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March 23, 2012


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Michael- well summarized.. OnPointRadio had a discussion on this topic of building near the coast - http://onpoint.wbur.org/2012/03/19/rising-tides. building near coasts is just not being discouraged, not just by real estate developers but by government policy as well..

Suvrat - thanks. This link is to a great radio report, including an interview with Ben Strauss,who participates for the entire program, and really compelling commentary from a variety of people, including on the insurance aspects of these issues. A must-listen-to program.

Michael, did the original report mention any impact on sea-level in NC of the effect of isostatic rebound following the last Ice Age? I suspect that the NC coast would still be sinking as the vast area of Canada freed from ice continues to rise. Also, considering how slowly water is warmed by the air above it, I doubt that the 0.7 deg rise in "average" temperatures since 1850 has had much to do with changing sea levels. Unless, of course, the oceans have warmed following the Little Ice Age, thereby causing the rise in air temperatures. Water is warmed much more by direct sunlight. Didn't the sun have a Grand Maximum for most of the 20th Century? None of this is to say that NC planners should ignore the risks of rising seas, simply that any human produced CO2 has stuff-all to do with it. Never forget that we get all our energy from the sun.
Love your blog. Does your financial security require belief in the AGW scam?

Ray, thanks for the long and thoughtful comment!

There are a few things to address here, so I'll try to take them one at a time. First of all, of course, "sea level" is a complex phenomenon, and the equation includes a large number of variables. Therefore, there are two kinds of SL measurement components, one the global or eustatic SL that reflects the volume of the earth's ocean basins and the total volume of the water in them; this is affected by climate, the amount of water locked up in land-bound ice, global temperatures,the rate at which mid-ocean ridges are spreading (and therefore the volumes they take up), and a whole host of other, global-scale factors. Then, for any place on any coast, there's the local relative SL rate of change. The big eustatic signal is overprinted by local geological events, subsidence and uplift that can be caused by tectonics, melting or advancing ice sheets, withdrawal of groundwater etc. It's clearly this local relative SL rise that is of relevance to local communities and planners.

Now, the effect of receding ice sheets is very apparent on the entire east coast of North America, and it's not simple. As the ice retreated and because the earth's crust is like an elastic beam, there is a moving bulge in front of the ice, with an associated moving depression. So relative SL will change in a given location depending on where it is relative to this migrating bulge/depression. The history of this has been documented for the Atlantic Coast (see http://pubs.giss.nasa.gov/docs/1990/1990_Gornitz_Seeber.pdf). For North Carolina, changes were large from 10,000 to 5,000 years ago, but for the last 2,500 years the changes have been small. Most (but certainly not all) SL change has been the result of eustatic SL rise and local effects such as the withdrawal of groundwater and the consequent subsidence. The CRC report contains the following statement: "The cumulative data from these four investigations indicate that RSL change varies as a function of latitude along the NC coast, with higher rates of rise in the north, and lesser rates of rise in the south. This is a function of the local geology as well as differential crustal subsidence and uplift."

Most of the 0.7 degree rise has taken place very recently, and even a small temperature increase of the oceans, given their volume AND the vast areas of "land" that lie close to SL, will cause a measurable increase in eustatic SL. Solar maxima? Yes, they are a factor, but it doesn't seem that the twentieth century was particularly extreme (see http://www.nasa.gov/mission_pages/sunearth/news/solarcycle-primer.html and http://www.swpc.noaa.gov/info/SolarMax.pdf) or at least, not sufficient to account for the documented changes.But I'm open to discussion of this - it's certainly not my area of expertise.

You're right, of course, we get all of our energy from the sun. But this is not a "real time" extraction - in using fossil fuels, we are harvesting the sun's energy from long periods of the planet's past.

But my point here (and in other related rants) is, like yours (but perhaps coming from a slightly different place) that communities and planners need only pay attention to the documented, measured, scientific, facts of SL rise, not the causes (about which they can do very little).

I'm glad you like the blog! And to answer your final question, I am determined that it be a place for debate around issues that relate (however loosely) to its theme, and topics about which I like to think that I am qualified to talk. For this reason, I have intentionally avoided the anthropogenic global warming issue (sorry, but I prefer that word to "scam"). My financial security has nothing to do with my position on how I manage my blog and its topics, or, indeed, what I believe.

But I'm always open to continuing this conversation!

Thanks again.

