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A sea level Golden Horseshoe nominee*

Filed under: — gavin @ 14 October 2012

I was reading a sign high on the wall behind the bar:

‘Only genuine pre-war British and American whiskeys served here’

I was trying to count how many lies could be found in those nine words, and had reached four, with promise of more …”

Dashiell Hammett, “The Golden Horseshoe”

Google News occasionally throws up some obscure postings that I would never otherwise come across. A recent example was a letter to an editor of a Scottish newspaper (not my usual reading material) declaring that “Climate change is not man-made”. The letter itself is uninteresting – a basic confusion between weather and climate seguing into a NIMBY-ish rant about windmills. Ho hum.

However, in one of the comments from a “Dr John Cameron, St Andrews” (posted 9/Oct/2012), there was this unrelated pseudo-factoid:

As regards the catastrophic sea level rise in the Pacific, it became obvious some 20 years ago that results from island tide gauges did not support computer predictions. Scientists from Flinders University in Adelaide set up new, modern, tide-gauges in 12 Pacific islands to test whether there was in fact any evidence of sinking. Recently the whole project was abandoned as there had been no sign whatsoever of a change in sea level at any of the 12 islands for the past 16 years.

Now this is specific enough to probably actually refer to something real, but doesn’t pass the sniff test for something that might actually be true. Scientists don’t set up monitoring stations only to get the answer they want and then stop monitoring if it doesn’t happen. This only happens in the fevered imaginations of conspiracy theorists. So I was intrigued enough to investigate what this actually referred to…

The easiest way to look for this is to search for the exact string – specifically the second sentence. Google comes up with 1000 or so very close antecedents – particularly with the “new, modern, tide-gauges in 12 Pacific islands” section. The links are to comment threads on partisan websites, the standard climate ‘skeptic’ blogs, and even a mention on SkepticalScience. The comments stretch back around 5 years. Some of the examples give an actual source for the remarks (unlike Dr. Cameron’s version) – one Dr. Vincent Gray – a well known pseudo-skeptic. Some even cite the newspaper article they appeared in – a error-ridden puff piece by Lawrence Solomon at the Canadian Financial Post. Curiously, that online version of the article doesn’t have a publishing date – though secondary sources suggest it was published on Oct 26th 2007. The lack of a date means that people quoting it often claim that this is a ‘recent’ claim.

Going back a little further, Gray made similar claims in a July 2007 article:

A claim that Pacific Islands were sinking led to an investigation by Flinders University, Adelaide, which replaced all the tide gauges in 12 Pacific islands to attempt to find out whether it was true. The attempt has now been abandoned as a failure, as none of the 12 islands showed any significant change since 1991. The team tried to save face by claiming that all showed an upwards “trend” because the 1998 hurricane caused a temporary depression in the ocean. Since 1998 all have remained flat, and the main island of contention, Tuvalu, actually rose last year.

This is referenced to an actual report from the Australian Bureau of Meteorology about the “South Pacific Sea Level and Climate Monitoring Project” (SPSLCMP), dated November 2006. Now we are getting somewhere!

There are some obvious signs of confusion in the Gray/Cameron statements. Firstly, the Australian National Tidal Facility (which installed and monitored the tide gauges starting in 1991) used to be managed by Flinders University in Adelaide – but the facility was transferred to the National Tidal Centre run by the Bureau of Meteorology … in 2003!

Second, the SPSLCMP has been rolled out in stages starting in 1991: the third stage terminating in Dec 2005 – and they are now in stage IV. This might be the source of Gray’s claim that the project had been abandoned, though even the report he cited clearly states that the phase IV was started in January 2006 and was slated to continue at least another 5 years (at that time). The ‘last 16 years’ is a clue that the Cameron statement was obviously written in 2007 not 2012.

Finally, annual reports from SPSLCMP are available through to June 2011 – indicating a project that is very much ongoing and one that was not ‘abandoned’ before 2007.

So none of the statements that Gray (and Cameron) made about the project itself were true (either in 2007 or in 2012). But what about the sea level trends?

This is even odder. The report Gray cites states clearly that relative sea level trends (1992/3/4 to 2006) at all stations were positive (2.7 to 8.1 mm/year for the 11 of the 12 stations with long enough records). The 12th station at FSM was only installed in 2001 and the trends were very noisy (though positive). The Jun 2006 SPSLCMP report goes further and applies corrections for platform movement and the inverted barometer effect, concluding that trends ranged from 1.7 to 7 mm/year at the 11 longer stations. Note that these trends may include a component of subsidence/uplift of the islands themselves and so are the numbers most relevant for local planning (not eustatic sea level change). But so much for not finding a trend!

As one would expect, monitoring has continued since 2007, and in the latest report (June 2011), the 11-station trends range from 2.8 to 7.7 mm/year (and +17.0 mm/year at the FSM station). The monthly data series are available here for people to check for themselves. Comparisons with the satellite altimeter records show a reasonable coherence since the West Pacific sea level has risen faster than the global mean (at least partially related to the number of recent La Niña events).


