Measured sea level rise drops 30% with “pause” greater than half of RSS measurement period.
Guest essay by Larry Hamlin
A paper titled “The rate of sea-level rise” published in Nature Climate Change on March 23 by Cazenave, et al. shows that during the last decade the rate of sea level rise has declined by about 30% during the period 2003 through 2011 to about 2.4 mm/year from the rate of 3.4 mm/year in the period 1992 through 2002. The paper argues that this decrease is the result of short-term natural climate variability which it attempts to remove to reveal the “true” global warming signal with the end result being to “adjust” the lower measured sea level rate upward.
Dr. Judith Curry addresses this new paper in her April 24th post “Slowing sea level rise” where she argues that there is no convincing way to adjust out the effects of El Nino/LaNina events from the measured sea level rise record and that natural variability has dominated sea level rise during the 20th century.
The crux of her arguments are presented below with the figure shown from the UN IPCC AR5 WGI report showing that sea level rise has varied significantly since 1900 in a manner which Dr. Curry concludes demonstrates dominance by natural climate variation forces.
The slowing in the measured rate of sea level rise during the last decade has occurred while the RSS satellite measured global lower-troposphere temperature record now has more than half of its 35+ year temperature record, which began data collection in January 1979, showing no global warming whatsoever since August 1996 as demonstrated in the graph below taken from an article in Real Science addressing this “pause”.
Dr. Curry draws the following conclusions based upon these measured and perhaps interrelated outcomes by noting:
“Once again, the emerging best explanations for the ‘pause’ in global surface temperatures and the slow down in sea level rise bring into question the explanations for the rise in both in the last quarter of the 20th century. And makes the 21st century of sea level rise projections seem like unjustified arm waving.”
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@Kev-in-Uk says: April 28, 2014 at 12:27 pm
+100
SLR of 2 or 3 mm per year is so far below the noise level as to be in-credulously irrelevant.
First JJ refers to Trenberth, Hansen, and Co. opinion that ENSO should be a ‘global warming’ signal. That is because they are ignorant of the origin and history of ENSO. ENSO is a resonant oscillation of ocean water from side to side in the Equatorial Pacific, powered by trade winds, and has a period of five years. This resonant period can be temporarily changed by other oceanic happenings but it will always return when the disturbance is over. One such disturbance was the super El Nino of 1998 that carried far more warm water across the ocean than any regular ENSO oscillation is capable of. If you look at any of the long-term temperature curves you can trace that five year resonance back to the early nineteenth century. I just counted the frequency of occurrence of El Nino peaks recorded by HadCRUT3 and found that for approximately sixty percent of the cases peak-to-peak distance between El Ninos was close to five years. This has been going on as long as the present equatorial current system in the Pacific has existed, which is to say since the Panamanian Seaway closed. As to sea level, what is missing in all this talk is correction for water held in storage by reservoirs. This was done only by Chao, Wu and Li [Science 320:212-214 (2008)]. They corrected all available sea level data for the effect of 29,484 reservoirs built since 1900. They found that the GSL curve, so corrected, became linear for the last 80 years with a slope of 2.46 millimeters per year. Anything that has been linear that long is not likely to change anytime soon. This gives us a centennial rise of 24.6 cm, or just under ten inches. It is lower than any predictions from IPCC I have seen and is likely to be closest to real sea rise when the results come in.
Dave Wendt says:
April 28, 2014 at 12:59 pm
I tend to avoid commenting on most of these sea level posts because unlike most of the world I find the satellite sea level data to be a complete crock.
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LOL…you’re not alone Dave
Here you go….. http://www.aviso.oceanobs.com/fileadmin/documents/calval/validation_report/EN/annual_report_en_2009.pdf
philjourdan says:
April 28, 2014 at 12:24 pm
@Latitude – Normal seems to be what ever they decide. Not something that is common in the history of the planet.
