New study using GRACE data shows global sea levels rising less than 7 inches per century

Finds sea levels have risen over the past 9 years [2002-2011] at a rate of only 1.7 mm/yr, equivalent to 6.7 inches per century, matching tide gauge data rates.

baur_fig_lossgain

The paper corroborates the NOAA 2012 Sea Level Budget which finds sea levels have risen at only 1.1-1.3 mm/yr over the past 7 years from 2005-2012 [less than 5 inches/century], and the paper of Chambers et al finding “sea level has been rising on average by 1.7 mm/year over the last 110 years.” 

From the IPCC FAR Chapter 5.5.2: Holgate and Woodworth (2004) estimated a rate of 1.7 ± 0.4 mm yr–1 sea level change averaged along the global coastline during the period 1948 to 2002, based on data from 177 stations divided into 13 regions. Church et al. (2004) (discussed further below) determined a global rise of 1.8 ± 0.3 mm yr–1 during 1950 to 2000, and Church and White (2006) determined a change of 1.7 ± 0.3 mm yr–1 for the 20th century.

The paper:

Impact of Continental Mass Change on Rate-of-Rise of Sea Level

Present-day continental mass variation as observed by space gravimetry reveals secular mass decline and accumulation. Whereas the former contributes to sea-level rise, the latter results in sea-level fall. As such, consideration of mass accumulation (rather than focussing solely on mass loss) is important for reliable overall estimates of sea-level change. Using data from the Gravity Recovery And Climate Experiment satellite mission, we quantify mass-change trends in 19 continental areas that exhibit a dominant signal. The integrated mass change within these regions is representative of the variation over the whole land areas. During the integer 9-year period of May 2002 to April 2011, GIA-adjusted mass gain and mass loss in these areas contributed, on average, to -(0.7 ± 0.4) mm/year of sea-level fall and + (1.8 ± 0.2) mm/year of sea-level rise; the net effect was + (1.1 ± 0.6) mm/year. Ice melting over Greenland, Iceland, Svalbard, the Canadian Arctic archipelago, Antarctica, Alaska and Patagonia was responsible for + (1.4±0.2) mm/year of the total balance. Hence, land-water mass accumulation compensated about 20 % of the impact of ice-melt water influx to the oceans. In order to assess the impact of geocentre motion, we converted geocentre coordinates derived from satellite laser ranging (SLR) to degree-one geopotential coefficients. We found geocentre motion to introduce small biases to mass-change and sea-level change estimates; its overall effect is + (0.1 ± 0.1) mm/year. This value, however, should be taken with care owing to questionable reliability of secular trends in SLR-derived geocentre coordinates.

A slide show on the paper is available here: Baur_GGHS2012

Reference

Baur, O., Kuhn, M. and Featherstone, W.E. 2013. Continental mass change from GRACE over 2002-2011 and its impact on sea level. Journal of Geodesy 87: 117-125.

Background

The authors write that “present-day continental mass variation as observed by space gravimetry reveals secular mass decline and accumulation,” and that “whereas the former contributes to sea-level rise, the latter results in sea-level fall.” Therefore, they state that “consideration of mass accumulation (rather than focusing solely on mass loss) is important for reliable overall estimates of sea-level change.”

What was done

Employing data derived from the Gravity Recovery And Climate Experiment – the GRACE satellite mission – Baur et al. assessed continental mass variations on a global scale, including both land-ice and land-water contributions, for 19 continental areas that exhibited significant signals. This they did for a nine-year period (2002-2011), which included “an additional 1-3 years of time-variable gravity fields over previous studies.” And to compensate for the impact of glacial isostatic adjustment (GIA), they applied the GIA model of Paulson et al. (2007).

What was learned

Over the nine years of their study, the three researchers report that the mean GIA-adjusted mass gain and mass loss in the 19 areas of their primary focus amounted to -(0.7 ± 0.4 mm/year) of sea-level fall and +(1.8 ± 0.6) mm/year of sea-level rise, for a net effect of +(1.1 ± 0.6) mm/year. Then, to obtain a figure for total sea-level change, they added the steric component of +(0.5 ± 0.5) mm/year, which was derived by Leuliette and Willis (2011), to their net result to obtain a final (geocenter neglected) result of +(1.6 ± 0.8) mm/year and final (geocenter corrected) result of +(1.7 ± 0.8) mm/year.

