Unnatural Hazards

Christine Shepard has recently published her first peer-reviewed paper as lead author, Assessing future risk: quantifying the effects of sea level rise on storm surge risk for the southern shores of Long Island, New York (Shepard et al. 2012, Nat. Hazards, 60:727–745 DOI 10.1007/s11069-011-0046-8). Such a first is usually (and it should be) a moment of triumph for a young scientist.

But because her research involves the risk of sea level rise, and because that rise is linked to global warming, Shepard’s work has come under fire — not for its results, but simply for using a reasonable result from the research of others. The paper does just what the title says: studies the impact of sea level rise on storm surge risk in Long Island, and the abstract summarizes the result:

We find that even modest and probable sea level rise (.5 m by 2080) vastly increases the numbers of people (47% increase) and property loss (73% increase) impacted by storm surge.

The whole thing is pretty non-controversial. Sea level rise of half a meter or more is supported by quite a bit of scientific literature (Rahmstorf 2007, Vermeer and Rahmstorf 2009, Grinsted et al. 2010, Nicholls and Cazenave 2010), in fact there’s reason to believe it may be a lot greater. But Shepard et al. isn’t about how much sea level will rise. It’s about what will happen to Long Island if it does.

If you disagree with the sea level forecast, take it up with Rahmstorf and Vermeer and Grinsted and Nicholls and Cazenave.

Unfortunately, the editor of the journal Natural Hazards, Tad Murty, has described global warming as “the biggest scientific hoax being perpetrated on humanity.” He’s one of the authors of “Independent Summary for Policymakers IPCC Fourth Assessment Report” from ultra-conservative “think tank” the Fraser Institute. The report is so outlandish, it claims such things as “Arctic sea ice showed an abrupt loss in thickness prior to the 1990s, and the loss stopped shortly thereafter.Remind you of anything?.

That may be why Shepard et al. generated so many comments in the journal — three (so far) — and it may be why the comments were published in spite of clear indications of faulty science. Did I say “faulty”? I meant “the absence of.”

There’s a common theme to all three comments: that sea level hasn’t accelerated over the last century or so, so the models used for forecasting are wrong, and that the only acceptable projection to use is the linear trend from the available past data. Does that remind you of the idiotic legislation proposed in North Carolina? The bill that was pushed by “NC-20,” an economic development group? It should. The first comment came from David Burton, who just happens to be on the board of directors of NC-20. The other comments come from A. Boretti and Albert Parker, Australians who specialize in … internal combustion engines.

The argument has four severe problems.

First, sea level rise has accelerated over the last century or so. Although that’s the overall pattern, in detail it has shown a complex pattern of accelerations and decelerations, something which Burton, Boretti, and Parker seem to be blissfully unaware of.

Second, there is good reason to expect dramatic acceleration throughout the 21st century, based on something we like to call “physics.”

Third, when it comes to time series, anyone who knows the difference between a sphincter and a hole in the ground also knows that for complex physical processes, making a long-range forecast by extrapolating a simple trend far into the future is a fool’s errand.

Fourth, perhaps the most severe and most glaring problem with the arguments of Burton and Boretti and Parker and their ilk is that it’s predicated on a false premise: that sea level rise must have accelerated in the last century or so or all the models used for forecasting are wrong. It’s also predicated on the childish notion that the over last century or so, sea level must have accelerated consistently rather than show a complex pattern of changes which the best models (based on something we like to call “physics”) are in good agreement with. Their argument shows the lack of comprehension — nay, the outright rejection — of the complexity and subtlety of the very phenomenon of sea level change.

There’s not a word about changes of land ice in Greenland and Antarctica, or of Alpine glaciers, or the thermal expansion of seawater and the impact of much greater temperature increase throughout the 21st century. There’s no consideration of the fluctuations induced by constant back-and-forth movement of water between land and sea (witness the tremendous transfer of water to the continents in recent mega-flooding events, a process confirmed by the results of the GRACE satellite mission). There’s no understanding of, or apparently even knowledge of, the variety of time scales on which sea level can change, the ubiquitous decadal fluctuations which invalidate a simplistic view of how sea level is changing. Instead, we are confronted with the simpleton’s attitude — that if sea level hasn’t continuously risen at an ever-increasing rate, then all the models are wrong and the impact of global warming is not a problem. It’s just as naive as the idea that we could project the future by extrapolating a simple trend line on time scales of a century or more. Expecting any shred of nuance, or heaven forbid, complexity is asking too much of them. Seriously, you could get more sophistication from a bright middle-school student’s science report.