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pretty much…..who decided where that little zero line goes anyway
http://www.foresight.org/nanodot/wp-content/uploads/2009/12/histo3.png
ZombieSymmetry says:
April 28, 2014 at 12:47 pm
…
Eyeballing the graphs on Wikipedia, it seems to me that the noise in the data for the past 8000 year or so is around +/- 1 meter, conservatively: http://commons.wikimedia.org/wiki/File:Holocene_Sea_Level.png
…
It is far worse than that. There is very respectable evidence of mid-Holocene high stands that are between one and two meters ABOVE the present stand. Evidence of this comes from both northern and southern hemispheres. High stand strand lines have been mapped in Texas, Brazil, Australia, and various Pacific islands. There numerous methodological problems with trying to track sea level shanges, but there is wide support for the mid-Holocene highstand.
A good overview is Woodroffe and Horton 2005:
One point that the mid-Holocene marine highstand suggests is that the “Holocene” peaked at that time, and since then, we have been sliding slowly and unsteadily into the next glacial.
Lookie here smuck.
If you have bought, built, a luxury apartment – or any other kind of dwelling – near to the shores of San Francisco Bay – you may be having Al Gore as your neighbour – (rumours have it that Al has acquired a property, at a cost of $$$£££££££$$$$ gazillions – or maybe just a few millions) so, be afraid, be very afraid, cause our Al has only spent his “own money” in the public’s interest. – – – –
Al and his (Cocktails at dawn) friends are only there to monitor, at close quarters, the rapid sea level rises. Your property, however, will definitely be waterlogged by Christmas. And you, will have lost your money. SSSSSSSSSSSSSSSSSShi
The link disappeared there for Woodroffe and Horton. Here it is:
http://repository.upenn.edu/cgi/viewcontent.cgi?article=1022&context=ees_papers
Someone gets data from Wikipedia?
Thanks Dr. Brown.
> The paper argues that this decrease is the result of short-term natural climate variability
I’m really getting tired of this old phrase. I wish that warmists who can’t find the correlation they want with CO2 would go out and study what makes up “natural climate variability” instead of whining (or whinging) about it. They might learn something useful about the many sources of natural climate variability….
And if anyone sees Trenberth, suggest he dig under Hawaii to look for his missing heat. It might keep him busy for a while.
The absurdity of the “team” to actually believe that we can actually measure SL/R to the 1000th of an inch/meter is overwhelming. They would have us believe that the earth is a static perfectly proportioned ball and it’s just so darn easy when in fact it is anything but. As RGB notes the lack recent datum from GRACE (with all its warts) is telling. And this video from minute physics puts in all in perspective as the geodesists can only model SL to within ONE meter.
What the paper says: ” that during the last decade the rate of sea level rise has declined by about 30% during the period 2003 through 2011 to about 2.4 mm/year from the rate of 3.4 mm/year in the period 1992 through 2002″ contradicts the graph from Colorado which shows about a linear trend of 3.2 mm/year, no deceleration:
http://sealevel.colorado.edu/content/global-mean-sea-level-time-series-seasonal-signals-removed
However Colorado’s own data contradicts their graph if one looks at the historical values.
The overall increase was between 3.0 – rose to 3.5 in 2007 and then down to 3.2 in 2009.
The 3.5 mm/year in 2007 was the average computed/adjusted for the entire satellite data until then:
http://wattsupwiththat.com/2009/04/06/sea-level-graphs-from-uc-and-some-perspectives/
When I look now at the new data and it is again 3.2 mm/year for total:
http://sealevel.colorado.edu/content/global-mean-sea-level-time-series-seasonal-signals-removed
however including the additional GIA adjustment of 0.3 mm/year added in retrospect for the whole period ( I think this was done in 2011 or 2012 if I remember correctly – too lazy to check now…).
http://stevengoddard.wordpress.com/2014/03/24/the-global-isostatic-adjustment-scam/
So with the additional adjustment of more then 6 mm added in the last couple of years it cannot show the linear trend over all the data?
With the additional 0.3 the trend before 2007 should now show 3.8 mm/year and after 2007 should show less, something like 1.5 or 2 mm/year?
Gonzo says:
April 28, 2014 at 3:04 pm
The absurdity of the “team” to actually believe that we can actually measure SL/R to the 1000th of an inch/meter is overwhelming.
