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Cause of Global Warming 'Hiatus' Found Deep In the Atlantic
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.
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.
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!
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.
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.
"First they came for the slanderers and i said nothing."
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.
Pain is merely failure leaving the body
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.
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"?
Why would anyone engrave "Elbereth"?
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.
Science is all about firing a drunk pig out of a cannon just to see what happens.
Shrinking vertically is the real fear; the thermohaline circulation is highly sensitive to salinity (now, if only I knew what the word haline meant, and what happens when ice melts in seawater...), and the larger scale thermohaline circulation could very realistically shut down, or shrink to vertical levels making it near-useless for global heat distribution, if given proper breakdown of thermal gradients and salinity barriers; with it the most important currents (to a lot of places that are today habitable) would be fundamentally altered.
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.
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:
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.
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.