 from about 14,500 years ago--coming out of the last glacial maximum--to 10,000 years ago, as deduced from Greenland ice cores in unrelated research)
ANCIENT WARMING: The estimated temperature variation (from right to left) from about 14,500 years ago--coming out of the last glacial maximum--to 10,000 years ago, as deduced from Greenland ice cores in unrelated research
Image: WIKIMEDIA COMMONS/MERIKANTO
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The Best Science Writing Online 2012
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Climate models of the past, present and future seem to be in no short supply these days. But a new and dynamic picture of climate change appears in this week's Science, one that could affect the way future conditions are predicted.
Recent history has been kind to humans, providing a relatively stable climate for about the past 10,000 years. Many previous models have re-created short glimpses of this past.
But, says Axel Timmermann, a professor of oceanography at the University of Hawaii at Manoa, "None of these snapshots were able to capture abrupt climate change and transition," thereby making them less useful for predicting coming sudden shifts. Even if the near future doesn't unfold like the 2004 climate-gone-haywire film The Day After Tomorrow, scientists need to be able to produce accurate models of what abrupt change (more likely spanning hundreds or thousands or years, rather than days) would look like and why it might occur, explains Zhengyu Liu, lead author of the study and director of the University of Wisconsin–Madison's Center for Climate Research.
The new computer simulation takes a stab at doing just that. Based on the National Center for Atmospheric Research's Community Climate System Model, it gives scientists a novel—and, so far, reliable when checked against data from ice core samples—understanding of some causes and effects of rapid climate change.
Liu and his colleagues started their modeling at about 21,000 years ago—the zenith of the last ice age. But they've been especially interested in the most recent period of abrupt global warming, the Bølling-Allerød, which occurred about 14,500 years ago when average temperatures in Greenland rose about 15 degrees Celsius in about 3,000 years. The causes of the warming remain debated, but Liu and his team homed in on the melting glacial water that poured into oceans as the ice receded, paradoxically slowing the ocean current in the North Atlantic that keeps Europe from freezing over. Should ice in Arctic regions, such as Greenland, melt again, the globe may face a similar situation, sending Europe into a colder age despite warming taking place elsewhere.
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Add CommentIn the July issue of the International Journal of Global Warming, Bo Nordell and Bruno Gervet of the Department of Civil and Environmental Engineering at the Lulea University of Technology in Sweden have come up with a remarkable finding that completely changes the way we understand global warming. I can't overemphasis the importance of this message; it concerns peer reviewed science:
Reply | Report Abuse | Link to thisThe scientist's calculations show that three fourths of accumulated heat is from heat emissions. In other words, most of the global warming is from heat humans have generated, not from increased levels of greenhouse gas in the air.
http://www.sciencedaily.com/releases/2009/07/090713085248.htm
Trapping Carbon Dioxide Or Switching To Nuclear Power Not Enough To Solve Global Warming Problem, Experts Say
ScienceDaily (July 13, 2009) Attempting to tackle climate change by trapping carbon dioxide or switching to nuclear power will not solve the problem of global warming, according to energy calculations published in the July issue of the International Journal of Global Warming.
The reason I comment on it here is because I doubt that the climate models used (the Phoenix" and "Jaguar") took into consideration heat generated by geologic events or forest fires. Basically, all climate models will now need to be retooled to accommodate the above paradigm shift.
You're trying to make sense of a scientific study by interpreting a sensationalist article on a free web site about it, written in a way that makes it utterly impossible to comprehend what the original authors are trying to say.
Reply | Report Abuse | Link to thisGo get the original study, read and understand it, and come back with a report.
Whoever says that 75% of global warming comes from direct anthropogenic heat emissions is so many orders of magnitude off that it's hard to decide if one should laugh or cry. You only need high school physics to figure this out.
Ralf123: Instead of being difficult, perhaps you would be so kind as to constructively interpret the article yourself. Frankly, I've met a lot of people like you who are good at cutting others down, but aren't capable of furnishing their own interpretation. I stand by my original interpretation: 3/4ths of the accumulated heat (i.e. global warming) is from anthropic heat emissions, not anthropic greenhouse gas emissions.
