September 8, 2009

Global Warming On Hold. Again.

FROM-South Dakota Politics

I have never thought of myself as much of a global warming skeptic (not that there's anything wrong with that!). I have over several years of following the issue, mostly accepted the following propositions:

The world has been in a long term warming trend; and

Human activities are contributing to that warming.

Of course the devil is in the qualifications: whether the trend continues, and how much effect we have. I still hold to number one, but number two has become rather less certain as more research comes online. Weather is the textbook case of a chaotic system, and that means that precise determinations are impossible.

I have also believed in these propositions:

1. We don't know whether further warming will be good or bad on the whole.

2. We just aren't going to do anything significant to arrest the human activities that are said to be driving global warming.

3. The only practical policies are those that are directed toward dealing with climate change, whatever it may be.
Well, number one is addressed in a recent piece in The New Scientist:

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.

Now in fact, standard readings of global climate change has been flat or cooling for over a decade. But never mind that. Here is someone who knows his stuff and expects cooling for the next two decades. Now two decades of cooling is a blip on the screen in the long term, but this contradicts everything that we have been told to expect. Did any of the climate projection models project it?

"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."

… 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.

I like those bits about "nasty questions" and "climate-change orthodoxy." In case you are wondering, nasty questions are precisely those that challenge an orthodoxy.

In fact, this undermines the case for anthropogenic global warming over recent decades, which is pretty much the entire case for AGW. And then there is this:

Another favourite climate nostrum was upturned when [Vicky] Pope [from the UK Met Office] 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.

Remember all those frightening stories about ice sheets melting and San Francisco drowning and how it was all our fault? Well, apparently they aren't, and probably it isn't.

And you can't help but love that bit about model biases. The climate change legislation in Europe and Cap and Trade in Congress are based entirely on climate change models. There is no reason any sane person should have such confidence in those models.

The world is unusually warm right now. That is a very good thing. Most of the history of this ball of dirt has been a rather nastier story. We are overdue for an ice age. I will worry about that after the health care bills go down.

There are sensible reasons to be concerned about the effect of human activity on the global climate. The Al Gore Global Warming Orthodoxy has nothing to do with that.


No comments:

Post a Comment