Jennifer Marohasy

a forum for the discussion of issues concerning the natural environment

Archives for September 8, 2008

Sea Levels Can’t Rise by MORE than 2 Metres by 2100

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In 2006, in his famous documentary, An Inconvenient Truth, Al Gore claimed sea levels would rise by 20 feet (six metre). 

 

The Intergovernmental Panel on Climate Change (IPCC) is more conservative, suggesting a rise of no more than 0.60m by 2099 in its 2007 report.

 

But in March last year a fellow called Robyn Williams, who has a monopoly on the broadcasting of science programs on Australia’s ABC, scared us with claims sea levels could rise by over 100 metres in the next century because of increases in the rate of ice melt in Greenland and western Antarctica. 

 

A study of sea level rise from ice melt in Greenland and western Antarctica has just been published in Science and concludes that a rise of 0.8 metres is possible by 2100, but MORE** than 2 metres “physically untenable”. 

 

Research scientists W.T. Pfeffer, J.T. Harper and S.O’Neel calculated how much ice and water would need to be lost from Greenland and Antarctica for a two metre rise, then how fast contributing glaciers would need to move in order to dump that much ice, and concluded that a two meter rise in sea level by 2100 would require significantly faster ice velocities than had ever been reported before.

 

Of course at the moment it is unclear how much warming is actually occurring at the Antarctic, with some suggesting a general trend of cooling there in accordance with the recent global trend.  But if the melting starts again at the Antarctic, and continues in the Arctic, it is perhaps reassuring to know, that even under a worst case scenario sea levels should not rise by more than 0.8 metres in the next 100 years. 

 

 

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** I’ve added the word ‘more’ included to the title of this piece as Pfeffer et al claim it is physically untenable to suggest a rise of more than 2 metres – not up to 2 metres as I suggested in the original post.  Thanks to Luke and others for pointing this error out.

 

Kinematic Constraints on Glacier Contributions to 21st-Century Sea-Level Rise, W. T. Pfeffer,  J. T. Harper, S. O’Neel, Science, 5 September 2008:
Vol. 321. no. 5894, pp. 1340 – 1343. DOI: 10.1126/science.1159099

 

I’m in Tokyo

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I arrived in Tokyo yesterday for a meeting of the Mont Pelerin Society. 

My mobile phone is not working, so any messages will go unanswered for at least a week.  If you need to contact me, try email.  

New Otani Japanese Garden, Tokyo
New Otani Japanese Garden, Tokyo

The four pale-coloured elongated images in the pond are fish. The photograph was taken this morning at the New Otani Japanese Garden in Tokyo.

Bill Kininmonth Requests Explanation of the Greenhouse Effect

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Bill Kininmonth knows a lot about climate science, he is a meteorologist and he was the head of Australia’s National Climate Centre from 1986 to 1998.   He is also a well known global warming skeptic and is particularly critical of the idea that the principles for sustaining the greenhouse effect are well understood.   While this may seem like a ridiculous proposition, indeed the greenhouse effect is the underpinning science for the hypothesis of dangerous global warming, in a recent letter to the Federation of Australian Scientists and Technologists (FASTS) he explains how the Intergovernmental Panel on Climate Change (IPCC) are neither consistent in their explanation for the greenhouse effect nor provide a mechanism that accords with the global average earth energy budget.   

 

Mr Kininmonth’s letter to FASTS follows their issuing of a media release on climate change including comment that:

 

“The scientific evidence is compelling that global policy objectives must remain squarely focused on returning greenhouse gas concentrations to near pre-industrial levels through the reduction of emissions.”

 

The media release was accompanied by a statement that included comment:

 

“The physical principles of the greenhouse effect are well-understood. Without greenhouse gases, clouds or aerosols, the surface of the Earth would have a mean temperature of about 18oC below zero. While the natural atmospheric composition varies over time, the observed warming in the late 20th century can be attributed with a very high degree of confidence to additional human emissions of greenhouse gases.

The statement was developed and published without input from rank and file member of FASTS and indeed not everyone agrees that the scientific evidence is compelling.   Mr Kininmonth explains why in the following open letter:

Bradley Smith

Executive Director

Federation of Australian Scientific and Technological Societies

 

Dear Bradley,

 

 

In the “Statement on Climate Change” issued by FASTS on 4 September is included the sentence, ‘The physical principles of the greenhouse effect are well-understood.’

