Study links swings in North Atlantic oscillation variability to climate warming
January 13, 2009Using a 218-year-long temperature record from a Bermuda brain coral, researchers at the Woods Hole Oceanographic Institution (WHOI) have created the first marine-based reconstruction showing the long-term behavior of one of the most important drivers of climate fluctuations in the North Atlantic.
The North Atlantic Oscillation (NAO) is a wide-ranging pressure seesaw that drives winter climate over much of North America, Europe and North Africa. Past reconstructions of the NAO have relied mainly on terrestrial, or land-based records, such as tree ring chronologies combined with ice cores and historical climate data. Those records do not fully capture oceanic processes linked to NAO variability, and short instrumental records from relatively few locations limit the understanding of ocean-atmosphere dynamics with regard to NAO behavior.
"By analyzing the coral, we were able to look at changes in the ocean relative to changes on land," said Nathalie Goodkin, lead author of the study published in the December issue of the journal Nature Geoscience. "Because they are slow growing and have long life-spans, corals can provide high resolution records that are well dated and centuries long."
As they grow, corals accrete seasonal and annual growth layers, similar to tree rings. The proportions of trace elements versus the major element (calcium) found in the layers of the skeleton largely depend on the temperature of the seawater in which it was formed. By analyzing the strontium to calcium ratio in the Bermuda brain coral, Goodkin and colleagues — WHOI scientists Konrad Hughen, Scott Doney and William Curry — were able to reconstruct monthly changes in ocean temperatures and evaluate variability of the NAO during both cold and warm periods from the Little Ice Age (1800�) to modern day.
The research team found the variability of the NAO decade-to-decade (multi-decadal scale) has been larger, swinging more wildly, during the late twentieth century than in the early 1800s, suggesting that variability is linked to the mean temperature of the Northern Hemisphere. This confirms variability previously reported in past terrestrial reconstructions.
"When the Industrial Revolution begins and atmospheric temperature becomes warmer, the NAO takes on a much stronger pattern in longer-term behavior," said Goodkin. "That was suspected before in the instrumental records, but this is the first time it has been documented in records from both the ocean and the atmosphere."
The North Atlantic Oscillation is described by the NAO index, calculated as a weighted difference between the polar low and the subtropical high during the winter season. In a positive phase, both the low-pressure zone over Iceland and high pressure over the Azores are intensified, resulting in changes in the strength, incidence, and pathway of winter storms crossing the Atlantic. In a negative phase, a weak subtropical high and a weak Icelandic low results in fewer and weaker winter storms crossing on a more west-east pathway.
The NAO index varies from year to year, but also exhibits a tendency to remain in one phase for intervals lasting more than a decade. An unusually long period of positive phase between 1970-2000 led to the suggestion that global warming was affecting the behavior of the NAO.
"Anthropogenic (human-related) warming does not appear to be altering whether the NAO is in a positive or negative phase at multi-decadal time scales," said WHOI paleoclimatologist Konrad Hughen. "It does seem to be increasing variability. Clearly, this has implications for the future."
"As temperatures get warmer, there's potential for more violent swings of the NAO — the phases becoming even more positive and even more negative," Hughen added. "If the NAO locks more into these patterns, intense storms will become more intense and droughts will become more severe."
The climatic influence of the NAO extends from the eastern United States to Western Europe, impacting human activities such as shipping, oil drilling, fisheries, hydroelectric power generation and coastal management. Improving the ability to predict shifts in the phase and intensity of the NAO is a prerequisite to mitigating the economic impacts of future climate change.
While additional modeling and palaeoclimatic studies are needed, a broad distribution of marine records could advance our knowledge of NAO variability and serve to improve future projections, said Goodkin, now an assistant professor in the Department of Earth Sciences at the University of Hong Kong.
Nature GeoScience paper: Increased multidecadal variability of the North Atlantic Oscillation since 1781 http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo352.html
Source: Woods Hole Oceanographic Institution
Jul 09, 2009 |
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Good science, bad conclusions.