Furthermore they fail to mention, and apparently to comprehend, that in the last century-and-a-half or so sea level has both accelerated and decelerated. This is no way contradicts what we expect from global warming; the idea that “it must be ever accelerating” which so permeates the comments betrays complete ignorance, even disdain, for the complexity of reality. Tectonic shifts, the natural hydrological cycle, significant human impact on the hydrological cycle, and yes even global warming, can create a much richer and more varied response than they seem able to wrap their minds around. But Burton, Boretti, and Parker have a serious case of “Bastardi’s disease” — if reality is even the least bit complicated, if it can’t be summed up in a 10-second (or less) sound bite, if it involves any amount of “take some time and think about that before moving on” effort, it seems too much for them.

David Burton’s comment on the Shepard et al. paper begins thus:

At its western tip, Long Island meets Manhattan Island, at a place called The Battery. There is an excellent GLOSS-LTT tide gauge there which has been measuring sea levels since 1856.

Due to local land subsidence, sea level is rising faster at The Battery than at 85% of the other GLOSS-LTT tide gauges in the world, but the rate of rise has been nearly constant for over a century, at 2.77 +/- 0.09 mm/year (95% confidence interval).

About 32 Km away, at Kings Point, on the north shore of Long Island, there’s another good GLOSS-LTT tide gauge, which has been measuring sea level since 1931. Sea level there has been rising at only 2.35 +/- 0.24 mm/year.

Despite over 2/3 century of major anthropogenic CO2 emissions, these tide gauges have measured no statistically significant increase in the rate of sea level rise.

It’s the opening salvo of the “sea level hasn’t risen at an ever-increasing rate so all the models are wrong and the impact of global warming is not a problem” meme. And it isn’t even right.

As at most locations, sea level data from New York (the Battery) shows an annual cycle superimposed on any trend present. The first thing to do is remove the annual cycle to compute anomaly rather than raw data. Then we’re better able to estimate the linear trend, and to look for possible changes in the trend. The graph, which is from NOAA, already has the seasonal cycle removed.

If we fit a quadratic trend to the anomaly data, or equivalently remove the linear trend from the anomaly data (to clarify the changes visually) then fit a quadratic trend, we find overall acceleration.

Is that acceleration statistically significant? Why, yes it is, at greater than 99% confidence. Yes, I accounted for autocorrelation in the analysis. Burton’s claim that there has been no acceleration of sea level rise in this tide gauge record is false.

We can even compute the linear trend for different time spans. Here it is, together with its 2-sigma (about 95% confidence) uncertainty range, for time spans ending with the final data values but starting with each year from 1856 through 1990:

Note that the recent trend is faster than the “linear trend of the entire time span.” A lot faster. And the increase, once again, is statistically significant. It puts the lie to Burton’s claim that “the rate of rise has been nearly constant for over a century.” No. It hasn’t.

Why didn’t Burton mention any of these facts? Did he botch the analysis of data from the Battery? I suspect that he simply didn’t do any. In fact I’m rather confident in that conclusion, because the linear trend rate he quotes in the text is the one straight off the NOAA graph, 2.77 mm/yr. But if you look at the text below the graph you’ll note that the given trend is based only on the data through 2006, but the available data go up to December 2011. The linear trend rate including the most recent data is 2.83.

All Burton did was show a graph — which he didn’t even produce himself — and make a false claim based on no analysis. This isn’t so much faulty science as it is the absence of science.

Characterizing changes in sea level rise only by looking at a quadratic fit amounts to assuming constant acceleration, so it’s an extremly crude way to study the issue. The best you can hope for is a rough indication of the long-term pattern, and even that is all too easily obscured by the high noise level in the data. If we compute a lowess smooth of the detrended anomalies, we can see that the pattern of changes has actually been quite complex:

Plotting the smooth alone shows just how extreme are the changes:

It also shows just how rapid has been the most recent sea level rise in New York, and again puts the lie to Burton’s claim that “the rate of rise has been nearly constant for over a century.” No. It hasn’t.

Rather than attempt to take anything like a nuanced view of sea level changes, Burton chooses to wallow in the simpleton’s view by referring to this:

The same thing is true at most other tide gauges around the world. In fact, the best and most comprehensive analyses of sea level measured by tide gauges around the world show slight decelerations in the rate of sea level rise over the last 80 years. [Houston, J.R. and Dean, R.G., 2011. "Sea-Level Acceleration Based on U.S. Tide Gauges and Extensions of Previous Global-Gauge Analyses." Journal of Coastal Research, 27(3), 409–417, DOI:10.2112/JCOASTRES-D-10-00157.1]

Houston & Dean? Yes, that paper. In my opinion it’s one of the worst travesties to appear in the scientific literature, and as long as Burton maintains that it’s among “the best and most comprehensive analyses,” his credibility goes down the toilet along with the Houston & Dean paper.