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but they can measure temperature, CO2 (13CO2), etc…..the same way
/snark
Looks like an analysis of El NINO.
Noise In, Noise Out.
In response to:
“shows that during the last decade the rate of sea level rise has declined by about 30% during the period 2003 through 2011 to about 2.4 mm/year from the rate of 3.4 mm/year in the period 1992 through 2002.”
What has not been made public is the recent satellite data shows the ocean level is now dropping slightly. The increase shown based on satellite data is due to adjustments. There is a climategate type problem and there is a genuine significant scientific mystery.
If we were not in the middle of the climate wars, the sea level rise ( higher than can be explained by thermal expansion or melting glaciers or ice sheets) and then fall would be acknowledged to be an unresolved paradox.
As the warmists do not understand the missing mechanism (that can caused the mid ocean level to rise or fall) and we are in the middle of the climate wars, they have hidden the dropping of the mid ocean surface by adjustments to the depth of the ocean which enables them to state the ocean level is increasing when the net ocean level is in the last 6 or so years is dropping slightly.
Early indication that there is a missing mechanism that is causing anomalously more mid ocean rise in level, is the fact that the tide gauge measure is less than ocean level measured by satellite. The satellite measurement is too high and cannot be explained by thermal expansion of the ocean.
ftp://falcon.grdl.noaa.gov/pub/bob/2004nature.pdf
Mass and volume contributions to twentieth-century global sea level rise
The rate of twentieth-century global sea level rise and its causes are the subjects of intense controversy1–7. Most direct estimates from tide gauges give 1.5–2.0 mm/yr, whereas indirect estimates based on the two processes responsible for global sea level rise, namely mass and volume change, fall far below this range. Estimates of the volume increase due to ocean warming give a rate of about 0.5mmyr21 (ref. 8) and the rate due to mass increase, primarily from the melting of continental ice, is thought to be even smaller. Therefore, either the tide gauge estimates are too high, as has been suggested recently6, or one (or both) of the mass and volume estimates is too low.
Looks like data for about 1.5 to 2 main cycles or so folks with some shorter periodicities overlaid plus some noise. Definitiely not linear, quadratic or even just monotone increasing.
Come back in 2050 or 2100 and we should have a robust data set and some preliminary analysis. In 2500 we should have enough data for a robust preliminary report and in 3000 we will have it nailed. No further comment at this time thanks.
Can someone PLEASE stop the children waving their arms?
Link to Dr. Curry’s article.
http://judithcurry.com/2014/04/24/slowing-sea-level-rise/
And this video from minute physics puts in all in perspective as the geodesists can only model SL to within ONE meter.
I’m glad you posted that, as my attempt to post it myself (in the middle of a much longer reply) got eaten by demons from hell — again — and I didn’t have the energy to repost. It is actually a fabulous video, and it explains a lot of the difficulty with trying to build the satellite measurements.
The good thing is that the satellite measurements and tide gauge data are basically independent and from now on will act as mutual sanity checks. As is the case with RSS/UAH LTT and the various GASTA measurements, it is simply no longer acceptable for any sort of growing divergence to exist between the two. So regardless of any growing pains or initialization or algorithm problems in the satellite measurements, they will fairly rapidly either agree in general with the tide gauge measurements or nobody will believe them, including the scientists responsible for them. So they’ll fix them.
As far as measuring mm-scale stuff regarding the sea level “anomaly” given the difficulty of establishing SL itself within less than about a meter, with tide gauge data it is probably in principle possible as long as one doesn’t overextend one’s prediction from what it is — “relative” SL measured at a variety of coastal sites, over time, averaged in a not-completely-insane way into an estimate of the non-isostatic component of SLR change. However, ultimately, one faces exactly the same difficulties when trying to compute GASTA (the surface temperature anomaly) to supposed 0.15C precision when the same models one uses to do so cannot estimate GAST — the actual average surface temperature — closer than about a degree C, and where e.g. HADCRUT5 and GISS LOTI often differ by several times 0.15C. SLR hadn’t reached that point as of 2007, but I suspect that by 2014 it has some pretty serious disparities (hence the lack of actual figures released to the public).
rgb
“””””…..NZ Willy says:
April 28, 2014 at 1:20 pm
The trend lines in the RSS temperature graph have no merit whatsoever because their ends do not connect. Displaying such lines is a stain on this website, viewed with disdain by any practicing scientist including me. ……”””””
Well if it was up to me, I would draw the first trend line from 1978 to 1994, which would be dead flat like the second line; and that would demonstrate that a step change occurred around 1996-7.