The only thing this study says is that the variability of the NAO is greater with greater global temperatures.
There is nothing here to indicate whether the warming is anthropogenic or not.
It could just as easily be related to changes in output from the sun.
They said that the warming began in the industrial era. that correlates to exactly when we started pumping greenhouse gasses into the atmosphere. While it doesn't outright say the effects are anthropogenic, the data does suggest that human activity has contrtributed in some way.
I would have to agree,but good luck finding a brain coral a couple thousand years old.
This is a chicken-and-egg problem. Just because the variation starts around around the same time it does say which is the leader or even if there is a connection.
A simple test would be the amount of greenhouse gases (natural and man-made) present 218 years ago and how much it would take to make a measurable difference. Or is that too much of a jump for the religious faction?
Global temperatures have been steadily rising. There was a little cooling this last year due to dramaticaly decreased solar flare activity, but before that the sun wasn't firing off any unusual amount of energy. While solar activity may have given a small boost to the warming, the main cause is here on Earth and still in play.
Don't make a scientific argument into a conspiracy theory.
And 9/10ths of the law is inefficient
http://www.noaane...ats.html
The long term mean of US temperatures is shown here.
http://www.noaane...temp.png
Meanwhile CO2 is doing this.
http://www.esrl.n.../trends/
Happer, the Cyrus Fogg Brackett Professor of Physics, said in an interview. %u201CCarbon dioxide is not a pollutant. Every time you exhale, you exhale air that has 4 percent carbon dioxide. To say that that%u2019s a pollutant just boggles my mind. What used to be science has turned into a cult.%u201D Happer served as director of the Office of Energy Research in the U.S. Department of Energy under President George H.W. Bush and was subsequently fired by Vice President Al Gore, reportedly for his refusal to support Gore%u2019s views on climate change.
Al Gore should not have fired someone for their beliefs.
Physics professor William Happer GS %u201864 has some tough words for scientists who believe that carbon dioxide is causing global warming. %u201CThis is George Orwell. This is the %u2018Germans are the master race. The Jews are the scum of the earth.%u2019 It%u2019s that kind of propaganda,%u201D
Actually, CO2 is a known pollutant. It is known to contribute to the greenhouse effect and it is known that it's potentialy deadly to humans in large amounts. There's no scientific support behind this man's statement.
Yes, compare us to Nazis. Compare us to the guys who enslaved, tortured, and killed millions based on heritage. Compare us to the guys who called theoretical physics "Jew science." Hey, while your at it, mot of us are liberal so you might as well start calling us commies. Oh, and pagans liked trees too, so I guess we're pagans too. And we talk about a planet, aliens come from planets, we're aliens too!
Resorting to the old Nazi-mudsling is a desperate move. If your going to argue against scietific consensus, argue with science.
William Happer, Chairman of the Board of Directors, also Eugene Higgens Professor of Physics, Princeton University
Funding
$50,000 from ExxonMobil Foundation in 1999 for support for science and public policy education programs
$50,000 from ExxonMobil Foundation in 2000 for general support
$60,000 from ExxonMobil Foundation in 2001 for climate change work
$80,000 from ExxonMobil Foundation in 2001 for global climate change program in 2002, plus a further $10,000 for the Awards Dinner
$95,000 from ExxonMobil Foundation in 2003 for Global Climate Change Program
$145,000 ExxonMobil Foundation in 2004 for climate change work and a further $25,000 from Exxon Corporation for "Awards Dinner -- Climate Change Activities
$90,000 from ExxonMobil Foundation for, according to the Institute's IRS return, climate change and a further $25,000 from ExxonMobil Corporate Giving for Awards Dinner and General Operating Support
$85,000 from ExxonMobil Corporate Giving for General support and annual dinner in 2006.
Might as well trust a Greenpeace funded Scientist
Why? Their agenda is, if anything, more extreme that the oil companies.
Your ranking of 1 for a self-evident fact is a bit harsh. May I ask your reasons?
Science is about seeking verifiable truth(s) through the use of logic and evidence. You, my friend, do neither.
