And there is more:Forecasts of climate change are about to go seriously out of kilter. One of the world's top climate modellers said Thursday we could be about to enter "one or even two decades during which temperatures cool.
"People will say this is global warming disappearing," he told more than 1500 of the world's top climate scientists gathering in Geneva at the UN's World Climate Conference.
"I am not one of the sceptics," insisted Mojib Latif of the Leibniz Institute of Marine Sciences at Kiel University, Germany. "However, we have to ask the nasty questions ourselves or other people will do it."
Few climate scientists go as far as Latif, an author for the Intergovernmental Panel on Climate Change. But more and more agree that the short-term prognosis for climate change is much less certain than once thought.
Latif predicted that in the next few years a natural cooling trend would dominate over warming caused by humans. The cooling would be down to cyclical changes to ocean currents and temperatures in the North Atlantic, a feature known as the North Atlantic Oscillation (NAO).
Breaking with climate-change orthodoxy, he said NAO cycles were probably responsible for some of the strong global warming seen in the past three decades. "But how much? The jury is still out," he told the conference. The NAO is now moving into a colder phase.
Latif said NAO cycles also explained the recent recovery of the Sahel region of Africa from the droughts of the 1970s and 1980s. James Murphy, head of climate prediction at the Met Office, agreed and linked the NAO to Indian monsoons, Atlantic hurricanes and sea ice in the Arctic. "The oceans are key to decadal natural variability," he said.
Another favourite climate nostrum was upturned when Pope warned that the dramatic Arctic ice loss in recent summers was partly a product of natural cycles rather than global warming. Preliminary reports suggest there has been much less melting this year than in 2007 or 2008.
In candid mood, climate scientists avoided blaming nature for their faltering predictions, however. "Model biases are also still a serious problem. We have a long way to go to get them right. They are hurting our forecasts," said Tim Stockdale of the European Centre for Medium-Range Weather Forecasts in Reading, UK.
The world may badly want reliable forecasts of future climate. But such predictions are proving as elusive as the perfect weather forecast.
7 comments:
Given it's name, I wonder how the NAO could affect global climate so much. The article on it on wikipedia says that the main affect is on Europe, with a weaker impact on eastern North America. It also says that it is mainly an atmospheric pehnomenon, not involving the ocean so much as El Nino/a.
Maybe wikipedia's explanation is not accurate or complete. And given the privincialism of some people, a cooling in eastern North America may as well be a global cooling. Nonetheless I wonder if Latif et al have suggested how such a regional phenomenon could overwhelm AGW for decades.
Roger
I have always believed the above was more or less certain to happen, sooner rather than later. The science is new, complex on an incredible scale and the models relatively crude.
The disturbing question is why so many scientists have felt the need to bow the knee to a political organisation like the IPCC and pronounce certainty when there was none. Perhaps Michael Tobis has the answer.
"In many ways we know more about what will happen in the 2050s than next year," said Vicky Pope from the UK Met Office.
There's a remarkable statement. Funny how the measured increases in global temps represented global warming due to GHGs, but a global downturn is just natural variation. I think Vicky needs a reminder from Peilke Sr. that there is no heat in the pipeline. If the greenhouse effect works as described, then its effect occurs every day. More CO2 in the atmosphere should mean greater planetary heat content. Either that additional heat is hiding somewhere, or the hypothesis has a hole in it. Is there a bigger question in climate science today? Where the heck is the heat? While measured temps may go up and down, total heat content should be going up every year. It seems to me that until you account for the missing heat energy, the entire greenhouse hypothesis has to be considered unsupported.
Regardless of how little we understand about the science, the important thing to remember is that we absolutely must use govt to drastically change every aspect of our lives -- and as soon as possible.
What Vicky Pope really means is that predictions about the 2050s are much safer since they can't be shown to be totally wrong for more than 40 years (by which time most of the current observers and predictors will probably be dead). By contrast, the UK Met Office's seasonal predictions for the last few years have been the laughing stock in England. Even more ridiculous, and more embarrassing is the NSIDC's Aug. 19, 2009 report of the predicted Arctic minimum ice extent made by 13 pan-arctic experts (based on end of July data). All 13 predictions are in the range 4,200,000 sq. km to 5,000,000 sq. km and less than three weeks later we are very near the minimum which appears almost certain to be well above 5,000,000 sq. km. These expert predictions are almost as misguided as Dr. Mark Serreze's June 2008 statement that there was more than a 50:50 chance that the Artic would be ice-free late in the summer of 2008. (He was only off by a mere 4,650,000 sq. km.) What Vicky Pope might have said that would have been more accurate is "What we know about the climate over the next year is almost minimal. Therefore, our knowledge of the climate in the 2050s can't be much less".
The more our hypothesis fails to predict the world, the more confident we are that our hypothesis is correct.
Cognitive dissonance in action.
"What Vicky Pope really means is that predictions about the 2050s are much safer since they can't be shown to be totally wrong for more than 40 years (by which time most of the current observers and predictors will probably be dead). By contrast, the UK Met Office's seasonal predictions for the last few years have been the laughing stock in England."
Indeed. Vicky Pope was quoted as saying, "In many ways we know more about what will happen in the 2050s than next year,"...
...but I can't imagine what science she would point to that would support that statement. I'd guess I'd could say with 90 percent certainty that the global average satellite (or surface) temperatures next year will be within +/- 0.4 degree Celsius from this year's temperature. I can't imagine anyone making a similar claim for the 2050s.
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