Michael, Thank you for the detailed reply to my comments. My apologies for the gratuitous attack on your motivation for the post. Yes, sea level is very complicated. Unfortunately, discussion of it in the public sphere has been badly damaged by the alarming predictions made by the IPCC. Those predictions are based solely on huge & unwieldy computer programs, which attempt to recreate climate trends from the recent past, then extrapolate those trends into the future. Sadly, there are no quality control provisions in place to ensure the data fed into these programs is handled correctly. Nor do the programs creators allow independent verification of their millions of lines of code, which means people like me do not trust their results.

Ray - thanks for continuing the conversation. And you know what? In many ways I agree with you. We seem to think that models are miniature, algorithmic, versions of reality with powers and certainty unsupported by the way they work and the assumptions that went into them. For some time, I have treasured a couple of quotations from eminent physicists, the first from Werner Heisenberg:

"We have to remember that what we observe is not nature in itself, but nature exposed to our method of questioning."

The second is from Per Bak:

"Sometimes we feel that our modeling of the world is so good that we are seduced into believing that our computer contains a copy of the real world, so that real experiments or observations are unnecessary."

There is absolutely nothing wrong with models, they are powerful tools. As long as we recognise and document their limitations and the uncertainty associated with their outputs, and don't pervert them for axe-grinding.

Professionally, I am intimately familiar with dealing with uncertainty - and I find it fascinating and stimulating: a certain world would be an excrutiatingly boring place in which to live (and there, of course, thrives science). The problem comes, as you say, when that intrinsic uncertainty is ignored or manipulated in the media (largely through ignorance) and when science provides the media and the public with little help in coming to grips with it. Science becomes politicised.

In my view, there is nothing intrinsically wrong with the models used by climate scientists, or the work of the IPCC. BUT the conclusions drawn from them are over-simplified, melodramatic. And yet they don't need to be. The science of atmospheric greenhouse gases is indisputable - and our pouring huge volumes of those gases into our atmosphere simply seems like a stupid (and somewhat selfish)thing to do. The exact numbers and the reliability of predictions is open to debate, but the activity is, as I said, stupid.

That is not to say that I subscribe to any kind of Gaia theory - as a geologist, to think that our planet in any way "cares" about our existence, or that the planet's future depends on what we, motes of dust on its scale, do, would be nonsense.

My interest in uncertainty, its key role in science, and its misrepresentation in the public domain, led me to kick off a session at a Google "unconference" a couple of years ago. You can find a post or two on this back in the archives of the blog, but the interesting point here is that, in the process of this, I got to meet Judith Curry. Judith is a serious atmospheric and climate scientist at Georgia Tech, and she shares my views on the failure of climate science to describe properly the uncertainties. As a result, she has been vilified by a signficant segment of the "climate science community" but, at the same time, commands enormous respect in other segments. She keeps a very compelling blog at Climate Etc., http://judithcurry.com/. I recommend it, and I think you would find it interesting.

Judith is not a "sceptic," but she simply wants to see the science done, and described, correctly, with the conclusions properly portrayed for anyone who is interested - or should be.

Special difficulties arise when science bears strongly on public policy and business practices, as for decades public policy and business practices have borne strongly on science, through research money and otherwise. The only scientific discipline for studying that intersection is sociology, itself barely beyond descriptive reports. (For the claim made by economics to scientific status, see http://www.gresham.ac.uk/lectures-and-events/greshams-law-in-economics-background-to-the-crisis
or look about you. Economics cannot explain why flood insurance--without which the beaches would be empty--although obviously unprofitable for insurance companies, should be taken on by the US government.)
Personally, I find the risks involved in possible climate change significant enough that I would like to see public policy stop or at least slow the digging of what could be a very big hole, while the data and the science grow more robust.
Personally, however, I doubt that the immediate needs and desires of 7 billion people will allow long-term risk, even if scientifically demonstrated, to limit short-term behavior, in public policy or in business practice. To hope otherwise, I fear, is to hope that intelligent design will prevail over evolution.
"Faced with the choice between changing one's mind and proving that there is no need to do so, almost everyone gets busy on the proof."--John Kenneth Galbraith
As the businessman said to the sociologist, "And yet there is a great deal of money made here, good morning, sir."

The natural disasters we are experiencing nowadays can be considered as the wraths of nature due to man's deeds. These could be effects of climate change. Flash floods, storm surge, typhoon and the like are some of them. SO, in order to mitigate the effects of these, we should find ways how to adopt climate change and government officials as well as every individual should find ways to protect the lives of the common people.

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