WHICH IS TRIGGERING AN INCREASE IN GLOBAL TEMPERATURES.

last paragraph from the Nature paper:

quote:
Our results do not imply that studies based on models forced by anticipated future CO2 levels are misleading when they point to the importance of the snow and ice feedbacks. It is likely that a further substantial reduction of the summer ice-cover would strengthen these feedbacks and they could become the dominant mechanism underlying a future Arctic temperature amplification. Much of the present warming, however, appears to be linked to other processes, such as atmospheric energy transports.


Ok, fine. They suggest that energy transport is responsible for the amplification of the arctic warming. AMPLIFICATION over existing forcing from rising CO2 levels as described in the 2007 IPCC report.

Follow closely now. This is from the interview with the lead author:

http://news.nationalgeographic.com/news/2008/01/08...

Nobody knows how much of this change is the result of human emissions of planet-warming gases such as carbon dioxide, but it's likely that they play a role. (the change they are referring to is change in energy transport)

" Many models suggest an increase in energy transport when more greenhouse gases are introduced into them, " he said.

" Changes in the circulation in the atmosphere might have had a much larger effect than previously thought, but these changes may also have been induced by greenhouse gases. "

Ok...not that the author actually ran that model and tested it (which he should have IMHO), but he acknowledges that greenhouse gases may have induced the energy transport change. That means it's actually not natural, as greenhouse gases are increasing due to human activity (note, this is where Masher's spin--the title of this blog post--comes in again). He even gives us an idea of the amplification on the warming of the arctic from this process:

" We are not saying this is the only explanation," says Graversen, "this could explain maybe 25% of the amplification of warming in the Arctic. "

The idea is that some of the rapid melt is from a change in heat transport, but the AGW forcings are still there and heating up the arctic. The author is not debating AGW at all. The whole point of the paper is to help explain why the melt is happening faster than the AGW models predict. It looks like a combination of AGW along with changes in heat transport (which also, according to the author, can happen when greenhouse gas concentrations increase.)

And finally, where is the CO2 increase coming from?

Human activity. Since the industrial revolution, the concentration globally has increased by over 30%. Volcanoes contribute far, far less compared to humans.

I fully understand what the goal of models are. Models are simply ways to quantify understanding of climate. They will never be perfect and they will never be able to forecast the future exactly. But the models we have right now are our best tools to explain what is happening and what will happen in the future. Global temperatures have followed CO2 levels closely for the last century and nobody challenges the fact that CO2 absorbs infrared radiation. The entirety of the climate models are far too complex to simply form a direct correlation between CO2 and temperature as there are other forcings. But the forcings (water vapor, methane, cloud cover, etc.) are acting together in a way to warm the planet further.

But it doesn't matter, I'm sure, to many of the readers here. Even if the author said AGW was real right to your face, it wouldn't matter. Even if Steven Hawking said this:

quote:
As scientists, we understand the dangers of nuclear weapons and their devastating effects, and we are learning how human activities and technologies are affecting climate systems in ways that may forever change life on Earth,” said BAS member Stephen Hawking, the renowned cosmologist and mathematician.

“As citizens of the world, we have a duty to alert the public to the unnecessary risks that we live with every day, and to the perils we foresee if governments and societies do not take action now to render nuclear weapons obsolete and to prevent further climate change.


(which he has http://www.msnbc.msn.com/id/16670686/), it doesn't matter to people in denial. That's the nature of denial. You ignore facts and just accept what Masher has to say without question.


RE: Wrong again Masher
By modelmania on 1/8/2008 12:00:01 AM , Rating: 2
quote:
But the models we have right now are our best tools to explain what is happening and what will happen in the future.


This is circular nonsense to put it kindly. How can models be our "best tools to explain what is happening and what will happen"???????????????

Especially, when we:

a. Know for sure (100% certainty) that the models are wrong.
b. Know that the models have never predicted anything accurately.
c. Know that the models do not even match the past accurately.

Models and theories are only useful for predicting the future when they are proven to be extremely accurate over large domains of testing (as for example the General Theory of Relativity has proven to be a good theory).

The models to which you refer have repeatedly been shown to fail in major ways.

Most recently, for example, Douglass, Christy, Pearson and Singer point out in their paper "A comparison of tropical temperature trends with model predictions" published in Oct 2007 International Journal of Climatology:

quote:
The last 25 years constitute a period of more complete and accurate observations and more realistic modeling efforts. Yet the models are seen to disagree with the observations. We suggest, therefore, that projections of future climate based on these models be viewed with much caution.


To read the whole paper and see the massive failure of the models (all of them): http://static.scribd.com/docs/1q509sc82p1lh.swf


RE: Wrong again Masher
By Rovemelt on 1/5/2008 12:30:13 PM , Rating: 2
Ice core records in the antarctic do suggest that the antarctic has been warming along with the rest of the planet and that it will continue to warm with AGW:

http://www.agu.org/journals/scripts/highlight.php?...

Sorry, it's not a free article.

Hotter air holds more moisture, which is expected to increase snowfall in some areas of the antarctic. It doesn't seem entirely clear, based on what I've read, what process is responsible for the increase in ice mass in the core of the antarctic. Or the loss in mass in other parts.


RE: Wrong again Masher
By masher2 (blog) on 1/5/2008 12:40:29 PM , Rating: 2
1/5 of a degree temperature rise over the last 2 centuries, yes. But again, you've missed the point here. Most of that temperature increase occurred during the very rapid global warming seen from 1900-1940, a period in which industrialization had not yet substantially altered CO2 levels.

Over a centuries long scale, the entire planet has warmed...we did, after all, just recently exit an ice age. But warming in the 19th century warming, coupled with cooling today, 200 years later, does not fit with human-induced global warming.


RE: Wrong again Masher
By Rovemelt on 1/5/2008 1:35:20 PM , Rating: 2
No, I haven't missed the point at all. YOU are clearly missing the point...the paper does not debunk at all the idea that humans are causing the planet to warm from increased CO2 emissions. The scientists who wrote that paper acknowledge that and implicitly support AGW through their research. You're just stubborn. The lead author clearly stated in an interview that the warming amplification in the arctic is from a combination of AGW and a change in energy transport which may also be caused by AGW. Nobody is arguing about where the increase in greenhouse gases are coming from, and the author clearly suggests that greenhouse gases are contributing to the warming there.


RE: Wrong again Masher
By grenableu on 1/5/2008 2:02:03 PM , Rating: 2
Please explain how the south pole warming in 1906 then cooling in 2006 proves humans are causing global warming.


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