What it means

The final geocenter-corrected result of Baur et al. is most heartening, as Chambers et al. (2012) indicate that “sea level has been rising on average by 1.7 mm/year over the last 110 years,” as is also suggested by the analyses of Church and White (2006) and Holgate (2007). Concomitantly, the air’s CO2 concentration has risen by close to a third. And, still, it has not impacted the rate-of-rise of global sea level!

References

Chambers, D.P, Merrifield, M.A. and Nerem, R.S. 2012. Is there a 60-year oscillation in global mean sea level? Geophysical Research Letters 39: 10.1029/2012GL052885.

Church, J.A. and White, N.J. 2006. A 20th century acceleration in global sea-level rise. Geophysical Research Letters 33: 10.1029/2005GL024826.

Holgate, S.J. 2007. On the decadal rates of sea level change during the twentieth century. Geophysical Research Letters 34: 10.1029/2006GL028492.

Paulson, A., Zhong, S. and Wahr, J. 2007. Inference of mantle viscosity from GRACE and relative sea level data. Geophysical Journal International 171: 497-508.

This essay was derived from several sources: CO2Science.org, The Hockey Schtick, and independent located content.

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Latimer Alder

Oh dear. Living only 50 feet above the tidal River Thames, was I premature to commission a landing stage and boathouse at the end of my garden?
Perhaps I’d better delay the opening gala and regatta until next year…… Mrs Alder has bought a new hat and frock too……

MangoChutney

@Latimer
I’m sure you can make use of the hat and frock at the weekends 😉

ThinkingScientist

ITs strange how study after study, based on better and better methds, still seem to come up with a steady rate of sea level rise less than about 2 mm /yr. Even the IPCC reports give these figures.
And yet, year after year, the popular meme of accelerating sea level rises keeps doing the rounds. In 2001 the UK Chief Scientist announced the 6 m in 100 years claim. More than ten years on, has sea level risen the predicted 600 mm (2 ft)? Nope, just 17 mm or so.
Sea level is rising

ThinkingScientist

…very, very slowly!

pat

u mean this isn’t true?
2 July: Radio Free Asia: Parameswaran Ponnudurai: Climate Change Conjures Up ‘Alarming’ Scenarios in Southeast Asia
Imagine these scenarios: The rice bowl of Vietnam cracking. Popular diving spots in the Philippines, Malaysia, and Indonesia lying idle with no tourists. Nearly half of Bangkok inundated with water.
Well, they could become a reality in 20 to 30 years—no thanks to the adverse effects of climate change in Southeast Asia…
The warming climate will push up the sea level in the region and cause an increase in heat extremes, a higher intensity of tropical cyclones, and ocean acidification stemming from excess carbon dioxide in the air, according to the latest edition of the (World) bank’s “Turn Down the Heat” report…
The Mekong Delta is also Vietnam’s most important fishing region. It is home to almost half of Vietnam’s marine fishing vessels and produces two thirds of Vietnam’s fish from aquaculture…
By 2050, the sea-level rise is expected to increase by over 30 percent of the total current area—1.3 million hectares— affected by saltwater intrusion in the delta, the report said…
It also warns that floods due to sea-level rise will engulf 43 percent of Thailand’s capital Bangkok around 2025, and about 70 percent in 2100.
Bangkok together with Jakarta, Yangon, Manila, and Ho Chi Minh City are projected to be among cities in Southeast Asia to be most affected by sea-level rise and increased storm surges…
http://www.rfa.org/english/commentaries/east-asia-beat/climate-change-07022013165938.html
Radio Free Asia
Radio Free Asia (RFA) is a private, nonprofit corporation that broadcasts and publishes online news, information, and commentary to listeners in East Asia who do not have unfettered access to free, reliable domestic news media. RFA is funded in part by an annual grant from the Broadcasting Board of Governors (BBG)…
RFA “aims to fill a critical gap in the lives of people across Asia.” The entity was originally established by the United States Congress through legislation enacted in 1994. Its mandate is to broadcast timely, accurate news happening within its broadcast region that is “otherwise not reported”…
CRITICISM
According to a report by the Congressional Research Service of the U.S. government, official state-controlled newspapers in China have run editorials claiming Radio Free Asia is a CIA broadcast operation.
North Korea’s state-run Korean Central News Agency has referred to Radio Free Asia as “reptile broadcasting services…
http://en.wikipedia.org/wiki/Radio_Free_Asia

Latimer Alder

@MangoChutney

I’m sure you can make use of the hat and frock at the weekends 😉

You haven’t met Mrs Alder! I haven’t got enough brave pills to try……….