Reply | Report Abuse | Link to thisBy the way, I would like to remind you that if it were so straight forward, then either the article wouldn't have been peer review, or anthropic heat emissions would be taken into account by current climate models already.
"a sensationalist article on a free web site"
Reply | Report Abuse | Link to thisUhm, scientificamerican.com is free too. At least this article. I looked at the other article. If you think that's sensationalist, I'd hate to expose you to anything truly enthusiastic - you might have a heart attack.
"Whoever says that 75% of global warming comes from direct anthropogenic heat emissions is so many orders of magnitude off that it's hard to decide if one should laugh or cry."
Let's try it this way.
7 billion people = 7 billion light bulbs
lets say 1 in 7 has an automobile. What is the efficiency of an internal combustion engine?
"Most steel engines have a thermodynamic limit of 37%. Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%"
From, you guessed it wikipedia.com (eek another free site)
If it isn't coming out as work - it's coming out as heat.
That's only autombiles. Now let's consider all the coal plants, light bulbs, industrial activity, ad nauseum.
I'm not saying the article is right - I am saying it's worth considering. I suppose I could also say I wouldn't put my face on an engine that had been running for any length of time.
The basic premise sounds intriguing, but if it's true, then it does two things:
Reply | Report Abuse | Link to this1. Falsifies the AGW premise, so it kills the issue of controlling CO2.
2. Begs the question as to what to do next. If the heat generated is shown to be radiating out into space as quickly or almost as quickly as it is building up (if it actually is building up; a point that I have yet to see clarity on given the recent controversy over the hair on the back of the neck raising coincidence that Hansen led GISS consistently produces higher anomalies than other researchers ), then should anything be done at all?
If any and all energy usage is to blame is it then realistic to condemn mankind back to the Stone Age? Or should we invoke the cautionary principle and say that an Ice Age is really mankind's biggest imminent threat, so burn, baby burn, to keep the Ice Age away?
I have heard that temperatures in the upper atmosphere are cooling...meaning that increased lower heat is not escaping...this would indicate the greenhouse effect. By the way, we would survive an Ice Age...it's the possibility of entering the methane age with 40+ degrees C of warming that is our biggest threat.
Reply | Report Abuse | Link to thisI still maintain that global warming requires the same actions as simple common sense on other grounds. The petroleum age is in its dying stages (according to USGS stats), and the world needs to get on with finding a new energy source for that reason. OPEC statements only suggest that demand will be met until 2030...and that's OPEC (I wonder what the truth is). Burning coal has been linked to health problems, so that isn't a very good energy source either. One would think that building wind turbines and solar panels would be a really good idea, but improving that technology would also be helpful...worth a few billion a year in research.
"Begs the question as to what to do next"
Reply | Report Abuse | Link to thisWe reduce our global population.
Personally I think this will be done for us but I'm a pessimist on that subject.
Ok, some basic math and physics:
Reply | Report Abuse | Link to thisEarth's diameter: 12,756 km
Solar constant (in space): 1,368 W/m^2.
Earth's surface incident to solar radiation: 1.3E14 m^2
Solar power incident on Earth: 1.75E17 W
Humanity's energy consumption is between 15 and 20 TW. Even allowing for horrible overall efficiency, you end up with about 4 orders of magnitude difference. A single hurricane churns about the same amount of power as all of humanity.
Oh and I did not say that all free sites are garbage. A site that finances itself though advertising however has an agenda, just like every other news outlet. Just like you can't rely on Wikipedia as absolute truth (though it can give you good initial information and pointers), you shouldn't rely on an outlet like SD for scientific facts. It is entertainment.
P.S. http://en.wikipedia.org/wiki/Earth%27s_energy_budget has a pretty good overview. It cites a forcing from anthropogenic greenhouse emissions of about 2.4 W/m^2. 20 TW divided by the Earth's surface is about 0.04 W/m^2. So the greenhouse effect is 50 times stronger than our energy use.
Reply | Report Abuse | Link to thisRalf123: Thank you for your constructive analysis. I (somewhat) regret my acidic response to your first comment, and I've taken the further step of downloading the paper ( http://inderscience.metapress.com/media/159rj6a7hp7xupae0mwk/contributions/n/5/4/7/n547110644753t52.pdf ) to further scrutinize. By the way, on the fly I would suggest if a system is in balance could indeed be burdened by addition heat emissions. Upon reflection, the reason for my visceral reaction to your first critical posting was because I have ran into all too many people who knee jerk reject new ideas due to ossified preconceptions. Quote by Albert Einstein: "We can't solve problems by using the same kind of thinking we used when we created them."