Trends using all data up to June 2011.


Roughly comparable trends (1991-2012) using the satellite altimeter record.

In summary, every piece of concrete information in the Gray/Cameron statement is wrong. They were wrong even in 2007 when the statement was written and even wronger when it was cut-and-pasted without sources in 2012. Yet demonstrating this took a a few hours of googling, a little familiarity with the issues and people, and obviously is not going to be done by every reader. Thus a statement which clearly make no sense goes unchallenged for years and keeps getting regurgitated. Sure, no single statement like this is likely going to change anyone’s mind about anything, but this one and others like it form part of a drumbeat of disinformation, which by repetition, becomes embedded and hard to shift.

A good question would be why I bothered to research a claim in an obscure comment, on an obscure letter to the editor in a regional newspaper I have never read, and I don’t really have a good answer. Clearly, looking for substantive points in newspaper comment threads is a bit of a fool’s errand, but I was still surprised at how completely wrong every single aspect of the comment was. Given that I did look into it, it is worth sharing here – just on the off chance it will save someone else the bother.

* The Golden Horseshoe award, whose name derives from the Hammett quote above, is for spectacular wrongness in the climate discussion, first initiated by SomeAreBoojums, and occasionally revived by the Wabett.


251 Responses to “A sea level Golden Horseshoe nominee*

  1. 101
    Patrick says:

    Dave Person @61: Thank you. I copy your perspective. I used to think that
    indignation about real climate science was just Galileo and Darwin all over
    again. I don’t think that now: I think it’s Galileo and Darwin continued.
    Don’t burn yourselves out.

    People didn’t like it when their planet was cast out of the center of the universe, even though it was a step to greater learning. Now they don’t like it when they find that the planet is feeding back effects of their presence, in numbers over seven billion, and of their choices, decisions, minds, and best-laid schemes.

  2. 102
    Craig Nazor says:

    Dan H – You did not answer all my questions. I asked 4 questions, and you gave me 2 “nos.” Was it your intention to be confusing? I asked:

    1) Do you believe that the sea level rise observed in the past 100 years is accelerating?

    2) Do you believe that the observed sea level rise is the result of AGCC?

    3) Do you think that this acceleration of sea level rise should cause any concern for human civilization?

    4) Do you see how what you are doing is exactly what this particular post is pointing out?

    If we assume that your “nos” answer questions one and two, then please produce ANY peer-reviewed science that states that sea level rise is not accelerating. And if you believe that AGCC is not causing the observed sea level rise, then please produce ANY peer-reviewed science that contains an alternate explanation as to why sea levels are rising. And if your answer to that is “we don’t know,” then please produce evidence of ANY kind of scientific consensus that shows that the majority of climate scientists agrees with that assessment. It would be helpful if you could do this all without having your post lost down the borehole again.

    If you cannot do that, then please SERIOUSLY consider an answer to my last question.

  3. 103
    tamino says:

    Re: #102 (Craig Nazor)

    please produce ANY peer-reviewed science that states that sea level rise is not accelerating

    There are publications making this claim, but they’re unreliable. There is for instance Houston & Dean, and there has recently been a concerted effort to dispute sea level acceleration in the journal Natural Hazards such as this and this. Fascinating story.

  4. 104
    Dan H. says:

    Craig,
    I actually answers all your question, but will repeat them with clarity. Answers to your questions in order:
    1. No. Sea level rise has shown two periods of acceleration during the 20th century, as mentioned previously. SLR did accelerate (past tense) during the 1990s, but data for the most recent decade is no different from the 20th century trend. There has been much debate as to the reasons and significance of this change. See tamino’s post for additional references.
    2. The observed SLR is a direct result of the warming temperatures that have occurred since the late 19th century, both natural and anthropogenic.
    3. Not at the present rate.
    4. I will combine this answer with a response to Jim’s post. The SLR during the 20th century was higher than the average over the past two millenia – this is a direct reponse to Martin’s (not Marco’s) earlier comment about extrapolating back to the Roman Era. As Jim pointed out, which if you read my earlier posts is similar to my contention, if you average SLR over the past 8000 years, it is similar to that observed suring the 20th century. However, most of that rise occurred over the first 500-1000 years, with much smaller intervening rise. This is the point that I have been trying to make for the past few days, but people seem to have trouble distinguishing the forest from the trees. Cannot you not see how others have confused an average rate with a continuous rate? All the references I provided previously show this. Somehow, people here are trying to misinterpret these references, in a manner similar to the gist of this thread, which I have continued to acclaim.

  5. 105
    chris says:

    O.K. that’s pretty straightforward Dan H.

