Cause of Global Warming 'Hiatus' Found Deep In the Atlantic 465
vinces99 writes with news about a study that may account for a slowdown in air temperature rises. Following rapid warming in the late 20th century, this century has so far seen surprisingly little increase in the average temperature at the Earth's surface. More than a dozen theories have now been proposed for the so-called global warming hiatus, ranging from air pollution to volcanoes to sunspots. New research from the University of Washington shows the heat absent from the surface is plunging deep in the north and south Atlantic Ocean, and is part of a naturally occurring cycle. The study is published in Science. Subsurface ocean warming explains why global average air temperatures have flatlined since 1999, despite greenhouse gases trapping more solar heat at the Earth's surface. "Every week there's a new explanation of the hiatus," said corresponding author Ka-Kit Tung, a UW professor of applied mathematics and adjunct faculty member in atmospheric sciences. "Many of the earlier papers had necessarily focused on symptoms at the surface of the Earth, where we see many different and related phenomena. We looked at observations in the ocean to try to find the underlying cause." What they found is that a slow-moving current in the Atlantic, which carries heat between the two poles, sped up earlier this century to draw heat down almost a mile (1,500 meters). Most previous studies focused on shorter-term variability or particles that could block incoming sunlight, but they could not explain the massive amount of heat missing for more than a decade.
Every week there's a new explanation of the hiatus (Score:4, Interesting)
Sweet, I can't wait for next week's alternate explanation!
Go ahead "consensus" troll mods - do your worst to bury every skeptic questioning sketchy science on this story. Then go look in the mirror and call yourself a rational scientist.
Well, at last (Score:4, Interesting)
Not only does this explain a lot of the recent data, but it also directs attention to an ignored part of climatology: the vulcanism under the oceans and the warm currents they cause at very deep levels.
Good going, guys and guyettes!
Re:Every week there's a new explanation of the hia (Score:5, Interesting)
please link to an example of "sketchy science" that has been proved wrong by more solid, peer-reviewed science.
I know you're just smacking down a troll, but climate models have been over-estimating warming for years, as demonstrated by this science [ed.ac.uk].
That's not to say that climate models are bad science, they are good science investigating the nature of the earth; but people who put too much faith in them without evidence were performing bad science.
Re:Washington DC think tanks (Score:1, Interesting)
LOL realclimate.org (Score:0, Interesting)
Asking them for an unbiased scientific opinion is about as credible as asking foxes for an unbiased opinion on whether chickens are tasty.
The site gives proper scientists a bad name. Their only concern is looking after Hansen's reputation, and they gang up and abuse anyone who dares raise proper scientific questions, or who opens discussion about counter-evidence, or suggests that there is something we do not know about the subject. They think the planet works as trivially as a test tube.
And then they affirm their lack of scientific integrity with a site ban. Really, the site is best classified as comedy. They don't understand the basis of scientific inquiry nor the scientific method, and think that science is decided by unshakeable opinion and shouting people down.
Re:Every week there's a new explanation of the hia (Score:3, Interesting)
But it would contradict some of the fundamental assumptions of most of those models.
Which assumptions?
All climate models assume a lag between a cause and the observed results.
This just means the lag might be 30+ years.
Re:Every week there's a new explanation of the hia (Score:5, Interesting)
The "hiatus" isn't what people think - " this century has so far seen surprisingly little increase in the average temperature at the Earth's surface"
Note that the average temp is still rising even if more slowly than expected. But the entire planet doesn't warm or cool all at once.
During that "hiatus" the loss of ice cover, especially in the Arctic has been tremendous and that's noteworthy for 2 reasons.
The first is that the number of temperature monitoring stations in the Arctic is very poor. The other is that it takes a LOT of heat to melt ice - turning it to water at zero deg requires as much as raising room temp water to the boiling point.
Re:Every week there's a new explanation of the hia (Score:2, Interesting)
No, they want the science to be settled more-thoroughly before we re-model our entire society in response to it. Do you have any idea how many trillions we've wasted economically on the global warming thing? If they couldn't predict and can't explain the hiatus, that's just another sign that science and policymakers are being way too confident about the scientific underpinning for wasting trillions.
The real real truth goes something like this:
1) Scientists discover a possible global warming problem, but data isn't perfectly clear. However, there's a 5% chance it could fuck up all of human society in a few hundred years.
2) Scientists decide that nobody will take it seriously enough to take action, and decide that action is necessary, so they begin collectively fibbing about how solid the evidence is and how near and dramatic the impact is. They need to convince the sheeples to convince the government to do "the right thing". If there's any internal debate in the science community, it's squashed in the name of "don't let the sheeple see us disagreeing about the details! then they won't fix it!".
But the bottom line is: people aren't as stupid as you'd like to think they are, and they don't need the science community usurping the decision-making power by internalizing the debate and lying to everyone.
Re:Every week there's a new explanation of the hia (Score:5, Interesting)
If this paper were to turn out to be correct, current climate models are useless and will need to be completely reworked.
No model, in any branch of science or engineering, is complete and perfect; that doesn't mean they're useless [arstechnica.com].