Simply claiming over and over again that the recent warming occurs over a time scale that coincides with increase in CO2 does not prove that human are responsible for the warming. My year 8 science students can see through this logic with no trouble at all because they know it violates the basic tenets of the scientific principle.
All it takes is a rudimentary knowledge of science to realize that CO2 levels did not start to significantly increase until the 1940's. This is long
after the increase the oscillations of the NAO index which started to occur in the 1860's.
All it takes is common sense to know that when we first started burning coal for fuel on a large scale, i.e. the industrial revolution, we started pumping out large amounts of greenhouse gasses. It's true that there was more being pumped out in the twentieth century, but that's because we had more industrial developement, automobiles had become more common, and we discovered methods of refining oil. It all started back in the industrial revolution.
Do I really need to tell you how the greenhouse effect works? Seriously? Ok, let's do this.
The sun, as you well know, gives off a crap load of light. This light is found in almost all of the spectrums of light (radio, microwave, infrared, visible, ultraviolet, x-ray, gamma ray) with less gamma than anything else(lucky for us). Now, of that emmitted light, most of the x-rays are kept from the surface of Earth by our ionosphere and most of the radiowaves are blocked out by the various gasses in our troposhpere like CO2 and water vapor. The Earth absorbs just about all of the light that makes it to the surface and thu warms up enough for life to exist. Now the Earth also emits light, mostly at radio wave frequency. Do you remember those lovely gasses that reflected some (but not all)of the sun's radio waves? Well, it works both ways. The gasses in the air reflect a portion of the energy carried by the radio waves back toward Earth's surface. This in turn heats the Earth a little more, then more energy is given off as light which is then partialy reflected again. Left unchecked, this proccess grows exponentialy and eventualy can turn a planet into a bright, hot hellscape. This proccess has been left unchecked, so you can see the end result at the NASA web page. Earth is special, however. We have large bodies of liquid water, which can trap both heat and the green house gasses that would otherwise spell doom for life on Earth. Ice has also trapped some green house gasses like CO2, Methane, and the obvious H2O. The oceans, however, can only absorb heat and gasses at a finite rate that will decrease if the oceans are too warm. When we put green house gasses into the air, we increase the amount of energy reflected and speed up the process. The extra energy is, of course, absorbed by the oceans, thus warming the oceans. This warming helps to speed the melting of sea ice. Since the ice was trapping some amount of gasses, more greenhouse gasses are released upon the melting. If left unchecked, eventualy the ocean will not be able to absord heat quickly enough to sustain desirable climate. Since i know you'll probably ask, the decreasing ability of the oceans to absorb heat is due to simple thermodynamics. The smaller the difference in heat, the slower the transfer of energy is. The reason why we believe that humans are largely responsible for the recent warming trend is because we have been pumping out large amounts of CO2 and H2O whenever we burn things(coal, oil, natural gasses) for energy and fuel. We've also been letting off other greenhouse gasses like Methane with our increased cattle heards. We have further screwed things up by deforrestization, trees being one of natures great ways of reducing CO2 and replenishing oxegen for the ozone layer. Oh, I forgot, the ozone layer is important because it is very good at blocking out UV rays. With its depletion, more UV rays (a high frequency and high energy form of light) are able to heat the surface of the Earth.
There's your brief sum up of the greenhouse effect and why we believe humans are major contributers. It's neither perfect nor complete, but that's what I'm giving you. Are humans 100% responsible? Of course not, that's just silly. But we are acting as catalysts to speed the proccess on its way.
Now that I have your attention - maybe I can temper your religious zeal.
I have a Doctorate in Astronomy so I beleive that I have a very good understanding of how the Green-house effect works. That understanding leads me and many other reputable scientists to conclude that, at worst, we could see a 0.6 to 1.0 C increase in temperature by 2100 AD.
While this is a serious concern in the long-term, it is not sufficient for us to commit economic suicide. Yes, we should reduce our reliance on non-sustainable sources of energy, such as fossil fuels. However, we should do so gradually over 60 to 100 years. It is madness to try and elimainate CO2 emisions by 2050 - particularly when the science tells us that we do not have to do this.