    We can summarize:

    - The glacal/interglacial (Holocene) transition was associated with a warming that drove a massive sea level rise. Since the ice sheets take a very long time to come to equiibrium with a new temperature, the ice sheets continued to melt well after the warming transition ended, so that melting and sea level rise continued to 6-7000 years ago. (the papers you linked to show this).

    - Sea levels have changed rather little, if anything falling a tad, since the Roman period 2000 years ago to the start of the anthropogenic era. (Lambeck’s work especially).

    - The small falling sea level trend up to the start of the anthropogenic era reversed in the middle to late 19th century to become a slow increasing trend at the start of the 20th century, accelerating through the 20th century. From 1870-1920 sea levels were rising around 1 mm/yr; throughout the middle to late 20th at around 2 mm/yr. Sea levels are rising a tad upwards of 3 mm yr-1 now. (see e.g. link in Charles’s post #84.)

    - This observed acceleration of sea level rise as global temperatures increase in very much what one expects from a combination of thermal expansion and ice sheet melt, with the rate of both increasing as the global temperature increases. You said as much with your perceptive “SLR mimics temperature rise” assertion.

    - Since “SLR mimics temperature rise”, we expect that SLR will continue to accelerate throughout the coming decades as the radiative imbalance at the top of the atmosphere continues to drive temperatures upwards.

    - The sea level rise under the influence of enhanced temperatures resulting from anthropogenic enhancement of the greenhouse effect will continue for a very long time indeed, unless the temperature rise is reversed.

    None of that is very controversial I think.

  6. 106
    Jim Larsen says:

    104 Dan H said, “Cannot you not see how others have confused an average rate with a continuous rate? ”

    Lawyering is interesting but not useful. “Over the five minutes my client interacted with the so-called victim he inflicted an average of a small woman’s touch’s worth of force.” Yep, an apt description of shooting someone in the head, but we’d expect the jury to “not get” the argument “right”.

  7. 107
    Hank Roberts says:

    >>> ANY peer-reviewed science that states
    >>> that sea level rise is not accelerating
    >>
    >> There are publications making this claim,
    >> but they’re unreliable.
    – Tamino

    > the most recent decade is no different from
    > the 20th century trend…. See tamino’s post
    – Dan H.

    Dan H. throws another ringer.

  8. 108
    Dan H. says:

    Chris,
    Excellent summary, although I made no forward going statment. I am not sure that I could decipher your quoted trend from the referenced link, but it does show 225mm of rise over 140 years, with a few hesitations in the 1880s, 1920s, and 1960s. The highlighted trend is slightly lower than that observed in the 1940s.

    Jim,
    Excellent analogy, and I think it hammers home my point quite effectively.

  9. 109
    Mike Roddy says:

    One could search US media and be more likely to find an error filled climate story than an accurate one. The reason is not reporting incompetence, but self censorship and messaging from the owners. Much media income is derived from cars and various profligate consumer items. Journalists are the last ones to rock the boat.

    There is no widely read and comprehensive climate change media criticism in this country. Reporters (as opposed to beancounters) would actually like to see this happen, and their bad stories checked.

    About 87% of Europeans believe that climate change is a serious problem, a stat that is not even comprehensible in our country.

    Their media is less entwined with fossil fuel advertisers, and there is still a public service tradition. Here in the US, that is considered quaint. We must revive it.

  10. 110
    Eric Rowland says:

    Regarding the idea of consistent SLR over the last several thousand years being “not even wrong”, I’d suggest this idea has been easily falsified in this thread which would make it just plain vanilla wrong. There is nothing unusual about the wrongness of the idea. Maybe it’s a nitpick but using “not even wrong” as a streetcorner perjorative for ideas that are just dumb makes no sense to me.

  11. 111
    Craig Nazor says:

    Dan – So you agree with Chris’ post? That is very surprising, judging from what I can get from you answer @104. If you agree with Chris, then why would you answer “no” to question 3?

    Your answer to question 4 is about as clear as mud. This whole post is discussing how some people take the scientific facts and try to twist them around (sometimes far past any truth and into the realm of fantasy) to support their own contentions. Combining your answers @104, your answer of “no” to question 3, and your agreement with Chris’ analysis, I think you have binders of facts without any bit of rational analysis.

  12. 112
    Rob Painting says:

    Dan H – “As Jim pointed out, which if you read my earlier posts is similar to my contention, if you average SLR over the past 8000 years, it is similar to that observed suring the 20th century

    Wrong – note the three metre beaches which are endemic to the equatorial oceans. Rates of sea level rise as small as 0.5mm per year during the last 4 thousand years would have completely submerged these exposed coral, wave marker notches, and sediments. Their dating, and their existence proves you are wrong.

    And your previous reference to the Fleming (1998) paper was a predictable move. I already anticipated the obvious contrarian tactic of referencing outdated research – that’s one reason why it was included in my post on Holocene sea level highstands.