Burton does discusses the global data sets based on combining tide gauge data from Church & White (the most up-to-date is described here). His exposition is a how-to guide for cherry-pickin’. IF you use a selected version of the Church & White data (not the most recent version), and IF you carefully cherry-pick your start year, then you can claim the absence of acceleration.

If you want to know how cherry it is to use a start year selected for its result, and how it affects the statistics, then read this. Carefully.

Here’s the latest global sea level dataset based on tide gauge data from Church & White (2011):

When looking for acceleration, greater visual clarity results from subtracting a linear fit from the data, then plotting the residuals — often called “de-trended” data but more precisely “linearly de-trended.” Here they are:

Yes, it has accelerated. And decelerated. Several times. The overall pattern is one of acceleration — and the most recent decades show the fastest rise of all

Let’s again compute the linear trend rate for time spans starting with all possible years and ending with the present day. I’ll insist on at least 10 years of data, so here are the rates for all start years from 1880 through 2000 (error bars are 2-sigma and compensated for autocorrelation):

Note that the recent trend is much faster than the “linear trend of the entire time span.” About twice as fast. The “faster than” is statistically significant. In fact the most recent central estimate of the trend in the Church and White data is about equal to the recent trend in satellite data — around 3 mm/yr, compared to the overall trend of 1.5 mm/yr. Imagine that.

By the way, those who are interested in acceleration of sea level rise on longer (millenial) time scales, as well as some of the further complexities regarding future sea level rise, may enjoy this presentation by Jerry Mitrovica.

Clearly, Burton’s claim that sea level rise has not shown acceleration is just plain wrong. Yet he so easily convinced himself of it, and in my opinion there’s a simple explanation — he doesn’t want it to be true. His interest is in economic development, and any inconvenient scientific truth which threatens to increase the cost of that development isn’t allowed to be true. Evidence or not.

We’re interested in actual science, so let’s look closely at the smoothed version of the linearly detrended Church & White data:

The overall (century-long) pattern is acceleration, plain and simple. But on decadal and even multi-decadal time scales, the data show both acceleration and deceleration, repeated ups and downs that violate the simpleton’s model. This is a clue that sea level rise is more complex than simple linear trend or constant acceleration. It’s that pesky “nuance” and “complexity” thing again. But if sea level doesn’t follow a strictly, perpetually accelerating path, Burton and others will suggest that the scientists who study the impact of man-made global warming have grossly misjudged the whole phenomenon. Such a suggestion is appallingly naive — it’s the simpleton’s viewpoint of Burton and others which is grossly misguided.

The scientific thing to do is to try to understand these changes using — oh, I don’t know, how about … physics. Let’s compare the simpleton’s viewpoint to that of Vermeer & Rahmstorf (2009). Burton takes a pot-shot at such efforts when he says:

Yet Shepard, et al, postulate 20 inches of sea level rise for a shorter 69 year period (and call it “modest and probable”), based on models which indicate that sea level rise should be accelerating in response to higher atmospheric CO2 levels. But the data indicate that those models are wrong, sea level rise is not accelerating.

I suspect this is his attempt to smear the results by association, since fake skeptics have made it a point to smear the results of computer models (i.e., computer simulations). Not only are they wrong about computer models, the “model” of Vermeer & Rahmstorf isn’t even a computer model. It’s a simple (but not simplistic) physical model based on the radical notion that sea level rise is influenced by temperature.

Vermeer & Rahmstorf fit a physical model of sea level rise to temperature change, finding that

When applied to observed data of sea level and temperature for 1880–2000, and taking into account known anthropogenic hydrologic contributions to sea level, the correlation is > 0.99, explaining 98% of the variance. For future global temperature scenarios of the Intergovernmental Panel on Climate Change’s Fourth Assessment Report, the relationship projects a sea-level rise ranging from 75 to 190 cm for the period 1990–2100.

Three things should be noted. First, the correlation of their model output with observations, in excess of 0.99, puts the lie to Burton’s claim — the foundation of his (and others) insistence on ignoring everything but the existing linear trend — that “the data indicate that those models are wrong.”

Second, the Vermeer & Rahmstorf physical model shows both acceleration and deceleration of the rate of sea level rise. Just as the observed data show.

