Archives for April 2008

One of the most influential scientists behind the theory that global warming has intensified recent hurricane activity says he will reconsider his stand.

The hurricane expert, Kerry Emanuel of the Massachusetts Institute of Technology, unveiled a novel technique for predicting future hurricane activity this week. The new work suggests that, even in a dramatically warming world, hurricane frequency and intensity may not substantially rise during the next two centuries.

Read more in the Houston Chronicle: Hurricane expert reconsiders global warming’s impact

The peer reviewed BMAS article is available on Kerry Emanuel’s homepage here.

This is another blow to climate alarmists and Gore’s AIT, where the ‘science’ is presented as being ‘settled.’

Let’s see if the mainstream media report on this and if the BBC can post a website article unmolested by ‘climate campiagner’ Jo Abbess.

Biological productivity controls cloud formation and may be the lever that caused supergreenhouse episodes during the Cretaceous and Eocene, according to Penn State paleoclimatologists.

“Our motivation was the inability of climate models to reproduce the climate of the supergreenhouse episodes of the Cretaceous and Eocene adequately,” said Lee R. Kump, professor of geosciences. “People have tried increasing carbon dioxide in the models to explain the warming, but there are limits to the amounts that can be added because the existing proxies for carbon dioxide do not show such large amounts.”

In general, the proxies indicate that the Cretaceous and Eocene atmosphere never exceeded four times the current carbon dioxide level, which is not enough for the models to create supergreenhouse conditions. Some researchers have tried increasing the amount of methane, another greenhouse gas, but there are no proxies for methane. Another approach is to assume that ocean currents changed, but while researchers can insert new current information into the models, they cannot get the models to create these ocean current scenarios.

Kump and David Pollard, senior research associate, Earth and Environmental Systems Institute, looked for another way to create a world where mean annual temperatures in the tropics were above 100 degrees Fahrenheit and polar temperatures were in the 50-degree Fahrenheit range. Changing the Earth’s albedo — the amount of sunlight reflected into space – by changing cloud cover will produce supergreenhouse events, the researchers report in today’s (April 11) issue of Science.

“The model reduces cloud cover from about 64 percent to 55 percent which lets in a large amount of direct sunlight,” Kump says. “The increased breaks in the clouds, fewer clouds and less reflective clouds produced the amount of warming we were looking for.”

EurekAlert: Absence of clouds caused pre-human supergreenhouse periods

National Geographic: Lack of Clouds Amplified Dino-Era Warming, Study Says

Abstract:

Amplification of Cretaceous Warmth by Biological Cloud Feedbacks

Lee R. Kump1* and David Pollard2

The extreme warmth of particular intervals of geologic history cannot be simulated with climate models, which are constrained by the geologic proxy record to relatively modest increases in atmospheric carbon dioxide levels. Recent recognition that biological productivity controls the abundance of cloud condensation nuclei (CCN) in the unpolluted atmosphere provides a solution to this problem. Our climate simulations show that reduced biological productivity (low CCN abundance) provides a substantial amplification of CO2-induced warming by reducing cloud lifetimes and reflectivity. If the stress of elevated temperatures did indeed suppress marine and terrestrial ecosystems during these times, this long-standing climate enigma may be solved.

1 Department of Geosciences and Earth System Science Center, Pennsylvania State University, University Park, PA 16802, USA.
2 Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA.

The April edition of Birmingham University’s newsletter BUZZ incudes comment from climate researcher Chris Kidd that,

“Despite these warmer temperatures and recent news of further ice-shelf melting, global temperatures do appear to be cooling after reaching a peak in 1998.

Since then the temperatures steadied and have fallen over the past couple of years: in fact, Antarctica saw its greatest recorded extent of ice in 2007, unlike the dwindling Arctic sea ice.

As for the summer, seasonal forecasting is best left to computer models to get wrong, but it would seem that we could be in for an ‘average’ summer: cool and showery.”

Let’s hope Jo Abbess, the activist who recently insisted the BBC change a story that mentioned some global cooling, doesn’t try and get this article changed!

———————–
Dr Chris Kidd is from the Climate and Atmospheric Research Group, in the School of Geography, Earth and Environmental Sciences, University of Birmingham, and he is not a climate skeptic.

At the time of writing the April Edition was not yet available online.

This Story was edited by Jennifer at 9.30am on April 10.

There is an amusing you-tube clip with Americans Noel Sheppard and Glenn Beck talking about the BBC and how quickly and convincingly environment reporter Richard Harrabin caved to environmental activist Jo Abbess.

Have a look:

http://youtube.com/watch?v=216v5AoQcFQ

Apparently the BBC is refusing to comment on the Jo Abbess fiasco.

RESPECTED academic Don Aitkin has seen the ugly side of the climate change debate after being warned he faced demonisation if he challenged the accepted wisdom that global warming poses a danger to humanity.

Professor Aitkin told The Australian yesterday he had been told he was “out of his mind” by some in the media after writing that the science of global warming “doesn’t seem to stack up”.

Declaring global warming might not be such an important issue, Professor Aitkin argued in a speech to the Planning Insitute of Australia this month that counter measures such as carbon trading were likely to be unnecessary, expensive and futile without stronger evidence of a crisis.

The eminent historian and political scientist said in a speech called A Cool Look at Global Warming, which has received little public attention, that he was urged not to express his contrary views to orthodox thinking because he would be demonised.

He says critics who question the impact of global warming are commonly ignored or attacked because “scientist activists” from a quasi-religious movement have spread a flawed message that “the science is settled” and “the debate is over”.

Professor Aitkin is a former vice-chancellor at the University of Canberra, foundation chairman of the Australian Research Council and a distinguished researcher at the Australian National University and Macquarie University…

According to the professor, much of the inadequate policy-making on climate change is based on “over-certainty in the absence of convincing argument and data” and “over-reliance on computer models”.

“While governments can never ignore what they see as popular feeling, good policy cannot be based on moods,” he says.

Read more here: http://www.theaustralian.news.com.au/story/0,,23509775-2702,00.html?from=public_rss