    Have you watched this Jerry Mitrovica video yet? The evidence expounded by one of the world’s foremost experts on this topic is aimed squarely at the myths you are attempting to propagate here. Little wonder you don’t want to watch it. Never mind, it is useful to bring to the readers attention again and again.

  13. 113
    Hank Roberts says:

    It’s always about rate of change.

  14. 114
    Rob Painting says:

    Chris @ 105 – One further thing. As the analysis by Tamino makes clear, there have been short-term periods throughout the 20th Century where sea level rise has decelerated, but the long-term trend has been one of global sea level acceleration.

    If we look just at the trend over the satellite altimetry period (1993 to 2011) it appears to have decelerated yet again. Part of this trend over the satellite-based observational period is due to the preponderance of La Nina in the latter part of the record, because La Nina is an interval when greater-than-normal rainfall is concentrated over land – and that rainfall is ultimately derived from the global oceans, which causes global sea level to temporarily fall. This sea level “pothole” trend has completely reversed this year as ENSO neutral conditions have taken hold.

    The other contributor to the temporary deceleration is probably due to the slowdown in ocean heat content accumulation between 2004-2008. I say temporary because the Earth’s energy imbalance is close to 0.6 W/m2 over the last decade or so, and the Earth must warm to come back into balance. This warming will melt more land-based ice, and induce further thermal expansion of seawater over the coming decades. So the long-term expectation is that sea level will continue to rise, and will accelerate if the vast ice sheets of Greenland and Antarctica begin to disintegrate.

    Now you probably know all this, but the casual reader may not.

  15. 115
    Hank Roberts says:

    and life is full of little surprises:

    http://www.nature.com/nature/journal/v487/n7408/abs/nature11292.html

    Nature | Letter 日本語要約
    Inland thinning of West Antarctic Ice Sheet steered along subglacial rifts
    Nature 487, 468–471
    (26 July 2012)
    doi:10.1038/nature11292

    “… Here we report the discovery of a subglacial basin under Ferrigno Ice Stream up to 1.5 kilometres deep that connects the ice-sheet interior to the Bellingshausen Sea margin, and whose existence profoundly affects ice loss…..
    … the ‘Belgica’ trough, which today routes warm open-ocean water back to the ice front7 to reinforce dynamic thinning….”

  16. 116
    Craig Nazor says:

    Dan H – I sincerely hope that you looked at the Jerry Mitrovica video that Rob posted, as he blows your answer to my question number 1 completely out of the water, along with a couple of your other arguments, to boot. I would be interested in hearing how you believe that he gets it wrong, and you get it right.

    Your answer to my question number 2 is also evasive. What percentage of observed recent sea level rise do you believe has been caused by AGCC, as opposed to “natural” causes? What would those other causes be, what might be driving them, and where is your scientific evidence to support your claims?

    In the four years I have been discussing this topic with you, it appears that your opinion has not changed in the least about any of this. Am I wrong? Does your opinion ever change? What causes it to change, if or when it does?

  17. 117
    Jim Larsen says:

    108 Dan H said, “Jim, Excellent analogy, and I think it hammers home my point quite effectively.”

    Wow…

    109 Mike R said, “Their media is less entwined with fossil fuel advertisers, and there is still a public service tradition. Here in the US, that is considered quaint. We must revive it.”

    That depends on whether you like stakeholder capitalism, as practiced by the USA in the 1950s, or shareholder capitalism, as practiced today.

    112 Rob P said, “Wrong – note the three metre beaches”

    I just took a random internet google. Are you saying the chart I happened to find is wrong?

    116 Craig N asks, ” What causes it to change, if or when it does?”

    Death. Duh.

  18. 118
    John Peate says:

    It is a pity that you did not do this several months ago. At that time, I was engaged in countering the “good Doctor’s statement on a denilaist blog. I did not have a good explanation. Good enough, though.

  19. 119
    Shane P says:

    At 117+ comments this may just fall off the end BUT, this kind of thing is all too common in regional newspapers and in English language newspapers in non English speaking countries.

    My old “local” paper The Border Watch frequently carries letters and opinion pieces that are “skeptic” in view. This may not be surprising as this is the “home town” of famous climate researcher and skeptic Leon Ashby.

    Except for the Murdoch owned exceptions in Australia the skeptics don’t neccesarily dominate the news in the major papers. But in the smaller regional local papers hungry for content the situation is different.

    The same may be true in non English speaking countries with an English language paper.

    For Example The Jakarata Post is always running demonstrably false skeptic letters by Viv Forbes senior memeber of the Australian Climate Science Coalition … and I bet you can guess from that title what they do.

    The sheer number of rubbish letters published from Queensland in a newspaper in a country in which Mr Forbes can have no actual interest is suspicious. Does he get paid for every published piece?

    The army of darkness is focussing their attention on the lesser but still widely read “local” papers. Their message is especially well received where the local population is employed in traditionally “anti greeny” occupations like forestry, mining and farming/fishing. At this grassroots level is the climate message being heard?