The thin red line shows annual average observed sea level data, to which Vermeer & Rahmstorf have done what actual scientists who want to understand reality do — they’ve corrected for known sources of variation, tectonic and reservoir effects. The thicker red line shows the smoothed version of same. The dark blue line shows the result of their model, which reveals that both acceleration and deceleration are features of the 20th century in this physical model. Also shown is the estimate using only the first half of the data (green) or the second half of the data (light blue). Note that the model result (dark blue) almost obscures the observed sea level (red) because of the close match.

It should be taken as a lesson in understanding, that even a simple physical model can reproduce both the acceleration and deceleration observed in the sea level data. It’s really only the first steps toward nuance and complexity — their model doesn’t include a lot of things, such as the observable impact of el Nino on sea level fluctuations — but even the most rudimentary of physical models not only reproduces obvious features that linear or constant-acceleration models can’t, it also fits observations better.

Third, projecting their model into the future they estimate sea level rise 1990-2100 of between 0.75 and 1.9 meters. That’s quite a bit larger than the actually rather conservative value of 0.5 meters used by Shepard et al.

As for the third severe problem with the comments, it really is true that when it comes to time series, making a long-range forecast of a complex physical system by extrapolating a simple trend far into the future is a fool’s errand. Let me give you an example.

For several years now I’ve forecast the annual minimum in Arctic sea ice by computing the existing trend and extrapolating that trend into the future. One year into the future. But I’ve said repeatedly that such extrapolation can only be considered valid in the short term. Suppose we had projected Arctic sea ice decline by extrapolating an existing trend into the more distant future? Let’s take the annual minima of Arctic sea ice extent from 1979 through 1999, and use it to forecast 2000 through 2012. I’ll use the annual minimum of daily extent data from NSIDC. Here’s the data used to compute the trend, for which I’ll choose a quadratic regression to allow for acceleration:

Now let’s compute the extrapolation:

Notice that for the immediate future, up to about 2006, it’s not too bad. But for even a modestly greater time the projection falls flat on its face. The actual decline in Arctic sea ice was way faster than the existing trend suggested. If we look just at the errors from this simplistic model we see this:

By the time we get to this year — a mere 12 years into the future — the projection is off by 2 million square kilometers.

Yes, projections of future sea level rise really should be based on physical models, not on extrapolation of existing trends whether they include acceleration or not. Yet Burton, in his comment, closes by suggesting this:

However, all is not lost for this report. Long Island will probably experience 20 inches of sea level rise by about 2200. So if they just change “2080″ to “2200,” the report will be useful for projecting the impact of sea level rise on Long Island residents 190 years from now.

Not only does Burton utterly fail to realize the folly of projecting sea level rise for the 21st century based on extrapolating a simple trend, not only has he suggested that laws should be enacted preventing the state of North Carolina from officially doing otherwise, he actually suggests that this is a valid way to plan for the risk of sea level rise nearly two centuries into the future.

That’s worse than just a fool’s errand. It’s reckless.

As far as the Shepard et al. paper is concerned, the salient point of all this brouhaha is that If you disagree with the sea level forecasts, take it up with Rahmstorf and Vermeer and Grinsted and Nicholls and Cazenave. In my opinion, it is downright unethical and somewhat cowardly to use the simple application by Shepard et al. of very plausible results from others, as an excuse to attack those very plausible results from others. Why then did this happen?

I can only offer my opinion, which is this:

Burton and Boretti and Parker, and the journal’s editor Tad Murty, can’t reply directly to Vermeer and Rahmstorf and Grinsted and Nicholls and Cazenave in the peer-reviewed literature because they don’t have a leg to stand on. Based on the comment by Burton, and the similarly foolish ones by Boretti and by Parker, any such attempt would be laughed right out of the peer-review process. Instead, they used the paper by Shepard et al. as a convenient excuse to put their foolishness in the peer-reviewed literature in response to a paper which doesn’t even deal with the issue of forecasting sea level rise.

Just my opinion.

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55 responses to “Unnatural Hazards

  1. A tour-de-force putdown of Burton. I look forward to his attempt at defending himself.

    In more interesting scientific questions:
    1) Is there an explanation for the high rates of SLR pre-1900? The 10 mm residual from the Church & White, and the 40 from the New York Battery, seem surprisingly high to me.
    2) While I appreciate the Vermeer and Rahmstorf approach is an interesting attempt at a semi-emiprical solution to these questions, and better than a linear or quadratic model, I still have my doubts as to the robustness of the method – and the divergence of the light blue/green lines would seem to support some of my doubts.

    Thanks again for your in-depth analysis,


    [Response: I have my doubts too. But this much is clear: when planning for future risk, we cannot dismiss or ignore this (and other) forecasts which meet or exceed the figure adopted in Shepard et al. Such dismissal/ignorance is reckless.]