MangoChutney

@Latimer Alder
I’d give you some of mine, but I used them all up when Mrs Alder asked me to join you for afternoon tea – needless to say, I didn’t make it. Not enough brave pills in the world

Henry Galt

Phantasists hate hardware, court told.

Brian Johnson UK

Good timing. Today the BBC are outlining, via Jonathan Amos [science correspondent] the news that the Antarctic is melting and raising the sea level.
http://www.bbc.co.uk/news/science-environment-23144184
Quotes like the one below will reassure their readers [sarc]
“The lake drainage event reported here was quite staggering in its size and the 3D image we got of the crater in the surface after the lake drained is unprecedented.”
Less than 2mm per year recorded rise for decades makes more sense to me however………

Peter Miller

Amazing what real data shows before alarmist data manipulators get at it.
What does the unmanipulated data show? Answer: Not much and absolutely nothing to be concerned about.
At the end of the day, climate alarmism is all about keeping the Global Warming gravy train on its tracks, and not much else.
The silence from the alarmist community on this subject will be deafening, as prophecies of catastrophic rises in sea levels are one of their holiest of holy grails.
Of course, Sandy proves this paper to be all wrong. Come on trolls, let’s be having you, tell us why the unmanipulated data is nonsense.

TimC

That’s it then. No acceleration in MSL (just a normal, steady, rise) implies no increase in rate of melt of land-based ice which must also imply no overall increase in arctic/antarctic temperatures (as affecting the land-based ice sheets) and no increase in the sea temperatures arriving from the middle latitudes and tropics.
Yet more proof (even for us non-scientists) that, at present, global warming simply isn’t happening – nor climate change, climate weirding or any of the other usual silly memes. We are just seeing the same old (variable, chaotic) weather we have always seen – including, sadly, that resulting in the summer wildfires in Arizona.

Old Goat

Has anyone tipped the winked to Prince Numpty Charles?

Ian W

ThinkingScientist says:
July 3, 2013 at 12:32 am
ITs strange how study after study, based on better and better methds, still seem to come up with a steady rate of sea level rise less than about 2 mm /yr. Even the IPCC reports give these figures.
And yet, year after year, the popular meme of accelerating sea level rises keeps doing the rounds. In 2001 the UK Chief Scientist announced the 6 m in 100 years claim. More than ten years on, has sea level risen the predicted 600 mm (2 ft)? Nope, just 17 mm or so.
Sea level is rising … very very slowly

The popular meme is put about by politicians who are stuck on stupid or who are mendacious malfeasants. They are ably supported in their mendacity by the ‘scientists’ of the EPA.

Perfekt

@Pat
The problems in Thailand and Vietnam are due to other causes, mainly changed land use witthout proper consideration of the inevitable rain season.
The problems in Thailand have been known for a long time and handled in the traditional Thai way, ie ignored.
I don´t expect the problem to be handled in any other way, but I wouldn´t be surprised if the Thai Government come up with something like this:http://www.gogoflorist.com/blog/2012/10/hydroponic-rice-farming-in-thailand/

Perfekt

Is the TRF-problem properly adressed in this paper? If not, what are the consequences?

Billy Liar

Brian Johnson UK says:
July 3, 2013 at 12:58 am
That BBC article should be entitled ‘Antarctic ice loss not caused by CO2′ since they admit:
These “ghost” lakes are kept in a liquid state by heat rising from the rockbed below and from the pressure of all the ice pushing down from above.
It seems that, gradually, research is finding that alarmist claims are not true.
Is anyone surprised?

izen

@-“Hence, land-water mass accumulation compensated about 20 % of the impact of ice-melt water influx to the oceans.”
So according to this study the rise in sea level over the period in question was 20% less than might have been expected because much more water accumulated on land as a result presumably from the increased rainfall from the higher humidity and increasingly active water cycle.
Either that 20% offset will cease as the floods on land drain back into the oceans, adding an extra 20% to sea level rises in the future, or the flooding seen in various areas will persist and increase as a larger proportion of the melting ice gets dumped onto land by rainfall.