    Given that anti greens sentiment also appears correlated with anti intellectual sentiment, any “city expert” who appears to state the actual facts can be expected to meet a less than friendly reception.

    Denialists play up to the country vs city (or intellectual vs “I ain’t got no uni education but…”) identity politics of this. A speaker at these meetings needs not only to “win” the factual debate but the emotional debate as well.

    For all his flaws Steve Irwin was the kind of person for this audience.

  20. 120
    Mike Roddy says:

    Very interesting, if unsurprising. “Skeptics” have been given the green light by the US media to go ahead and lie like hell. Nobody is calling them on it in a systematic way, since it is a big task, requiring a lot of man hours (as you discovered in debunking a single comment).

    We need infrastructure to do this properly, something I and some colleagues are working on. Interested parties can email me at
    mike.greenframe@gmail.com

  21. 121
    prokaryotes says:

    Mike, please you and others can use this place http://climatestate.com/forum/other-projects.html to announce your project. With a weblink on other websites (backlink) your project also gains in google rankings and you help to improve the content and inspire others.

  22. 122
    Hank Roberts says:

    > Belgica trough
    Is there more than one of these?

    Here’s a “Belgica trough” (2005 article) under the Greenland ice:
    http://ars.els-cdn.com/content/image/1-s2.0-S0304420305000058-gr1.jpg
    http://www.sciencedirect.com/science/article/pii/S0304420305000058

    but recent articles refer to a “Belgica trough” channeling warm meltwater under the Antarctic ice:
    http://scholar.google.com/scholar?as_ylo=2012&q=“belgica+trough”

  23. 123
    Hank Roberts says:

    oboy. Amazing what nobody knew existed til this year:

    http://www.ouramazingplanet.com/3238-rift-discovered-antarctica.html

    “… The Ferrigno Rift’s “existence profoundly affects ice loss,” Bingham and co-authors from the British Antarctic Survey wrote in a paper published in Nature … (July 25).

    … the study authors write, the rift is providing a channel for warm ocean water to creep toward the interior of the West Antarctic Ice Sheet, gnawing away at the Ferrigno Glacier from below.

    …. the overall effects could have implications for the stability of the West Antarctic Ice Sheet, which is responsible for 10 percent of global sea level rise that is currently happening.

    Scientists are still only just beginning to understand the myriad mechanisms that control the seemingly dramatic melting observed in regions of West Antarctica, and how climate change is affecting all the moving parts….”

  24. 124
    Hank Roberts says:

    I wonder if Woodfortrees could be persuaded to add ocean time/trend data sets. Foreseesforseas?

  25. 125
    Alexandre says:

    Re Adam Sacks

    I agree that it’s way past the time for scientific reticence.

    I have met laymen who were interested enough to actually read parts of the AR4 and said “if AGA is so certain, why don’t they plainly say so?”

    The broader public will not figure out the physics for themselves and then demand an according policy from their government. It’s unrealistic to count on that level of public knowledge to enable change.

    The message to the public should be as short and straight as that we have about tobacco in some countries. I picture credible institutions like NOAA or NASA or USGS endorsing billboards saying something like

    “We thought Arctic sea ice would be as low as this only in fifty years. It’s happening now.”

    “Remember last summer’s heatwave? That will be our mild summer in 2060. Protect our children’s future. Stop global warming.”

    “40% of our freshwater comes from that glacier. Protect our water. Stop warming.”

    At this point, no caveats, no graphs, no uncertainty ranges. If 9 out 10 planes crash over a certain route, we don’t say “It’s very likely that an unwanted outcome would take place. On the other hand, the survival rate suggests further research could yield different practices to be adopted”. The proper answer would be more like “no way”.

    The present issue is no longer a scientific issue. It’s a PR one. PR has its own rules and laws, and they must be observed if you want to successfully get your message across.

  26. 126
    Dan H. says:

    Craig,
    I was unable to access the posted site for the video referenced, but was able to access it from Youtube (assuming it is the same Jerry Mitrovica video). I fail to see how this video “blows my answer completely out of the water.” His graphs shows SLR since 1930 from tidal gauges to average 2.3mm/yr, yet the most recent 10-yr trend is also 2.3mm/yr.

    You also asked if my opinion ever changes, and what may cause it to change. Simple, a change in the scientific data. In the four years that we have been debating climate change, the GISS 120-month trend in global temperatures moved from +0.022C/decade to -0.093C/decade (lest you think I cherry-picked those value, the last 180 months shows a similar change in rate). During that time, the 120-month trend in SLR dipped from 2.88 mm/yr to 2.28 mm/yr. Since you are always asking for possible alternative explanations, Rob gives a few of the possible explanations for the recent observances in post #114.