    • I’m not quite sure I am getting this. If you look at a data set that can be roughly approximated as linear trend + parabola (as in the case here) and remove the linear trend you are left with a residual that is roughly a parabola symmetric to the center of the data set. The beginning and the end of the residuals data set ought to be roughly equal. That’s pretty much what I see in the residuals of NYC and C&H.

      If you are looking for rates of change, you need to keep in mind that the slope on the left is negative and hence subtracted from the linear trend slope whereas on the right side they add to each other. Not having the lowess data at hand I did the next best thing(TM). I loaded Tamino’s graph into a graphics editor, fitted lines visually noting their slope and ran with that. From this endevour I get slopes of -4.0 mm/yr and +3.2mm/year for the initial and final “straight” sections of the NYC residuals. The underlying linear trend is +2.83mm/yr. Hence the actual trends at the beginning and the end are -1.2 mm/yr and +6.0 mm/yr (keep in mind, these results were derived using Eyeball Mark II).

      P.S.: Figures of the lowess fit slopes + trend slope may be nice to have.

      • Thanks for correcting my confusion bluegrue – I just made myself an artificial dataset, SLR starting at 0.1 units/timeperiod, with an increasing rate of 0.001, and an increasing rate of rate of 0.0001, for 40 time periods, and got a nice parabola out when taking the residual from the linear fit, starting at +0.3, dipping to -0.2, and rising to +0.4. Of course, averaging to zero.

        So, basically, when you look at a detrended residual, an upward parabola is indicative of an overall acceleration, and a downward parabola is deceleration.

        I still think I prefer Tamino’s linear trend for different time periods graphs as being more intuitively transformable to actual rates of rise for me. But both approaches pretty clearly demonstrate net acceleration over the time period of the dataset…

  2. The distractions coming from multiple people with no relevant qualifications sounds to me like a watered-down version of the “Serengeti strategy” described by Michael Mann.

  3. Please, please tell me that you are going to write this up as a note/comment and submit it to the journal.

  4. I wish Burton would just detrend himself.

  5. For those who do not know, the South Shore of Long Island is a long strip of low barrier islands. The most valuable land is closest to the shore and the lowest and most subject to flooding, including, of course, the Hamptons. As Eli often points out, a flood tide hitting that area would cause so much monetary damage that it would pay for just about any action the US takes to limit climate change.

    • Unless the action taken fails to prevent the flooding of the Hamptons. In that event, you have accrued both the cost of the failed mitigation and the cost of the flooding of the Hamptons.

  6. Does mean she’s already garnered three cites though. Does the old h-index no harm…

  7. David B. Benson

    two n’s

  8. The US Navy formally asked the National Academy to come up with sea level rise numbers they should pay attention to. The NAS responded with the National Security Implications of Climate Change for US Naval Forces which recommends that the Navy

    “should expect roughly 0.4 to 2 meters global average sea level rise by 2100, with a most likely value of 0.8 meter. Projections of local sea level rise could be much larger and should be taken into account…. US naval leadership… should be aware that this estimate is subject to change, and it should be reviewed routinely for any significant change.”

    The report found that

    “neither regional nor global sea level rise is of primary interest in determining naval coastal station vulnerability. Rather it is the increased vulnerability associated with extreme events (storm surges) and their dependence on changes in regional sea level, tidal amplitudes, and the nature of extraordinary meteorological forces that are of greatest importance”.

    Which about sums up what the NAS could be expected to say to the Navy at this time.

    A scientist suffering attacks such as Shepard might tell her attackers to take it up with the NAS and the US Navy. The Seals might be standing by….

    The Dutch plan for sea level rise uses 40 cm by 2050, between 65 and 100 cm by 2100, and up to 4 meters by 2200. Wired had some details in an article.

    Hansen said this in his recent TED talk: Most estimates are that, this century, we will get at least one meter. I think it will be more if we keep burning fossil fuels, perhaps even five meters, which is 18 feet, this century or shortly thereafter.

  9. Has the Boretti comment been published? Can’t find it. Parker and Burton are linked from the article

  10. “If you disagree with the sea level forecast, take it up with Rahmstorf and Vermeer and Grinsted and Nicholls and Cazenave.”

    but they are experienced scientists, much harder to scare than a young scientist publishing her first paper.
    Just sayin’

  11. What I am trying to figure out is how a peer reviewed journal gets such an extremist anti-science editor. Given that, I wonder what the editor had to say about the original manuscript. Is Murtry really the editor-in-chief? In some case, authors of original papers get to comment on comments and both the commenters and original authors get to be peer reviewers for each other’s comments. That would make for an interesting scenario. In any case, I don’t think that Shepard is likely to feel bad about the extra attention that her publication generated in the journal.