Bloke down the pub

Strange, you’d have thought that if Trenberth’s heat was really hiding at the bottom of the ocean, then sea-level would be rising faster by now.

johnmarshall

Seas would rise even if there was no temperature change in the sea water and global tectonics stopped. Sedimentation still continues. Tide gauges are not a reliable measure of sea level change because they include surface level changes due to isostatic equilibrium changes.
But the fact that all reliable sea level research comes to the same conclusion– the sea level changes are small and remain fairly constant. Another myth exploded.

Billy Liar

johnmarshall says:
July 3, 2013 at 2:40 am
Tide gauges are not a reliable measure of sea level change because they include surface level changes due to isostatic equilibrium changes.
I beg to differ. Tide gauges are a direct indication of whether sea level rise actually matters.

Gamecock

You skeptics are ridiculous. You believe actual measurements, and not the models?

Jimbo

The paper corroborates the NOAA 2012 Sea Level Budget which finds sea levels have risen at only 1.1-1.3 mm/yr over the past 7 years from 2005-2012 [less than 5 inches/century],….

Yet the IPCC has told me that:

IPCC – Climate Change 2007 – AR4
Estimates for the 20th century show that global average sea level rose at a rate of about 1.7 mm yr–1.

I have also been informed that 2000 to 2009 was the “hottest decade evaaaaaah”. I have also been told that thermal expansion is surely kicking in. I have also been told that the “missing heat” is in fact no longer missing, it can be found deep sea diving. My question is a simple and genuine one:
Q) Aren’t we supposed to see an acceleration in the rate of sea level rise by now??? Or is there some longer lag time???

Gail Combs

izen says:
July 3, 2013 at 2:33 am
Either that 20% offset will cease as the floods on land drain back into the oceans, adding an extra 20% to sea level rises in the future, or the flooding seen in various areas will persist and increase as a larger proportion of the melting ice gets dumped onto land by rainfall.
>>>>>>>>>>>>>>>>>>>>>
And the plants will love it along with the added CO2 as the deserts go green

Impact of CO2 fertilization on maximum foliage cover across the globe’s warm, arid environments Randall J. Donohue et. al. – 31 May, 2013
Abstract
[1] Satellite observations reveal a greening of the globe over recent decades. The role in this greening of the ‘CO2 fertilization’ effect – the enhancement of photosynthesis due to rising CO2 levels – is yet to be established. The direct CO2 effect on vegetation should be most clearly expressed in warm, arid environments where water is the dominant limit to vegetation growth. Using gas exchange theory, we predict that the 14% increase in atmospheric CO2 (1982–2010) led to a 5 to 10% increase in green foliage cover in warm, arid environments. Satellite observations, analysed to remove the effect of variations in rainfall, show that cover across these environments has increased by 11%. Our results confirm that the anticipated CO2 fertilization effect is occurring alongside ongoing anthropogenic perturbations to the carbon cycle and that the fertilisation effect is now a significant land surface process.

FerdinandAkin

Thank Goodness sea level is still rising.
A cessation in sea level rise would be an indication the Earth is going into its next glaciation period.

Jimbo

Here is an article from last month by S. Fred Singer, professor emeritus at the University of Virginia. Is this wild speculation based on observations???

June 6, 2013
Could Global Warming Slow Sea Level Rise?
The difficulty with projections of sea level rise is nicely illustrated by the IPCC……As can be seen, the maximum SLR decreased successively as estimates improved.
As a reviewer of IPCC reports, I have been able to look at the “second order draft,” which was recently leaked to the press. It gives values of 45-110 cm (16-40 inches) — about double what IPCC estimated just six years ago in their fourth report.
In other words, sea level was rising even during the colder Little Ice age, from about 1400 to 1850 AD. This provides further support for the hypothesis that the observed global SLR since 1900 is reasonably independent of the observed temperature rise.
The data show that SLR slowed down slightly when the climate warmed and accelerated when the climate cooled.

http://www.americanthinker.com/2013/06/could_global_warming_slow_sea_level_rise.html

Whoa!!!

Jimbo

izen says:
July 3, 2013 at 2:33 am
…………..
Either that 20% offset will cease as the floods on land drain back into the oceans, adding an extra 20% to sea level rises in the future, or the flooding seen in various areas will persist and increase as a larger proportion of the melting ice gets dumped onto land by rainfall.

