Monthly Archives: March 2011

Climate Science

Minchin’s junk science

261 Comments

Articles like this give the impression that climate change doubters and believers talk from two legitimate but different scientific frames of reference.

Wrong!

Roy Spencer is one of the main proponents paid as an academic scientist who claims that the human effect on climate is negligible. Barry Bickmore of Brigham Young University critically analyses Spencer’s position. In a 2008 paper:

Spencer was only able to obtain this result by assuming unrealistic values for various model parameters. If realistic values are used, the effect Spencer described is negligible.

Then in later work Spencer “claims to show with his simple climate model that, not only is climate sensitivity low, but most of the global warming in the 20th century can be explained by a natural cycle called the Pacific Decadal Oscillation.”

I took apart Spencer’s climate model, programmed it into my computer, and showed that, once again, he was only able to come to his conclusions because he was willing to use absurd values for some of his model parameters. Furthermore, he used a bizarre statistical technique that he apparently just made up, because it was capable of giving him nearly any answer he wanted.

Continue reading Minchin’s junk science →

Climate Policy & Planning, Climate Science

Climate clippings 21

34 Comments

These posts include a brief mention of a number of news items relating to climate change. They don’t preclude treating any of these topics at more length in a separate post.

They can also serve as an open thread so that we can keep each other informed on important climate news.

Mega-heatwaves in Europe

Mega-heatwaves like the one in 2003 will become five to 10 times more likely by 2050 according to a recent study, occurring at least once a decade. The 2010 heatwave was something else again.

But the 2010 heatwave was so extreme – 10C above the average for the first week of August between 1970 and 2000 – that similar events are only expected to occur once every 30 years or so.

The 2010 event caused some 50,000 deaths, reduced the Russian grain crop by 25% and cost the nation $15 billion. It should be noted that the link between that event and climate change as such has not yet been established, but the incidence of mega-droughts is expected to increase nevertheless. Continue reading Climate clippings 21 →

Climate Science

Climate clippings 20

57 Comments

These posts include a brief mention of a number of news items relating to climate change. They don’t preclude treating any of these topics at more length in a separate post.

They can also serve as an open thread so that we can keep each other informed on important climate news.

Nicholas Stern: Climate inaction risks a “global war”

Climate Progress has the story:

The temperature increases, the temperature changes of this kind, transform where people can be. In the upwards direction, you’re going to get some areas that become deserts, probably most of southern Europe. Others that are inundated: Florida, Bangladesh, and so on.

What we’re talking about here — this the cost of inaction, the cost of not doing much — is a transformation of where we can be. Over a hundred, 120 years, we can’t be that precise, a serious risk of global war, really, because you’ve got hundreds of millions of people, perhaps billions of people moving. That’s the cost of inaction. It’s potentially immense.

It should be noted that Stern is not a security analyst, but Gwynne Dyer who is told us three years ago that security establishments were gaming scenarios where they saw mass migration due to climate change. And troubles over major river systems, like the Nile, the Mekong, the Tigris and Euphrates, and the numerous rivers on which Pakistan depends. Continue reading Climate clippings 20 →

Climate Science

Immodest perturbation

55 Comments

Incurious and Unread in this comment talked about a “modest perturbation” and positive and negative feedbacks:

I can’t help feel that Gaia is letting us down here. It seems that we keep on getting positive feedback effects on the climate rather than negative feedback.

That seems kind of odd. As I understand it, the climate has been fairly stable pre-AGW, which suggests that negative feedback effects dominated. We have what seems to me (probably in my ignorance) a modest perturbation and suddenly we are envisaging positive feedback and an uncontrollable excursion to a new Venusian equilibrium.

Is it just that it is the positive feedback stories which hit the headlines, or is there some underlying reason why there are more positive feedback than negative feedback effects?

First up, it’s forcings that change the temperature positively or negatively. Forcings are amplified by feedbacks, positive and negative. For a stable climate the net effect of forcings and feedbacks should be zero, they should cancel each other out. Continue reading Immodest perturbation →

Climate Policy & Planning, Climate Science

Climate clippings 19

135 Comments

These posts include a brief mention of a number of news items relating to climate change. They don’t preclude treating any of these topics at more length in a separate post.

They can also serve as an open thread so that we can keep each other informed on important climate news.

Garnaut Update Paper 5: The science of climate change

Garnaut’s series of update papers has now reached Update Paper 5: The science of climate change. This is worth a longer look, but suffice it to say here that the sense of urgency has grown considerably.

  • Observable trends seem to be running ahead of predictions.
  • The 2C limit looks high and may in fact represent the boundary between dangerous climate change and extremely dangerous climate change.
  • 450 ppm looks high, but we are going to shoot through it.
  • Garnaut has picked up on the “emissions budget” approach I have been banging on about. On present trends we (the world) will use up our remaining budget of allowable emissions in a couple of decades.

Continue reading Climate clippings 19 →

Climate Science

Climate opinion surveys – a cautionary tale

67 Comments

University of Michigan psychologist Jonathon Schuldt led a study which asked this question:

“You may have heard about the idea that the world’s temperature may have been going up over the past 100 years, a phenomenon sometimes called ‘global warming.’ What is your personal opinion regarding whether or not this has been happening?”

People were asked to respond on a seven-point scale, from “Definitely has not been happening” to “Definitely has been happening.” They were also asked to identify their political allegiance.

Turns out 86.9% of Democrats endorsed global warming, whereas only 44% of Republicans did. Continue reading Climate opinion surveys – a cautionary tale →

Climate Science

Climate clippings 18

84 Comments

These posts include a brief mention of a number of news items relating to climate change. They don’t preclude treating any of these topics at more length in a separate post.

They can also serve as an open thread so that we can keep each other informed on important climate news.

China puts climate above reckless growth

Prime Minister Wen Jiabao:

“We must not any longer sacrifice the environment for the sake of rapid growth and reckless roll-outs, as that would result in unsustainable growth featuring industrial overcapacity and intensive resource consumption.”

China’s environment minister on Monday issued an unusually stark warning about the effects of unbridled development on the country’s air, water and soil, saying the nation’s current path could stifle long-term economic growth and feed social instability.

We need them over here to talk to HM Opposition. Continue reading Climate clippings 18 →