  12. That area is also a sea level rise hot spot according to the USGS.
    Between 1950–1979 and 1980–2009, SLR rate increases in this northeast hotspot were ~ 3–4 times higher than the global average.
    Full article here.

    [Response: I blogged about it here and here.]

  13. Tamino, what smoothing function did you use for the smoothed Battery data (battery_detrsmooth.jpg)?

    [Response: A lowess smooth.]

  14. So I downloaded the annual sea level data from the Battery here:


    I looked at the period from 1975-present (basically, the AGW era). There were a couple of years with missing data; I infilled those by averaging the preceding and following years.

    The linear trend over that period is +4.4mm/year. Simplistically projecting that trend forward to 2080, assuming no acceleration at all, would yield a sea level rise of +30cm from 2012 to 2080. Projecting a quadratic trend would yield +63cm by 2080. (The r2 for both models is around 0.67).

    Using various start years (1970, 1975, 1980) and linear and quadratic trends, I get projected SLR at the Battery ranging from a low of +25cm to a high of +97cm. Which is kind of nifty, because the estimate that Dr. Shepard used in her paper (+50cm by 2080) is almost exactly in the middle of this range.

    Obviously, this is absurdly simplistic — just looking at the recent trend and projecting it forward. But that’s what David Burton is recommending — ignore everything that physics tells us to expect, and just assume that past trends will continue.

    So the figure that Dr. Shepard used for probable sea level rise in 2080 is very well supported by the same data that David Burton used in his “comment”. David Burton owes Dr. Shepard an apology.

    • Whoops, sorry, I left out a step in this paragraph above:

      “Using various start years (1970, 1975, 1980) and linear and quadratic trends, I get projected SLR at the Battery ranging from a low of +25cm to a high of +97cm. Which is kind of nifty, because the estimate that Dr. Shepard used in her paper (+50cm by 2080) is almost exactly in the middle of this range.”

      The actual mean of +25cm and +97cm would be +61cm, which is higher than the estimate that Dr. Shepard used for sea level rise by 2080.

      But averaging all six of the projections (three start years [1970, 1975, 1980] times two trend types [linear, quadratic]) gives a mean projection of +50.2cm by 2080. That is only 0.2cm higher than the value that Dr. Shepard used.

      So, bottom line, her assumption of 50cm by 2080 is very, very well supported by the actual data. As I said, David Burton owes Dr. Shepard — and all of us — an apology.

      • Does anyone expect Burton to actually apologize? I suspect the best Shepard will get is to have the comment deleted. In a world with perfect integrity, Burton would also re-examine his expertise in preparing material that could significantly affect residents of North Carolina.

        I wonder if Burton is going to go all Curtin and produce a work of art in the medium of rationalizing.

  15. Horatio Algeranon

    The most misguided aspect of what Burton and the others are saying (eg, with the “2200″ and “190 years” comment) is that it gives the impression that there is nothing to worry about (at least not for a century or more) and no real need to prepare for future storms, which could not be further from the truth.

    Regardless of whether sea level rise is 7 inches or 20 by 2080, the threat from storm surges (measured in feet (not inches)) to low-lying coastal areas is very real. And the fact that the (rather limited number of) storm surge risk maps eg, like this one have increments of “3 feet” should be a clue.

    As Christine Shepard pointed out in an interview for Grist

    Part of the point of this study was to create maps that communities can use to develop targeted approaches to hazard mitigation. We created a social vulnerability index to help map these communities so that hazard mitigation policies or grants could be targeted towards communities that are socially vulnerable, to reduce their risk. And for critical facilities and infrastructure, just to have easily accessible maps of where these are with respect to present and future storm surge risk is very valuable for community planning.

    So, what Burton and the others are effectively saying to at risk coastal communities (some of which may not currently have any maps and plans in place) is “Don’t worry about developing up-to-date storm surge maps, evacuation plans and infrastructure because sea level is going to rise only 7 inches”.

    Or, in short: “Don’t worry, be happy”

  16. as you stated :
    Third, when it comes to time series, anyone who knows the difference between a sphincter and a hole in the ground also knows that for complex physical processes, making a long-range forecast by extrapolating a simple trend far into the future is a fool’s errand.
    please define how long the long range is then, because we should believe the forecast that in 2100 or so, the artic would be ice-free. in my opinion , 90-odd years is long

    [Response: Is this a lame attempt at humor? Or are you just being obtuse?]

