Thursday, January 7, 2010
The following sample of stories from the past year show that much of the world has been experiencing a cold spell:
- Heaviest snowfall in Northern China in six decades (and 2008 was called "the coldest winter in 100 years")
- Across the South, Midwest, and Eastern seaboard [of the United States], a stubborn “arctic outbreak," tacked onto an already cold return to work for many Americans, augurs what meteorologist at AccuWeather.com are calling “the coldest winter in many people’s memory.”
Highs Versus Lows
On the other hand, the National Center for Atmospheric Research in Boulder argues that - while there have been numerous record lows - there have been more record highs than lows in the past decade, and that the ratio of record highs to record lows has actually increased. See this, this, this and this.
Short-Term Aberration, Or Change in Climate Trend?
Are the current spate of record lows just a short-term aberration, or a change in climate trends?
Those defending the C02 global warming theory argue, of course, that short-term weather fluctuations are irrelevant, and that the long-term trend is runaway warming.
But on Tuesday, the New York Times' Andrew Revkin presented a less simplistic yet still mainstream view of the issue:
A big driver of the outbreaks of record cold and snow in many spots around the Northern Hemisphere is ... the Arctic Oscillation, a pattern of atmospheric pressure that has two phases, positive and negative (somewhat like the more familiar cycle of El Niño and La Niña in the Pacific). A strong negative or positive condition can powerfully influence weather around the northern half of the globe and the behavior of sea ice on the Arctic Ocean.
The blue dot shows an extraordinary negative plunge of the index in December, taking it below any such reading since at least 1950 ...
The head of the Beijing Meteorological Bureau asserted that global warming was behind unusual atmospheric patterns (a heap of climate scientists I queried saw no such link). Blogs of those variously called climate realists/skeptics/deniers are hammering on the chilly conditions, presumably in hopes of fending off a new push to close out the climate bill in the Senate.
John Michael Wallace of the University of Washington, one of the climate scientists who first identified the seesaw patterns of pressure around the North Pole and northern mid-latitudes, told me that the steep drop at the moment is likely to be transitory rather than a sign of a new trend in the Northern Hemisphere pressure cycle.
Overall, federal forecasters have said that the warming influence of a persistent El Niño warming of the tropical Pacific Ocean is likely to be a bigger driver of conditions through the full course of this winter ...
Michelle L’Heureux, a meteorologist at the National Oceanic and Atmospheric Administration’s Climate Prediction Center, told me there’s simply no explanation for what drives such extremes in the Arctic Oscillation, which she described as both a potent driver of northern latitude conditions and one of the least predictable, and understood, patterns in the atmosphere.
In other words, the mainstream view is that the Arctic Oscillation is driving the cold whether, no one knows what causes the Arctic Oscillation to switch on or off, but it will likely be short-term.
Top Climate Scientists Disagree
One of the leading climate modelers in the world - Professor Mojib Latif of Germany's Leibniz Institute - disagrees. Professor Latif is the recipient of several international climate-study prizes and a lead author for the United Nations Intergovernmental Panel on Climate Change (IPCC) who has contributed significantly to the IPCC's last two five-year reports that have stated unequivocally that man-made greenhouse emissions are causing the planet to warm dangerously.
Specifically, Latif thinks that the cold temperatures could last a decade or two.
In case you didn't catch it, Latif made a presentation in September which addressed the cooling trend:
Yet last week in Geneva, at the UN's World Climate Conference--an annual gathering of the so-called "scientific consensus" on man-made climate change --Latif conceded the Earth has not warmed for nearly a decade and that we are likely entering "one or even two decades during which temperatures cool."
The global warming theory has been based all along on the idea that the Atlantic and Pacific Oceans would absorb much of the greenhouse warming caused by a rise in man-made carbon dioxide, then they would let off that heat and warm the atmosphere and the land.
But as Latif pointed out, the Atlantic, and particularly the North Atlantic, has been cooling instead. And it looks set to continue a cooling phase for 10 to 20 more years.
"How much?" he wondered before the assembled delegates. "The jury is still out."
And see this.
Latif believes that after several decades of cooling, then global warming will kick in.
Other climate scientists predict longer periods of cooling. For example, Professor Don Easterbrook from Western Washington University says:
The PDO cool mode has replaced the warm mode in the Pacific Ocean, virtually assuring us of about 30 years of global cooling.And professor Qing-Bin Lu University of Waterloo argues in a peer-reviewed paper that we will have 50 years of cooling.
Who Is Right?
So who's right?
I have no idea. But - for now - I'm freezing my tail off.
That raises an interesting question: even if we are projected to have C02-induced global warming in the future, will the current cold snap - if it continues for another year or so - change the long-term climate trend?