    Contrarily, the Arctic sea ice has shown a greater rate of decline during the past four years, resulting in my opinion changing to an ice-free summer Arctic in 2028. Jim can attest to this. Last I knew, I was still alive.

    So, I will ask you the similar question, what will cause your opinion to change?

  27. 127

    Thanks, Dan H, for confirming that you cherry pick the data to frame your opinions.

  28. 128
    Dan H. says:

    Jeffrey,
    I could always reverse my opinion on the Arctic sea ice, if you think that it is cherry-picked. Do you have anything to show that the sea ice is not melting at a faster rate?

  29. 129
    Hank Roberts says:

    http://sealevel.colorado.edu/

    Nerem, R. S., D. Chambers, C. Choe, and G. T. Mitchum. “Estimating Mean Sea Level Change from the TOPEX and Jason Altimeter Missions.” Marine Geodesy 33, no. 1 supp 1 (2010): 435.

    DOI 10.1080/01490419.2010.491031

  30. 130
    Hank Roberts says:

    http://sealevel.colorado.edu/content/2011-la-ni%C3%B1a-so-strong-oceans-fell
    Abstract
    Global mean sea level (GMSL) dropped by 5 mm between the beginning of 2010 and mid 2011. This drop occurred despite the background rate of rise, 3 mm per year, which dominates most of the 18-year record observed by satellite altimeters. Using a combination of satellite and in situ data, we show that the decline in ocean mass, which explains the sea level drop, coincides with an equivalent increase in terrestrial water storage, primarily over Australia, northern South America, and Southeast Asia. This temporary shift of water from the ocean to land is closely related to the transition from El Niño conditions in 2009/10 to a strong 2010/11 La Niña, which affected precipitation patterns world-wide.
    DOI 10.1029/2012GL053055
    Geophys. Res. Lett.

  31. 131
    Hank Roberts says:

    “The computed rate of global mean sea level rise from the reconstructed time series is 1.97 mm/yr from 1950 to 2009 and 3.22 mm/yr from 1993 to 2009.”
    http://sealevel.colorado.edu/content/reconstructing-sea-level-using-cyclostationary-empirical-orthogonal-functions

    DOI 10.1029/2011JC007529

  32. 132
    Craig Nazor says:

    Dan H, when asked, “Do you believe that the sea level rise observed in the past 100 years is accelerating?” answers: “No. Sea level rise has shown two periods of acceleration during the 20th century, as mentioned previously. SLR did accelerate (past tense) during the 1990s, but data for the most recent decade is no different from the 20th century trend.”

    To that same question, Jerry Metrovica of Harvard says; “2mm of sea level rise per year, which is roughly the rate during the 20th Century, was anomalous, and is something the Earth has not seen for about 10,000 years – when it was in the midst of the last ice age deglaciation. [...] The rate of sea level rise has increased from the 20th century average of 2-2.5mm per year to over 3mm per year during the record of satellite-based observations (1993-present). [...] The future sea level rise projections of the 2007 IPCC report were too low. Current sea level rates are already at the uppermost range of projections, which reinforces this view. ”

    The video to which I (and others) linked gives very strong evidence as to why this is true;

    http://www.skepticalscience.com/Jerry-Mitrovica-Current-Sea-Level-Rise-is-Anomalous-Weve-Seen-Nothing-like-it-for-the-last-10000-Years.html

    Dan – for a reasonable discussion, please watch the video and respond to Metrovica’s evidence.

    I also asked you this question, to which you have not yet responded: “What percentage of observed recent sea level rise do you believe has been caused by AGCC, as opposed to “natural” causes? What would those other causes be, what might be driving them, and where is your scientific evidence to support your claims?”

    What causes my opinion to change is by considering scientific evidence produced by knowledgeable people, and then having discussions and asking questions of such people. I must admit that I also learn a lot by researching and responding to claims I believe to be false (such as some of your claims). This web site is just such an invaluable resource that allows me to do all these things.

  33. 133
    Dan H. says:

    Craig,
    I am not even going to attempt to estimate what percentages are contributing to SLR. There are simply too many factors involved; glacial runoff, glacial isostatic rebound, thermal expansion of the oceans, groundwater pumping, not to mention the negative affect of dams. All this is without calculating what percentage of warming due to AGCC, other manmade influences, or natural causes. Maybe someone else here can help you with this one.

    By the way, I did watch the video. That was where I got some of the data for my previous post. Did you even read my previous post?