  17. Actually, I do not find it all that surprising that the Editor is in the anti-science camp. I have found several scientists that I respect quite a bit who count themselves “skeptics”. In discussing their objections with them, I have always found them to be ill informed regarding the science. They have merely found something that “didn’t add up” in their mind and so dismissed the entire field. In many cases, in discussing things further, the real reason has come to light: they don’t know what to do about the problem, and so the problem must not exist.

    This is of course a classical logical fallacy–argument from consequences. It is also proof of the vulnerability of scientist to the same foibles that plague our entire species if we relax our watchfulness and refuse to do the math.

  18. You can hardly call Burton’s interest “economic development.” It’s more like short term profit for real estate developers, that is of no sustained benefit for the owner (whose house washes away) or community (which foots the bill for infrastructure and insurance).

    • The locals and state officials in a state like North Carolina aren’t completely mad. You might ask: how can it possibly benefit anyone to develop new infrastructure right where it will be wiped out as accelerating sea level rise increases the chances of the extreme event likely to cause that? Here is an answer:

      States have a lot of say in what appears on a National Flood Insurance Rate Map. N.C. was even supposed to be a model to other states. It was designated by FEMA to be the first state to assume primary responsibility for coming up with the map. See this press release.

      If you control what goes on the map, you can transform useless subject to frequent extreme event flooding lands no one could develop because no one will insure into valuable insurable real estate with a stroke of your pen. Federally regulated banks can then legally lend developers what they need to develop infrastructure on it. And buyers of that infrastructure will be able to buy flood insurance at affordable rates.

      Everyone benefits until the sh*t hits the fan. But then, because of federal disaster legislation, very many people benefit again.

      The President declares disaster areas under the terms of the Stafford Act. Suddenly, federal funds backed ultimately by the US general taxpayer flow into areas some local state has allowed to be developed in harm’s way and a general absolution is performed. Risk is not reevaluated. The goal of the Act is to enable restoration of what was there.

      So there is a benefit to North Carolina and most of its citizens to do their best to circumvent rationality and continue to develop lands subject to being wiped out too soon for any of it to make economic sense, because they benefit from the economic activity when the development first takes place, and they benefit when the federal funds flow in to redevelop the area after it gets wiped out. And all along, people get to enjoy living near the sea.

      The debate about how wise this all is from the national perspective has been going on for a long time. I looked into a bit of it when I found myself astonished to hear about N.C. apparently attempting to legislate against sea level rise. The 1994 Galloway Study was a landmark. The Guardian dug up Galloway in 2012 and asked him for comment:

      “We have been very good at letting people continue to live in harm’s way,” said George Galloway, who was commander of the Army Corps at Vicksburg in the 1970s. “But how much longer can we continue to do that since we know with climate change we are going to have more floods than in the past?”

      FEMA Director Fugate gave a speech recently: ” “We cannot afford to continue to respond to disasters and deal with the consequences under the current model. Risk that is not mitigated, that is not considered in return on investment calculations, will often set up false economies. We will reach a point where we can no longer subsidize this.”

      • A simpler explanation:

        The retirement horizon.

        If it happens 2-3+ decades from now, the decision makers will be comfortably past the point of being held responsible.

      • After the almost complete lack of accountability (for anyone but whistleblowers) in recent years, does any US official really worry about being held accountable for anything they decide or do?

        If so, someone should tell them not to worry.

      • It took awhile to hold Augusto Pinochet accountable as well.

      • Can happen anywhere. I lived in Brisbane, Australia 2002-2011. Early in my stay there, a flood level map was leaked, showing a lot of areas popular with developers would be inundated in a major flood. The city council insisted it was a draft and not correct, and later produced a much more optimistic map. In January 2011, Brisbane had a major flood, and guess which map was right?

  19. Horatio Algeranon

    Shepard et al responded to Burton, basically saying (in a very nice way) that he is ignoring physics and chemistry.

    • IMHO, they got the right answer, like the one Tamino provided : if you’re not happy with the projections chosen, go complain with people actually computing it, we are focusing on possible impacts. Their area of expertise does not cover physics of SLR, and thus they use a wide range of projections provided by other scientists.

      And I just love the first sentence :] Shepard may become one day an excellent troll, to the level of Lewandowsky :]

  20. Susan Anderson

    Those graphs are rather ominous. Great article.

  21. The link to Shepard’s paper is not working

    [Response: It's working for me.]

  22. “We have been very good at letting people continue to live in harm’s way,” said George Galloway..