What we have here is a horribly wrong assumption. I have no religious zeal. religious zeal would suggest that I beleive in a supernatural power or powers no matter what evidence was thrown against me. My interpretation of commonly known science could not be considered religious zeal because of the lack of supernatural involvement. Also, I would like to point out that I have presented the reasonable arguments of my position with only the occasional outburst nonsensical gibberish. Please do not place my scientific oppinion among the fundementalist zealots that have caused so much trouble in the world.
Hey, good job. I was planning on getting my master's in astronomy.
Why is it maddness? Why is it economic suicide? Forgive me, but I just don't understand that reasoning. I believe it was Denmark ( or some other small, northern European country) that eliminated their own CO2 emmissions and are now selling off all their dirty energy sources to other countries. It took them a decade or two (I honestly can't remember exactly how long). They're a lot smaller than us, but what's to say we can't do the same thing in a slightly longer period? The building of the clean energy plants will create much needed jobs. The increase in fuel efficiency will allow American car companies to compete with foreign companies and thus will save thousands of jobs. Finding ways of reducing emmissions in industry will require more scientists and engineers, again, providing more jobs. As you yourself say, we need to get off our dependency on foreign oil. Why not make that all oil? The less we rely on other nations for our energy, the better off we'll be economicaly. Take global warming out of the picture for just a second, because I know people get worked up about it. What part of going green, specificaly, is harmful to us. Where is the bear trap that you seem to see but I cannot? Let's resolve this before further argument over the science of global warming, because congress isn't going to wait for the debate to end before they act. If there's anything that should be stopped, we should probably act immediatly. So educate me.
I guess we've been over this so many times that Ninderthana doesn't think it's worth the effort...
The country you were referring to is Sweden. Sweden reduced their hydrocarbon energy production to near zero net CO2 output.
Let's get back to that in a minute.
So is H2O. H2O is not classified as a pollutant although it is responsible for far more climate change than CO2 ever could be in addition to being quite deadly in large amounts. Just had to get that one out of the way.
Ok back to Sweden. Sweden is one of the largest countries in the EU. Problem is, it's one of the smallest by population (9 mil). Effectively something that will work for them might not work for anyone else.
Think of a sewer system for Fargo, North Dakota, then try to implement the same system in New York City, New York. It wouldn't work for obvious reasons.
You are absolutely correct. That's one of the reasons I think it wise to reduce all greenhouse gas emmissions rather than going on a CO2 witch hunt and completely forget about the others.
But why can't we adapt the system for a larger scale? I don't think we have a single state that isn't capable of providing enough renewable energy for their own citizens. Many of them can provide enoiugh for themselves and neighboring states. Think of Montana. They have a large, mountanous area that could be home to many a wind farm and only three people and a german shepard to take care of. (exageration, ha ha) I think the only problem you might run into would be New York City, but I think that a few windmills and solar panels on the roof would beable to provide power for each seperate building, thus providing a basic energy system upon which to build. I don't think the power companies can complain, because they would be the people installing and maintaining all the energy sources, so their profits probably wouldn't take a dive.
Think of Sweden as a small scale test that acts as proof of concept. Scale the whole thing up and adapt it to available resources and there really shouldn't be a problem.
The big problem with the renewable sources is the same problem they had long ago. During peak consumption they fail to reach peak generation. This can be completely circumvented if the focus was on transmission technology as opposed to generation technology.
Think on it this way, you could have thousands of solar generation stations around the world. If they can generate a petawatt each but can only transmit that energy a few hundred miles then the station is all but useless. What if they could transmit that energy anywhere in the world? Well the sun is always shining on the planet somewhere, over some sort of desert or plains area that can be used for this purpose. The research is focused in the wrong area. If you solve the transmission issue you solve a lot of other problems and also lower consumption of the current fossil fired plants by always using what you generate, rather than running at reduced capacity and wasting excess energy just to keep the turbine spinning regardless of the load.