  34. 134
    Craig Nazor says:

    Dan H – you said: “His [Jerry Metrovica’s} graphs shows SLR since 1930 from tidal gauges to average 2.3mm/yr, yet the most recent 10-yr trend is also 2.3mm/yr.” Metrovica says: “The rate of sea level rise has increased from the 20th century average of 2-2.5mm per year to over 3mm per year during the record of satellite-based observations (1993-present).” You and Metrovica completely disagree, but Metrovica fills the video with interesting and compelling evidence to support his opinions. You also said: “That [Metrovica's video] was where I got some of the data for my previous post.” Where did you get the rest of it? You are obviously cherry picking again, Dan. So tell me, why should we believe the disappearing logic of the mysterious Dan H over Jerry Metrovica of Harvard, particularly when you won’t even clearly identify your arguments or sources of information, and won’t even acknowledge the arguments of your opponent? You are not partaking in an honest scientific discussion – your are engaging in some kind of weird debate where you are trying to trick someone into agreeing with you based on your own private logic, supported by untraceable “facts,” pretending that you actually AGREE with your opponents.
    And then when I ask you what else might be contributing to the observed sea level rise, you say, essential, I don’t know, there are way too many possibilities – go ask someone else to defend my indefensible statements! You act like I am asking you because I somehow TRUST your information and would accept it at face value. What I am actually trying to do is MAKE YOU DEFEND your illogical arguments, if you can. Really, Dan, is that the BEST you can do?

  35. 135
    Dan H. says:

    Craig,
    You are not paying attention close enough. Metrovica and I do not “completely disagree,” in fact, we actually agree. His figure of 3 mm/yr is over the timeframe 1993-2011. I am not disputing this. I used a figure from 2002-2012, and acknowledge that the rate was higher from 1993-2002 (in fact, the SLR was ~4mm/yr then).

    [Response: Why? What happened in 2002 that makes it a particularly important point to break a calculation? Surely it couldn’t be because that has a smaller trend? Hmm… – gavin]

    The data comes from the University of Colorado, which uses the satellite altimetry (see the link in post #129), this data is not “untraceable,” but readily available to anyone.
    Your last post is rather humorous in that you criticize my use of scientific data from research journals in favor of a Youtube video. Then, make some inane arguments about logic, just because I do not have all the answers to your questions. If you are really interested in all the particulars about contributions to sea level rise, I suggest you do some research of your own.

    Here are a few starting points:

    http://www.agu.org/pubs/crossref/2012/2012GL051230.shtml

    http://www.agu.org/pubs/crossref/2012/2012GL053055.shtml

    http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11621.html

    http://www.agu.org/pubs/crossref/2012/2012GL052885.shtml

    http://www.nature.com/nature/journal/v482/n7386/full/nature10847.html

  36. 136
    Dan H. says:

    Gavin,
    Nothing special, just the most recent decade.

  37. 137
    Hank Roberts says:

    Killfile would be a welcome addition here.

  38. 138
    Hank Roberts says:

    Dan H. missed this one, for his catalog of little differences that don’t make much difference compared to the rate of change:
    http://www.sciencedirect.com/science/article/pii/S0273117712003778

    Method: pick threads out of the pattern and suggest, imply, or hint that if they were different they’d change the picture.

  39. 139
    GDWilliams says:

    What may have given your intuition a hint that something was amiss here was perhaps the way the author kept referring to the goal of the research as being an effort to validate whether or not the islands were sinking, when in fact it was to see if sea levels are rising. This may seem like mere semantics, but the difference is one of accuracy over illusion. A difference that good science (and scientists) strives to maintain.

  40. 140

    From the essential pages of AGW Observer.

    Kelley et al 2012, “Maximum late Holocene extent of the western Greenland Ice Sheet during the late 20th century.”

    …We find that many land-terminating sectors of the ice sheet, in addition to our study area, may have attained their maximum late Holocene extent during the 20th century. This suggests a lagged ice-margin response to prior cooling, such as the Little Ice Age, which would imply significant retreat of land-terminating sections of the Greenland Ice Sheet in response to 20th and 21st century warming may be yet to come.

    I really don’t know how much SLR there will be this century, but the evidence is clear enough that the seas will rise – based on likely increases in temperature and paleo-climate data. If I was thinking of buying a coastal property and wanted it to go to heirs; I wouldn’t go any lower than 10m ASL. That’s giving a large safety factor to allow for increased erosion and brine percolation into ground water. IMO the time has definitely come for people to accept that they buy coastal properties at their own risk. That just leaves us to worry about what international aid we give to the destitute in countries like Bangladesh.

    We will face enough problems this century without bailing out idiots who ignore the science.

  41. 141
    Unsettled Scientist says:

    > Nothing special, just the most recent decade. The data comes from the University of Colorado.

    It is important to note the reason for the lower number in the most recent decade is because of the unusually strong 2011 La Nina. That fact (and link) was already provided by Hank in post 130, but since someone has missed it and instead tried to use the average to imply a slowing of sea level rise it is worth repeating.

    http://sealevel.colorado.edu/content/2011-la-niña-so-strong-oceans-fell

    “Global mean sea level (GMSL) dropped by 5 mm between the beginning of 2010 and mid 2011. This drop occurred despite the background rate of rise, 3 mm per year, which dominates most of the 18-year record observed by satellite altimeters. Using a combination of satellite and in situ data, we show that the decline in ocean mass, which explains the sea level drop, coincides with an equivalent increase in terrestrial water storage, primarily over Australia, northern South America, and Southeast Asia. This temporary shift of water from the ocean to land is closely related to the transition from El Niño conditions in 2009/10 to a strong 2010/11 La Niña, which affected precipitation patterns world-wide.”