Or we can stop adding to sea level rise by stopping our extraction of water from below ground.
Dams V Boreholes

Large-scale groundwater extraction for irrigation, drinking water or industry results in an annual rise in sea levels of approximately 0.8 mm, accounting for about one-quarter of total annual sea-level rise (3.1 mm). According to hydrologists from Utrecht University and the research institute Deltares, the rise in sea levels can be attributed to the fact that most of the groundwater extracted ultimately winds up in the sea. The hydrologists explain their findings in an article to be published in the near future in the journal Geophysical Research Letters.”
http://www.uu.nl/EN/Current/Pages/Wereldwijdonttrekkenvangrondwaterleidttotzeespiegelstijging.aspx

Izen, unless observations show acceleration, I wouldn’t lose any sleep over this crap. Relax.

spangled drongo

The supermoon last month produced the highest astronomical tide of the year at our place on the east coast of Australia and the level it achieved was exactly what it was 60 years ago.
2inches above the old sea wall built to AHD 1.1
Not much SLR here.

Here is the Sydney (Fort Dension) NSW Aust. records since 1914 http://www.bom.gov.au/ntc/IDO70000/IDO70000_60370_SLD.txt . Can you see any statistical increase? This monitoring site has one of the longest recorded records of tides and sea level.in the world.

Wait a minute. Predictions for the the East Coast of the US is 2 feet by 2050. Some explanations is the SLR is exponential so we won’t see it for a couple of decades. These models are accepted by a consensus of scientists so they can’t be wrong. Don’t confuse me with data.

izen

@- Gail Combs
“And the plants will love it along with the added CO2 as the deserts go green”
IF it falls on the deserts.
Recent fooding in India, Canada and the Midwest indicates that the extra rain has not always arrived in a manner that improves agricultural yields.
Sometimes quite the opposite.
http://www.swnews4u.com/section/1/article/14298/

Paul80

Along side the abstract of the paper is this information:
GMSL Rates: CU: 3.2 ± 0.4 mm/yr AVISO: 3.2 ± 0.6 mm/yr
CSIRO: 3.2 ± 0.4 mm/yr NOAA: 3.2 ± 0.4 mm/yr (w/ GIA)
Yet as this paper concludes and as Jimbo (above) quotes:
IPCC – Climate Change 2007 – AR4
Estimates for the 20th century show that global average sea level rose at a rate of about 1.7 mm yr–1.
Will someone explain this discrepancy? Or are these GMSL rates just plain alarmist exaggeration?

Geoff Sherrington

This was embargoed when I last inquired, but do go to Climate Audit, find the thread Econometric Applications in Climatology and futz around for a paper by Beenstock, Felsenstein, Frank & Reingewertz in the conference program guide. It’s but a couple of weeks old.
Re co-author of the cited Baur, O., Kuhn, M. and Featherstone, W.E. 2013. Continental mass change from GRACE over 2002-2011 and its impact on sea level. Journal of Geodesy 87: 117-125.
Will Featherstone was at Curtin University, West Australia, Surveying, so the paper will be of impeccable quality.

Bill Illis

In other words, billions of dollars were wasted putting 5 different sea level measuring satellites into orbit because the scientists who collated the raw data just added 1.4 mms/yr to the numbers because of their belief systems.
The science has a rotten tendency to do this with all base climate data.
It wouldn’t be that big of a problem if we weren’t changing our whole civilization based on these belief-driven adjustments.

Doesn’t the graphic show the coriolis effect and that water is just sloshing around under lunar orbital influence? They presume lunar influence is smoothed out over 29.5 days but ignore numerous important cycles including 18.11 year Saros Cycle, 18.6 year Nodal Cycle, 19 year Metonic Cycle.

izen

@- Paul80
“Along side the abstract of the paper is this information:
GMSL Rates: CU: 3.2 ± 0.4 mm/yr AVISO: 3.2 ± 0.6 mm/yr
CSIRO: 3.2 ± 0.4 mm/yr NOAA: 3.2 ± 0.4 mm/yr (w/ GIA)
Estimates for the 20th century show that global average sea level rose at a rate of about 1.7 mm yr–1.
Will someone explain this discrepancy? Or are these GMSL rates just plain alarmist exaggeration?”
The 1.7mm/yr is the long term average over {at least} the last fifty years.
The 3.2mm/yr is the satellite measurement over the recent past.
This is why some scientists are claiming that the rate of sea level rise has doubled and the AR4 estimates are far too low as well as omitting the contribution from increasing ice melt.

