The conventional wisdom asserts that climate change increases the frequency and/or severity of extreme weather events. It's entirely unproven. And, it's possible that the Intergovernmental Panel on Climate Change (IPCC) itself may be backing-off the claim, according to the BBC's Richard Black, who has a leaked copy of the forthcoming IPCC "extremes" report [note: full report released]:
The draft, which has found its way into my possession, contains a lot more unknowns than knowns.Of course, other journalists read the draft exactly opposite. Despite the fact that the death rate from extreme weather had dropped dramatically.
On the one hand, it says it is "very likely" that the incidence of cold days and nights has gone down and the incidence of warm days and nights has risen globally.
And the human and financial toll of extreme weather events has risen.
But when you get down to specifics, the academic consensus is far less certain.
There is "low confidence" that tropical cyclones have become more frequent, "limited-to-medium evidence available" to assess whether climatic factors have changed the frequency of floods, and "low confidence" on a global scale even on whether the frequency has risen or fallen.
In terms of attribution of trends to rising greenhouse gas concentrations, the uncertainties continue.
While it is "likely" that anthropogenic influences are behind the changes in cold days and warm days, there is only "medium confidence" that they are behind changes in extreme rainfall events, and "low confidence" in attributing any changes in tropical cyclone activity to greenhouse gas emissions or anything else humanity has done.
(These terms have specific meanings in IPCC-speak, with "very likely" meaning 90-100% and "likely" 66-100%, for example.)
And for the future, the draft gives even less succour to those seeking here a new mandate for urgent action on greenhouse gas emissions, declaring: "Uncertainty in the sign of projected changes in climate extremes over the coming two to three decades is relatively large because climate change signals are expected to be relatively small compared to natural climate variability".
So what's the timeline for climate change action? Earlier this month, a different UN agency said climate change would be irreversible within five years. Back in 2006, we had 30 years. Just two years ago, alarmists gave the planet 10 years. Yet global surface temperature measurements flatlined since 2000. (And, of course, a general warming trend likely would increase agricultural production in some regions.)
Does that mean we have until 2016? Or 2021? Or 2051? As David Whitehouse says:
Even making the questionable assumption that our computer models are good enough to predict what will happen in the future, for projected changes by the end of the 21st century, the uncertainties in those computer models, and the range of natural climatic variability, are far larger than any predicted human-influenced effects.In the real world, there won't be global consensus on extending the Kyoto emissions limits. In any event -- as I've always said -- climate change is all about the cash: an attempt to mandate transfer payments from the developed to the developing world.
The Australian agrees. And, according to the humanitarian charity DARA, only eight percent of the finance for climate change actions in developing countries has been disbursed. Whether this reflects inefficiency or corruption, the point is that mere wealth transfers aren't the answer.
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In early 2009, NASA's Dr James Hansen said we had only four years to save the earth from climate change. Of course, he may have been paid to say that.