Reply | Report Abuse | Link to thisBy the way: "Few people are capable of expressing with equanimity opinions which differ from the prejudices of their social environment. Most people are even incapable of forming such opinions." --Albert Einstein
Well, if I wanted to know if there is a heat build up or not, I guess I would look in the world's oceans. We know how to calculate the heat content of oceans but it is a rather laborious process to keep data current. For instance, El Nino is back so the water off Baja is getting hotter and other places are getting cooler.
Reply | Report Abuse | Link to thisLooking at oceans also gives us an idea of whether ice bergs are having an impact as they would if a lot more ice were melting. My impression is that the people crowing the loudest about ocean heat lately are the AGW doubters. Silence in some quarters speaks for itself.
Hmm, ten people this last week perished from hypothermia while climbing mountains in Japan. Could be something to the idea that the upper atmosphere is getting colder.
Reply | Report Abuse | Link to thisClimate simulation models are about the worst investment of taxpayers money I can think of. Uncle Sam spends more than a billion dollars on climate research each year and all we get for it are worthless and dishonest model predictions. It is not just carbon dioxide but a host of other parameters in there that can be adjusted to get any desired output. The so-called "global temperature" curves that are input into models are themselves cooked so the models begin with fictional temperatures to start with. Let me take NOAA's chart for the eighties and nineties as an example. It has a rising red triangle on the right hand side - the late twentieth century warming - that starts about 1977. Prior to that there was no warming whatsoever. Fortunately this period overlaps with accurate satellite measurements that started in 1978. And satellites cannot find that warming. What they do find is a multi-year temperature oscillation where warm El Nino periods alternate with cool La Nina periods. There were five such cycles in a twenty year period. When both curves are plotted on the same graph the NOAA chart shows not the slightest resemblance to reality. Close observation reveals that they did get the first four El Nino peaks about right. The fifth one was out of line so the simply raised it up, and then for good measure they raised the rest of the curve too. But what did they do with the cool La Nina periods that exist between the El Nino peaks? Its simple: they all got erased. Which makes that graph and other similar ones a scientific fraud. This is not a minor matter because the imaginary warming they created this way is the same warming that Hansen in 1988 said was caused by the greenhouse effect of carbon dioxide. And that argument was the foundational argument for establishing the IPCC in 1988. I will let you figure out the rest for yourself. And as a taxpayer I resent having billions spent to fight an imaginary warming.
Reply | Report Abuse | Link to thisClimate simulation models are about the worst investment of taxpayers’ money I can think of. Uncle Sam spends more than a billion dollars on climate research each year and all we get for it are worthless and dishonest model predictions. It is not just carbon dioxide but a host of other parameters in there that can be adjusted to get any desired output. The so-called "global temperature" curves that are input into models are themselves cooked so the models begin with fictional temperatures to start with. Let me take NOAA's chart for the eighties and nineties as an example. It has a rising red triangle on the right hand side - the late twentieth century warming - that starts about 1977. Prior to that there was no warming whatsoever. Fortunately this period overlaps with accurate satellite measurements that started in 1978. And satellites cannot find that warming. What they do find is a multi-year temperature oscillation where warm El Nino periods alternate with cool La Nina periods. There were five such cycles in a twenty year period. When both curves are plotted on the same graph the NOAA chart shows not the slightest resemblance to reality. Close observation reveals that they did get the first four El Nino peaks about right. The fifth one was out of line so the simply raised it up, and then for good measure they raised the rest of the curve too. But what did they do with the cool La Nina periods that exist between the El Nino peaks? It’s simple: they all got erased. Which makes that graph and other similar ones a scientific fraud. This is not a minor matter because the imaginary warming they created this way is the same warming that Hansen in 1988 said was caused by the greenhouse effect of carbon dioxide. And that argument was the foundational argument for establishing the IPCC in 1988. I will let you figure out the rest for yourself. And as a taxpayer I resent having billions spent to fight an imaginary warming.
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