William Astley

This is a significant finding.
As there is no change in the rate of rise of the oceans’ level supports the assertion that heat cannot be hiding in the oceans.
The fact that there was been 16 years of no change in planetary temperature appears to indicate that there is/are one or more fundamental errors with the greenhouse gas warming mechanism in addition to the fact that the planet resists forcing changes (negative) feedback rather than amplifying forcing changes.

Richie

Can somebody tell me whether the present state of England’s Cinque Ports, which are now high and dry but were at sea level in medieval times, was caused by retreating sea level or by upthrusting of the terrain?

izen

@- Bill Illis
“It wouldn’t be that big of a problem if we weren’t changing our whole civilization based on these belief-driven adjustments.”
The ‘belief’, which is rather well supported by empirical observations, is that the changing climate will impose far worse changes on our whole civilisation and that the intelligent thing to do is prevent as much of the change as possible and adapt to the unavoidable damage the present changes are causing.
This is an alternative to propagating the belief that the scientific case for mitigation and adaption is a political conspiracy. With the consequent Panglossian inference that the status quo is the best of all possible worlds….

John Peter

Where does that leave the University of Colerado with their 3.2mm +/- 0.4mm per year?
http://sealevel.colorado.edu/
Maybe their various “corrections” account for their near doubling of the annual rate.
Maybe they would like to comment here. No chance.

You can squeeze a tennis ball in your hand.So does the Earth naturally expand and contract with sissmic activity under the oceans and on the coasts .So how does that make the sea level appear to go up and down.

izen

@- Richie
Can somebody tell me whether the present state of England’s Cinque Ports, …
Old Whinchelsea is now underwater, but the other Cinque ports were river ports which have silted up as a result of river sediments and coastal deposition from the channel tidal eastward drift.
The tectonic changes have mainly been glacial rebound in the North causing subsidence in the south, but this has not been sufficient to offset the rise in coastal land from sedimentation on the English south coast.

Bill Illis

The tide gauges on average are measuring 1.4 mms/yr of sea level rise. [Because the coastlines are rising by 0.3 mms/yr due to ice age rebound and general continental drift changes, one could argue that the volume of sea level is rising at 1.7 mms/yr, but it is only 1.4 mms/yr where we live on land and that is what matters. I guess it might matter more to islands which are anchored to the ocean crust but these islands at risk are not generally in the locations where the majority of ice age rebound is occuring, causing the ocean crust to sink back – just a few which are also on continental shelf margins in the lower latitudes].
For unknown reasons, the satellite raw data adjustment algorithms have sea level rise at 2.9 mms/yr (and 0.3 mms/yr is added for the average land rise versus the ocean depth).
I downloaded all the tide gauge data from the Permanent Mean Sea Level Service (PMSL) and the average is rising at just 1.4 mms/yr (now this is the average of all guages in the database – it will not be a true mean sea level rise because there will be individual gauges moving into and out of the database each year but there are just so many at any one time, its hard to imagine how this fact could change the trend, but caveat required].
All 31,000 annual tide gauge observations going back to 1807. [Note there are some general groups that are rising quickly and some groups that are falling but this is due to ice age rebound where some geographic places are rising at 10 mms/yr for example but other locations are falling at 3.0 or 4.0 mms/yr].
On average since 1807, the tide guages are increasing by 0.28 mms/yr.
http://s17.postimg.org/si6ly8q27/Sea_Level_Measurements_PMSL.png
If we zoom into the 1930 to 2009 period, we see that the general trend remained at 0.29 mms/yr until about 1980. (A possible 60 year cycle impacting it). After 1980, the trend rises to 1.4 mms/yr. I don’t see any acceleration in this rate since 1980.
http://s2.postimg.org/xcp9tsz6x/Sea_Level_Measurements_PMSL_1930_1980_2009.png
Now compared to some other sea level reconstructions including the satellite altimetry outlier.
http://s8.postimg.org/9ysbkpw51/All_Sea_Level_Measurements_1960_2013.png