 

I would be grateful if you would provide a summary of the physical principles of the greenhouse effect. In making this request I do not doubt the existence of the greenhouse effect, only that the scientific principles for sustaining the greenhouse effect are well understood.

 

The IPCC, in its most recent (2007) report has the statement (Frequently Asked Question 1.1):

“The reason that the Earth’s surface is this warm (14oC) is the presence of greenhouse gases, which act as a partial blanket for the longwave radiation coming from the surface. This blanketing is known as the natural greenhouse effect.”

 

There are two problems with this statement. Firstly, a blanket acts as an inhibitor of conduction and not radiation; oxygen and nitrogen are equally as good insulators as water vapour and carbon dioxide and adding greenhouse gases does not materially affect the conducting properties of the atmosphere. Secondly, net upward longwave radiation increases with altitude (according to the IPCC global average data, from 66 Wm-2 at the surface to

235 Wm-2 at the top of the atmosphere); the increase is due to the greenhouse gases and can hardly be described as inhibiting (ie, blanketing) radiation loss to space!

 

In an attempt to clarify the situation, the IPCC has an additional explanation (Frequently Asked Question 1.3):

“Much of this thermal radiation emitted by the land and ocean is absorbed by the atmosphere, including clouds, and reradiated back to Earth. This is called the greenhouse effect.”

 

As the IPCC’s global average data clearly show, there is more longwave radiation emitted from the Earth’s surface than is emitted by the atmosphere back to the surface. The net effect of longwave radiation is to cool the Earth’s surface, not to warm it.

 

The above two explanations from the IPCC are quite different and neither accord with the data presented on the global average Earth energy budget. As you will appreciate, the greenhouse effect is the underpinning science for the hypothesis of dangerous global warming from increasing atmospheric carbon dioxide caused by human activities. If we cannot get the underpinning science as a clear and logical construct then the edifice is no more than a house of cards! Also, if it is not possible to explain how the Earth’s greenhouse effect is sustained then how can we be confident that the computer models used to project global warming are adequately representing the greenhouse effect?

 

As FASTS claims that the physical principles of the greenhouse effect are well understood I presume FASTS has a different explanation than what IPCC has presented. I would be grateful for a summary of the FASTS principles of the greenhouse effect.

 

Yours sincerely,

 

 

William Kininmonth

Kew, Victoria

 

As long as institutions and organisations like FASTS demand that governments impose new taxes and regulations on the basis that the science is settled, they must be prepared to publicly engage in discussion on the same.  Indeed I look forward to posting the response from FASTS to Mr Kininmonth’s open letter.

New Banner, Format and Policies for the Blog

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Regular readers of this website will have noticed that since yesterday we have a new blog banner and upgraded blog format.

I am not yet familiar with all the new gadgets, widgets, asides and facilities that come with the new format and I am still to add links and develop comment policy settings. So, please be patient, there are more changes to come.

A redesign like this doesn’t just happen.  I would like to thank Chris for the new banner and Dewi for the tedious transfer from moveable type to wordpress. If you want a new website or blog you might consider the team at www.internet-thinking.com.au  headed by Graham Young.  They also publish www.onlineopinion.com.au.

The new banner is from a photograph of an escarpment in the Blue Mountains that I took in December 2007.  An uplifting about 200 million years ago was followed by erosion exposing layers of sedimentary rock.  Superimposed on this is new vegetation after what was a devastating bushfire in November 2006. Also shown in the picture is a staircase and interestingly Charles Darwin visited this site in January 1836.

Along with the new banner and format I am planning other changes.  I’ve tried to make this blog a gathering place for people with a common interest in environmental issues, to strive for tolerance and respect and to give different perspectives an opportunity to be heard. This necessarily involves tolerating what many would consider offensive ideas; indeed it is increasingly easy to offend when you take an evidence-based approach to many emotive environmental issues including whaling and climate change.

While I don’t have a problem with what some would consider offensive ideas, I do have a problem with offensive behaviour in particular language that is designed to be personal and derogatory while not progressing understanding.

So, with the new upgraded format, I hope we can lift the standard of commentary.  

Many thanks to all those who have contributed to this blog over the last three years; particularly Paul Biggs and Neil Hewett who have made a really significant contribution over the last year. Paul will have a new blog up soon and I will have links to his blog and also Neil’s established blog soon.

Cheers,