As far as geothermal, I wouldn't recomend it on today's tech. We have a few geothermal buildings here, but they can barely support themselves.
As for nuclear, I'm against it for two reasons. First, it generates a lot of steam which, as you have repeatedly pointed out, is a worsew greenhouse gas than CO2. Second, if the states don't want to deal with their own stupid nuclear waste, they obviously aren't responsible enough to use nuclear power. Seriously, we don't want your crap, no matter how safe you all claim it is.
I think a relevant technology would be the metamaterial used for the cloaking devices. Efficient transmission of light. As light has momentum but no mass, it is effectively the efficient transportation of energy. Convert generated energy into a form easily transmitted through the material and badaboom, Nevada alone can provide power for the entire west coast.
As for nuclear, I'm against it for two reasons. First, it generates a lot of steam which, as you have repeatedly pointed out, is a worsew greenhouse gas than CO2. Second, if the states don't want to deal with their own stupid nuclear waste, they obviously aren't responsible enough to use nuclear power. Seriously, we don't want your crap, no matter how safe you all claim it is.
And this is exactly why Sweden's methodology won't work in the US. It's a mix of available infrastructure and current attitudes towards nuclear power.
Well the question is, how well do these materials work under water, underground, over extremely long distances, etc.
See this is another sticking point of the CO2 as a primary driver of AGCC. The industrial revolution started in the UK in the late 1700's. Steam engines were incredibly commonplace in the 1850's. There are no ties made to the CO2 of that era whatsoever, and realistically if CO2 was a main driver of climate, you would see an effect starting probably in the 1800's, not the mid-1900's as the theory focuses on now. Railways and steam ships were belching out massive amounts of CO2 yet that isn't brought into consideration because there was a strong cooling trend at that time.
So at what volume does CO2 begin to be a problem? Is there some sort of a critical CO2 production limit that changes it's effects in the atmosphere? This is another hole in the thought processes currently employed by the most fanatical of AGCC supporters in regards to CO2.
One could argue that the reason why these times are not included is because there was a strong cooling trend in the late 1800's and early 1900's, leaving us with a warming trend starting in the 40's and 50's allowing a neat coincidental package to build the theory around.
Theo, all "traditional" powerplants generate enormous amounts of steam. The steam is what actually turns the turbine generating the electricity, the coal, oil, nuclear material, biofuel, or geothermal energy is used to heat the water to the point of steam for this aim. People equate the exhaust they see from powerplants as being smoke, when in reality, the vast majority is steam and other constituents are typically colorless, like CO2, CO, and O2.
That's not the point I try to get after with that example. It's not about the specific resources that Sweden uses, it's the way they identified their available resources and capitalized on them for energy independence and very low emmissions. the U.s. i much bigger with much more restrictions, but we alo have way more resources, both natural and acedemic. We have the ability, we just need the initiative.
Yep, that's why my favorites are solar and wind. Zero emmissions. The only problem with wind turbines is that they can potentialy screw with locl avion populations. In my dream world, we cover the warm half of Mercury with solar panels and magicaly transfer all the energy back to Earth with near perfect efficiency.
There are three reasons why the effects of the greenhouse gasses took a little while to get things rolling. First, you're dead on with the critical emmission limit. There is a point where emmission go from harmless(nomadic tribes making fires to cook with) to dangerous(New Jersey starts needing outdoor air fresheners). Second, it takes time for things to get started. This article shows that things were starting to get a little messed up at the start, but it would have taken time for the enrgy to build up enough for us to actualy notice the effects of the poitive feedback. And third, the spread of industrialization slowley accelerated the proccess. When the UK and US were first industrializing, most of the world was still pretty backward. It wasn't until later until we started seeing major emmissions world wide. It kind of ties in with the noted lack of warming in the antartic. I think that it's slower down there because all the emmissions were in the northern hemisphere. You could also reason that since the energy would have been building up in the northern hemisphere more than in the southern, the energy could have just flowed over to the Aussies and escaped the sytem there.
Should I try shouting to the east really really loudly?
PMs.