@pat
By reading first Potsdam report at the beginning, I found this sentence:
„The present CO2 concentration is higher than paleoclimatic and geologic evidence indicates has occurred at any time in the last 15 million years.”
The “reference” the report I found only one work on the subject – A.K. Tripati of 2009. Since that time was established, however, some fundamental papers (which should be of interest to the authors of the report) saying (at least partly) different than the A.K.T., for example, Pagani (2010) and especially Seki (2010. Alkenone and boron-based Pliocene pCO2 records)
Recently work Tripati has once again been strongly confounded (http://www.ldeo.columbia.edu/~polissar/teaching/F2012_G9600_Climate_Puzzles_of_the_Neogene/LaRiviere_etal_2012_Suppl.pdf): “… we consider it premature to apply the B/Ca to long (myr) reconstructions of past pCO2, as Tripati et al.9 did. For these reasons, we have excluded the abovementioned records from Figure 1. However, the uncertainties associated with these estimates are too large to constrain the pCO2 changes of the past 15 myrs. For this reason we have excluded these estimates from Figure SI 1 and Figure 1.”
Of course, this figure is worth seeing …
The last Potsdam report threaten us heat waves and tropical cyclones (as a result of global warming).
The current warming should be comparable to the Eemian – Sangamon and Holocene maximum.
Eemian and mid-Holocene (6,000 years ago and the last interglacial period 125,000 years ago – http://blog.chron.com/climateabyss/2011/12/dispatch-from-agu-an-equable-climate-curveball/).
“So in both seasons [mid-Holocene 6,000 years ago and the last interglacial period 125,000 years ago], the detectable segment of the pole-to-equator temperature difference was smaller than at present, and at high latitudes the seasons were less dramatic than at present.”
“According to Davis and colleagues, the higher latitude continents north of 50N in both periods [max. Eemian, mid-Holocene] were much warmer than present-day climate in winter, not so much warmer in summer. “Climate models don’t do this.” „… they are generally too warm on summer …”
It is now time for my “cherry”:
Tom Knutson (2008, 2013 – http://www.gfdl.noaa.gov/global-warming-and-hurricanes/) write:
“Turning to future climate projections, current climate models suggest that tropical Atlantic SSTs will warm dramatically during the 21st century, and that upper tropospheric temperatures will warm even more than SSTs. Furthermore, most of the models project increasing levels of vertical wind shear over parts of the western tropical Atlantic (see Vecchi and Soden 2007). Both the increased warming of the upper troposphere relative to the surface and the increased vertical wind shear are detrimental factors for hurricane development and intensification, while warmer SSTs favor development and intensitification. To explore which effect of these effects might “win out”, we can run experiments with our regional downscaling model.”
Is the experiments are necessary?
Soelen (2012, http://hol.sagepub.com/content/early/2012/02/28/0959683611434226.abstract): „Throughout the record, indications for storm activity can be recognized as coarser grained layers consisting of quartz sands or shell debris. These layers are rare during the mid Holocene [warm period], but between 3.2 and 2 kyr BP [cool period], their numbers increase, suggesting an increase in tropical cyclone activity in the Gulf of Mexico.”
The most frequent changes in the amplitude of the global sea level is 70-75 cm (Holocene).
… but Southeast Asia during the Holocene natural repeatedly experienced much more sudden changes in sea level. Worth reading this work:
Holocene weak summer East Asian monsoon intervals in subtropical Taiwan and their global synchronicity (Selvaraj, 2008): “… believed to be driven by coupled ocean-atmosphere interactions, especially reduced heat and moisture transport and enhanced El Nin˜o-Southern Oscillation in the tropical Pacific, as well as solar activity.” What causes: “… abrupt changes witnessed in other paleorecords …”
Conclusion: Reports Potsdam is a typical example of an alarmist “cherry picking” in its extreme form – an opportunistic use of science to economic and political objectives.
The question therefore arises: will prepare infrastructure shores of South East Asia (for the change), or perhaps the same money spent fuel concerns in geo-sequestration of CO2 – as it does (and want to do more of it) UN and EU?