    To avoid confusion: Need to correct one of the Guardian’s typos.This did not refer to the MP for Bradford West. It should have been Gerald not George. .

  23. Re: Link to Sheppard.
    Useful reply, thanks. Linux: the link still doesn’t work in Konqueror but is OK in Firefox

  24. Why was I not surprised to read that another Canadian denier, Madhav Khandekar, is on the journal’s editorial board. Khandekar is affiliated with Heartland and the Canadian ant-science, oil funded lobby group “Friends” of Science.

    One has to wonder– were these ludicrous responses solicited by Murty? What is the nature of the relationship between Murty and Burton?

  25. The discussions here about both the projection we used and the editorial policies at Natural Hazards are worth having and likely wouldn’t have taken place without this blog post. We received the Parker comment which references the Boretti comment before the Boretti comment was even published (it still is not online). We prepared a joint response to both Boretti and Parker: http://springerlink3.metapress.com/content/k6v032h48q248285/

    A quick google search of both Boretti and Parker shows them to be active in submitting comments like these to papers that do not make a SLR projection but rather apply projections as ‘what if’ scenarios. Boretti and Parker have also submitted several short communications in Coastal Engineering and Natural Hazards. In one of Parker’s ‘communications’ in Natural Hazards he cites the wattsupwiththat blog. A colleague joked to me “my son’s high school won’t even let him do that!”

    Tad Murty emailed me to tell me that our paper is the only Nat Haz paper ever to have received three comments and he congratulated me on this. He also said comments will be ‘entertained’ until December 31st, 2012 so I encourage those with interest to submit a comment. It would be interesting to see how high the bar is for comments in support of our applied projection.

    Thank you,

  26. And after all that work by Tamino, Burton has failed to show up to defend his argument or to even comment. Quelle surprise.

  27. Timely post on sea level change by Rob Painting at Skeptical Science with more to come:
    Sea Level Isn’t Level: Ocean Siphoning, Levered Continents and the Holocene Sea Level Highstand

    [Response: You have to put the "/" before the "i" in a tag to turn off italics.]

  28. I know that, Tamino, I just didn’t take enough care when typing that comment. Thanks for fixing it.

  29. As I mentioned, I like the “linear trend for different time spans” graphs as being intuitively clear in their depiction of how the recent trends are definitely larger than the trend over longer time periods… I’d be interested in a companion graph which might show a sliding window of 30 year trends from different start dates which would elucidate how much trends vary over time…

  30. Hmm. I found raw data at http://www.psmsl.org/data/obtaining/stations/12.php. Ironically, linked to by Steve Goddard. Whose webpage stated, “Tide gauges show that sea level in Manhattan is rising about 4mm per year and accelerating.” So even Goddard recognizes that there is acceleration!!! (of course, he then puts up a picture of suspiciously un-provenanced satellite data to claim that the satellites show no such sea level rise near New York, but, you know, 1 out of 2 is infinitely better than his usual batting average).

    Anyway, I did a 30 year analysis (using annual averages, filling in blank years with the average of the surrounding years), and found that the rate of SLR over the past 30 years (eg, 1980-2010, more than 4 mm/year) was similar to the rate from the 1920s to the 1950s (also more than 4 mm/year). Of course, that makes some sense when matched with the Rahmstorf semi-empirical work, as the rate of temperature rise in the 1920-1950 time-period was a local maximum, if not quite as fast as the rise in the past several decades…

  31. So — no journal focusing on unnatural/anthropogenic hazards?

  32. Here’s one for that: http://www.newscientist.com/article/mg21528842.100-cause-test-could-end-up-in-court.html

    “… A new statistical test could cut through all that (see “Causality test could help preserve the natural world“). George Sugihara says his CCM test can identify connections that would otherwise remain obscure.
    CCM is at an early stage, and already has its detractors. It clearly needs to be tested further before we can tell how robust its predictions are. But some people may not wait for such validation.
    What if, for example, a causal link could be shown between some set of greenhouse gas emissions and a particular manifestation of climate change? ….”

  33. Boretti and Parker are one and the same – I phoned the University of Ballarat today and they confirmed that Alberto Boretti has changed his name to Albert Parker.

    It seems that there is a bit of disentangling of papers to be done, especially if “we received the Parker comment which references the Boretti comment before the Boretti comment was even published ….. ” (Chris Shepard’s post).

  34. I can only find 2 comments at the springer link. Boretti’s isn’t there.


    So, is Boretti’s comment located somewhere else or has it been removed?

  35. I gather Chris Shepard has seen it (since she had to respond to it) – so it seems to have got stuck somewhere in the system.