I'm curious to see which fundamental assumptions made by current models you believe to be contradicted by this paper. To me it looks like they're simply pointing out a deep-ocean cycle that could soak up heat from the surface - not unlike the well-known ENSO, PDO and AMO cycles, which most models don't attempt to predict. Unless you think that "incomplete" means "fundamentally assumes that no other factors can exist"?
Re:This will be a thoughtful, productive discussio (Score:2, Interesting)
While there are indeed "five" known major mass extinctions, those aren't the only ones. There would be at least a dozen others.
And there are several of them(including some of the Big Five) where global warming is a possible explanation.. Paleocene-Eocene, Triassic-Jurassic and possibly Permian–Triassic .
The Clathrate gun hypothesis, is one explanation for them, flood basalts are another. But if you can offer your own thoughts, go ahead.
I doubt the models are expressly identical though, since modern ones have to account for human behavior, and while the Silurians are fun to watch on the Beeb, they aren't likely to be real.
Nor are Time Lords.
Re:Wait (Score:4, Interesting)
Deep ocean water is cold.
Because the Pacific ocean is thousands of kilometres wide, but only a couple of kilometres deep, changes in wind patterns can cover or uncover different layers of ocean waters.
If the pattern uncovers a deep layer (as happens during La Nina), then the atmosphere cools.
If the pattern covers the deep layers (as happens during El Nino), then the atmosphere warms.
This is above and in addition to any underlying warming from rising CO2 levels.
Since 2000 there's been an unusual number of La Nina years. Under normal circumstances, this should have produced a noticeably cool period, similar to the 1940s and 1890s. Instead the decade was still the warmest on record. Weird huh.
Re:Every week there's a new explanation of the hia (Score:4, Interesting)
It's generally thought that if the cycle does slow down enough, or shut down completely, the Ocean will lose its ability to sequester any more heat, and the result will be quite catastrophic to the current climate (in that places that were previously arable, will not be), and there's plenty of evidence that this has not only happened before, but triggered extinction events.
Currents in general are quite safe, and nobody's really worried about the ocean suddenly becoming stagnant.
Re:Every week there's a new explanation of the hia (Score:5, Interesting)
If this study is right then there will come a point when climate models are underestimating the warming again. The mechanism of this heat absorption is cyclical and eventually it will reverse leaving more heat in the atmosphere leading to rapid warming again. It's difficult if not impossible to put that into climate models partially because it's impossible (with our current knowledge) to know the timing of the switches in the cycle so models tend to just use the average which means sometimes their above the average and sometimes they're below.
The abstract: [sciencemag.org]
A vacillating global heat sink at intermediate ocean depths is associated with different climate regimes of surface warming under anthropogenic forcing: The latter part of the 20th century saw rapid global warming as more heat stayed near the surface. In the 21st century, surface warming slowed as more heat moved into deeper oceans. In situ and reanalyzed data are used to trace the pathways of ocean heat uptake. In addition to the shallow La Niña–like patterns in the Pacific that were the previous focus, we found that the slowdown is mainly caused by heat transported to deeper layers in the Atlantic and the Southern oceans, initiated by a recurrent salinity anomaly in the subpolar North Atlantic. Cooling periods associated with the latter deeper heat-sequestration mechanism historically lasted 20 to 35 years.
The question climate science deniers need to ask themselves is "If all of this heat is going into the ocean why hasn't it actually cooled rather than temperatures just sort of plateauing?" If all that heat is disappearing into the ocean and we're not actually cooling that means heat is still building up.
Re:Every week there's a new explanation of the hia (Score:3, Interesting)
Strange how, just a knee-jerk you'll find some people defending the science, there are those that have the same knee-jerk reaction against any findings in this area. With all that uncontrollable knee-jerking on both sides - it seems that we have another great argument for universal health care, to get people's knees fixed again... But I digress...
Whether climate change is man-made or not - I don't think there is too much debate left on the matter. But, I'm no climate scientist, so for me personally it's a matter of "belief" that mankind is behind this. We may get some theories and models wrong on how fast global warming works - or why there may be a hiatus in it.
The question of whether we're behind this - take two past events and see how much influence we might have:
Remember the Icelandic volcano a few years back - in response to the volcanic ash, we grounded a lot of flights for a few days - and even in that time, we could measure how much the air changed - just by taking planes out of the picture for a few days.
Secondly, if you think mankind's influence isn't large enough given the size of the planet - look back at climate records around the time Krakatoa blew up - that one mountain exploding had a measurable impact on temperature and weather for 5 years; so, if a _single_ mountain on one day can create that kind of change -- are you sure, all of our industries around the world together over the course of years CAN'T?
What the planet is "too large for", is for us to do some quick and easy experiments to actually test our hypotheses quickly - so climate science does what it can mostly from observation and trying to identify as many factors as possible that DO have a measurable impact in order to MODEL what's going to happen and then wait and see how close these models correlate with what's happening.
Re:Every week there's a new explanation of the hia (Score:5, Interesting)
Still useful... for what? that's the question.
If we're going to move to alternative energy, population control, costing in environmental damage as part of the economy, global justice, etc., climate models don't seem useful for that anymore. They are useful, but not useful enough for that application, still too wide an area of uncertainty. Nobody said the models had to be perfect, just fit for purpose.