Steve Case

If you got to the Internet Archive’s WayBack Machine:
http://archive.org/web/web.php
and plug in the URL for Colorado Universty’s Sea Level Research Group
http://sealevel.colorado.edu/
You will find records that go back to 2004
The earliest functional “mean sea level time series” link is from
March 27th of that year, and if you follow that link through to “Inverted Barometer Applied” and “Seasonal Signals Removed” and click on text
http://web.archive.org/web/20040413231515/http://sealevel.colorado.edu/2004_rel1.2/sl_ib_ns_cu2004_rel1.2_global.txt
you will find the data as it existed for 1992.928 thru 2003.842 It’s then rather simple to download the series into Excel and find the slope. It comes out to be 2.6 mm/yr
If you then go to Colorado University’s Sea Level Research Unit today and dowload the “Raw data (ASCII)”
http://sealevel.colorado.edu/files/2013_rel4/sl_ns_global.txt
You will find that the same series for 1992.96 through 2003.846 comes out to be 3.5 mm/yr
Somehow over the last ten years the data has been changed. What had been 2.6 mm/yr in 2003 is now 3.5 mm/yr. An increase of 0.9 mm/yr.
If you ask Colorado University about these changes they say:

The sea level time series release from 2004 is over eight years old, and in that time many parts of the TOPEX and Jason-1 processing have been updated to reflect instrument and ancillary data improvements. Without recreating each processing change over the last eight years, We cannot point to any specific update that is the main cause of the differences between the 2004 and the current release. But a partial list of the more influential updates include:
– updated orbits
– updated radiometer corrections
– updated tide models
– updated sea state bias models
– updated dynamic atmosphere
A review of the release notes shows how we continually apply what the altimeter science community considers to be the most up-to-date set of processing parameters.

Without further comment the above stands as its own testimony.

stacase

If you got to the Internet Archive’s WayBack Machine:
http://archive.org/web/web.php
and plug in the URL for Colorado Universty’s Sea Level Research Group
http://sealevel.colorado.edu/
You will find records that go back to 2004
The earliest functional “mean sea level time series” link is from
March 27th of that year, and if you follow that link through to “Inverted Barometer Applied” and “Seasonal Signals Removed” and click on text
http://web.archive.org/web/20040413231515/http://sealevel.colorado.edu/2004_rel1.2/sl_ib_ns_cu2004_rel1.2_global.txt
you will find the data as it existed for 1992.928 thru 2003.842 It’s then rather simple to download the series into Excel and find the slope. It comes out to be 2.6 mm/yr
If you then go to Colorado University’s Sea Level Research Unit today and dowload the “Raw data (ASCII)”
http://sealevel.colorado.edu/files/2013_rel4/sl_ns_global.txt
You will find that the same series for 1992.96 through 2003.846 comes out to be 3.5 mm/yr
Somehow over the last ten years the data has been changed. What had been 2.6 mm/yr in 2003 is now 3.5 mm/yr. An increase of 0.9 mm/yr.
If you ask Colorado University about these changes they say:

The sea level time series release from 2004 is over eight years old, and in that time many parts of the TOPEX and Jason-1 processing have been updated to reflect instrument and ancillary data improvements. Without recreating each processing change over the last eight years, We cannot point to any specific update that is the main cause of the differences between the 2004 and the current release. But a partial list of the more influential updates include:
– updated orbits
– updated radiometer corrections
– updated tide models
– updated sea state bias models
– updated dynamic atmosphere
A review of the release notes shows how we continually apply what the altimeter science community considers to be the most up-to-date set of processing parameters.

Without further comment the above stands as its own testimony.

MikeN

But they didn’t account for Rahmstorf’s calculation of an acceleration of sea level presently visible.

Richard M

I wouldn’t think the TRF problem is not pertinent here since it is comparing GRACE data to GRACE data. And, unlike the silly claims of Izen, the 2002-2011 period makes this quite recent.
The water being pumped out of aquifers is probably much more than any increases to land water. This would mean the actual rise is much less (maybe half as much).
I got a kick out of Izen’s silly mentioning of floods in the Midwest US since that is the very region that had a drought last year. The average of the two years is right around normal.
Does anyone else get the feeling that Izen is in full panic. The pure denial in all his comments is extraordinary.

Richard M

Typo .. s/b “I would think …”

John Mason

A truly objective observer would conclude, quite simply, from the combination of tidal gauge data and confirmation of the Grace data, that there is no effect from the increase in CO2 on the natural rate of change coming out of the little ice age.

catweazle666

Which somewhat begs the question of how the “Missing Heat” that seems to have eluded Kevin and Co. since ~1997, and having, despite the laws of convection, managed to slink undetected through the – cooling since the beginning of the century – sea surface, has managed to sequester itself the deep oceans, without managing to cause any overt or accelerated expansion.
Clever stuff, this climate science.