    DOI: http://dx.doi.org/10.1029/2012GL053055

    The clear point here is that the average for the most recent decade is not because of some change in the underlying processes contributing to sea level rise, but is simply a reflection that for a year excessive rains dumped the ocean water on land. All the melting and heating is still increasing the sea level. It is actually more concerning that we can lose mass in the ocean due to inland sequestration and still have an average sea level rise.

    In fact, if that poster implying a slowing of the sea level rise had read the links he shared he would know this. It is in fact the title of his second link in post 135. You’ll note that link clearly states the rate of SLR is *not* 2mm/year. There is in fact no sign of slowing. Using “the most recent” decade smoke & mirror is the same as using ENSO anomalies to pretend that global warming isn’t real.

  42. 142
    Hank Roberts says:

    I mention a cite with a link;
    Dan claims it supports his claim.

    Look for yourself. If nothing else, look at the picture:
    http://sealevel.colorado.edu/files/2012_rel4/sl_ns_global.png
    and the sidebar: The 2011 La Niña: So strong, the oceans fell

  43. 143
    John E. Pearson says:

    Somehow I can’t help but see Gavin as the boxer.

    http://www.youtube.com/watch?v=6QqEoz_3vEM

  44. 144
    Craig Nazor says:

    Dan H – I did not post, or in any way refer to, a Youtube video.

    Metrovica says in the video: “2mm of sea level rise per year, which is roughly the rate during the 20th Century, was anomalous, and is something the Earth has not seen for about 10,000 years – when it was in the midst of the last ice age deglaciation. […] The current rate of sea level rise varies from place to place, however this is to be expected due to the location and presence of land-based ice sheets, and gravitational changes brought about by the disintegration of these present-day glaciers and ice sheets. […] The rate of sea level rise has increased from the 20th century average of 2-2.5mm per year to over 3mm per year during the record of satellite-based observations (1993-present). […] The future sea level rise projections of the 2007 IPCC report were too low. Current sea level rates are already at the uppermost range of projections, which reinforces this view.”

    Do you agree with all of that? If not, with what do you disagree? Those statements are in the video to which you claim to “actually agree.”

    What I pointed out is that you haven’t posted the science to back up your own statements about the cause of the observed SLR. I do not believe that the observed SLR over time has any other major component than AGCC.

    Your first link is a very small amount of water, which is BY DEFINITION an anthropogenic effect. Your second link is to a temporary and transient phenomena, and cannot support a continued rise over time. The third link says that Antarctica is melting and is contributing to SLR. Are you claiming that this melt is not an anthropogenic effect? The POSSIBLE 60-year oscillation of SLR mentioned in the fourth link is not global in effect, and the full amount cannot yet be measured. The fifth study refers to glacial and icecap melt. I would consider this to be an anthropogenic effect, also. If you disagree, what else would you claim is causing it? None of these studies support your claim that a significant proportion of the observed SLR is non-anthropogenic.

  45. 145
    Dan H. says:

    Craig,
    I do not know where you got your assumptions. When did I ever make the claim that you state in your last sentence?

    Everything I stated, I backed up scientifically. There are many more papers on the various contributions to SLR, if you care to search them. Several posters have added to the possible cause(s) of the slowing in observed SLR recently. Do you disagree with them and the scientific links they posted also? Are you truly interested in the SLR contributions? You seem to be extremely critical of the views of others. What is your view on the contributions to SLR, and can you cite evidence to support it?

    As I mentioned earlier, I was unable to open the link provided to the Mitrovica video, but was able to view it on Youtube. It does not appear to be available in scientific venues.

    Here is a graph similar to that which Mitrovica presented:

    http://www.skepticalscience.com/images/sea_level_reservoir.gif

  46. 146
    Hank Roberts says:

    C’mon, guys, he’s playing Audie Murphy tying up an entire battalion of the enemy army single-handedly by spoofing.

    He’s slippery, he will keep you going in circles for days chasing phantoms if you try to get hold of anything he posts.

    Look back at the original post. He’s not the topic here.

  47. 147
    Hank Roberts says:

    PS, spelling helps: scholar.google.com/scholar?q=Mitrovica+sea+level

  48. 148
    Dan H. says:

    OK Hank,
    I will stop replying to his questions, if you insist.

  49. 149
    Hank Roberts says:

    Get a blog, Dan.

  50. 150
    SecularAnimist says:

    Hank Roberts wrote: “Get a blog, Dan”

    You mean this isn’t Dan H’s blog?

    Because, you know, looking over this thread, he seems to own it.


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