To draw a single straight “trend line” for that complete graph would be totally insane.
But then this practising scientist would never draw a trend line any how.
Why make up fiction, when you have the facts ??
And trend lines are pure fiction.
If you are unhappy with two trend lines; then make it three trend lines, and join them all; that would put my third trend line from 1994 to 1997.
From rgb
“””””…..As I said in an earlier reply, that’s why the oceans are an exquisite thermometer for the Earth……”””””
Professor; one can even make the argument that the oceans (sl) are an exquisite measure of total ocean heat.
If one assumes that the temperature coefficient of (linear expansion), is constant over the temperature range (from surface to bottom), and also the specific heat, then the sea level rise due to added heat in the sea, is essentially independent of how the heat distributes versus depth.
You can heat a lot of water a little, or heat a little a lot, and the total length change is the same, under the conditions I gave.
It appears to me that the overall trend in sea-level rise (SLR) is derived by averaging many, perhaps thousands, of data points over many years. This masks the areas of the ocean where sea level is falling. That alone should raise serious concerns.
Yet there is a bigger issue. I recently found that rainfall over the ocean correlates very well with SLR. Also a lack of rainfall correlates to sea level falling.
For the two graphics that show this, see
http://sowellslawblog.blogspot.com/2014/04/sea-level-rise-and-annual-rainfall.html
The question becomes, then, what effect does rainfall over the oceans have on the SLR? Is the dramatic increasing SLR graph at all valid?
rgbatduke: “Assume that this length is (say) 1 km, or 10^6 mm. Even temperature changes that are one part in 10^5 absolute could then produce changes of several mm over 1 km.”
Thanks a bunch. That’s something that had never occurred to me.
Since you’ve obviously thought about this, though, perhaps you could also let us know how big you think the confounding factors you know of are. If we assume (contrary to fact) a uniform coefficient of expansion, then a 2-mm/yr trend over a century means 0.2 m out of 4267 m average depth, and that ratio, divided by 2.14 x 10^(-4) %/K, yields only 0.22 Celsius degrees of ocean-temperature change over the past century if I haven’t made another calculator error.
Now, you scientist types use words like “thermocline” that, in addition to frightening us natives, makes us wonder whether things aren’t more complicated. If we’re talking about using the ocean to bound radiative forcing plus feedback, as they’re talking about today over at Dr. Curry’s, I’d be willing to accept that it doesn’t much matter; if the ocean heats less somewhere, it heats more somewhere else. But as to the effect on temperature up here where we live, well, that’s something else; there must be some kind of multiplier that results.
And what about the non-uniform coefficient of expansion? Perhaps it’s not too non-uniform at the depths where most of the temperature change occurs. Or maybe it is.
:Finally, when you say, “People make noises of a shift in the ratio of land freshwater and sea water, but I don’t think there is any compelling evidence for it,” I take it you’re not convinced by what Leonard Weinstein is (or may be) saying http://judithcurry.com/2014/04/28/an-alternative-metric-to-assess-global-warming/#comment-535465 at Dr. Curry’s?
In any event, might you conclude that as far as what Pielke, Sr., McNider, and Christy are proposing today at Dr. Curry’s the Argo system isn’t all that necessary if we have good sea-level information?
Corrigendum in my comment:
“2.14 x 10^(-4) %/K” includes the percent sign erroneously .
As mentioned in one of the blogs above the “powers” started adjusting the reported sea level rise by considering the subsidence at the bottom of the sea. This correction is misleading since it adds the subsidence (which reduces actual sea level) to the measured sea level ignoring the fact that subsidence creates more volume to store more water. I believe this mis- represents the impact/risk of sea level rise.
My question is: do the plots above incorporate the soil subsidence thus exaggerating the risk.