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

  1. 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……

  2. 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

  3. 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

  4. @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……….

  5. @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

  6. 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………

  7. 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.

  8. 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.

  9. 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.

  10. @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/

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

  12. 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?

  13. @-“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.

  14. 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.

  15. 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.

  16. 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.

  17. 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???

  18. 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.

  19. 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.

  20. 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!!!

  21. 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.

  22. 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.

  23. 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.

  24. @- 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/

  25. 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?

  26. 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.

  27. 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.

  28. 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.

  29. @- 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.

  30. 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.

  31. 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?

  32. @- 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….

  33. 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.

  34. 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.

  35. @- 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.

  36. 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.

    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.

    Now compared to some other sea level reconstructions including the satellite altimetry outlier.

  37. @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?

  38. 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.

  39. 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.

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

  41. 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.

  42. 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.

  43. 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.

  44. This paper essentially confirms results found by other people.

    A major problem in using just the 9-year period of May 2002 to April 2011 is that sea levels are affected by decadal and multidecadal climatic oscillations. And during the last 10-20 year the acceleration in SLR has normally been negative.

    in my recent publications there is a extensive discussion on these topics:

    Scafetta N., 2013. Multi-scale dynamical analysis (MSDA) of sea level records versus PDO, AMO, and NAO indexes. Climate Dynamics. in press. DOI: 10.1007/s00382-013-1771-3.

    http://link.springer.com/article/10.1007%2Fs00382-013-1771-3

    Scafetta N., 2013. Discussion on common errors in analyzing sea level accelerations, solar trends and global warming. Pattern Recognition in Physics, 1, 37–57. DOI: 10.5194/prp-1-37-2013.

    http://www.pattern-recogn-phys.net/1/37/2013/prp-1-37-2013.html

    Papers can be downloaded from my web-site.

  45. Richard M says:July 3, 2013 at 7:49 am
    You make some good points. I was considering wasting a post in izen asking if he had heard of land-based aquifers, which probably need recharging form all the irrigation we pull out. So his fantasy of all the rainwater running back into the oceans is moot. Speaking of aquifers, if one uses the numbers provided by the UN for the amount of water used in irrigation, which admittedly may not be good numbers, just our irrigation water, if all went to the seas, would be over 2mm/year of SL rise.

  46. izen says:
    July 3, 2013 at 4:54 am

    @- 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.

    Does the greening of the Sahel count? Now let’s go global.

    May 2013
    Abstract
    A Global Assessment of Long-Term Greening and Browning Trends in Pasture Lands Using the GIMMS LAI3g Dataset

    Our results suggest that degradation of pasture lands is not a globally widespread phenomenon and, consistent with much of the terrestrial biosphere, there have been widespread increases in pasture productivity over the last 30 years.

    http://www.mdpi.com/2072-4292/5/5/2492

    10 APR 2013
    Abstract
    Analysis of trends in fused AVHRR and MODIS NDVI data for 1982–2006: Indication for a CO2 fertilization effect in global vegetation

    …..The effect of climate variations and CO2 fertilization on the land CO2 sink, as manifested in the RVI, is explored with the Carnegie Ames Stanford Assimilation (CASA) model. Climate (temperature and precipitation) and CO2 fertilization each explain approximately 40% of the observed global trend in NDVI for 1982–2006……

    http://onlinelibrary.wiley.com/doi/10.1002/gbc.20027/abstract

  47. izen says:
    July 3, 2013 at 5:47 am

    @- 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.

    Events have just overtaken your belief system. Upstream, just reported on WUWT

    U.N. World Meteorological Organization report pans the idea that severe weather and severe weather deaths can be linked to climate change

    “…..There were fewer deaths, even while exposure to extreme events increased as populations grew and more people were living in disaster-prone areas. According to the 2011 Global Assessment Report, the average population exposed to flooding every year increased by 114 per cent globally between 1970 and 2010, a period in which the world’s population increased by 87 per cent from 3.7 billion to 6.9 billion. The number of people exposed to severe storms almost tripled in cyclone-prone areas, increasing by 192 per cent, in the same period……”

    http://wattsupwiththat.com/2013/07/03/u-n-world-meteorological-organization-report-pans-the-idea-that-severe-weather-and-severe-weather-deaths-can-be-linked-to-climate-change/

  48. izen says:

    July 3, 2013 at 5:47 am

    @- 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….
    <<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>
    Typical knee-jerk alarmism. What “change in climate”, pray tell? In fact, there has been none.

  49. Jimbo says-

    “10 APR 2013 Abstract
    Analysis of trends in fused AVHRR and MODIS NDVI data for 1982–2006: Indication for a CO2 fertilization effect in global vegetation”

    Thank you for posting this link. The pdf is available for no charge.

    This is really important, because it provides a means of estimating how many people are being fed by CO2 emissions simply through fertilization. If it is included in any estimate of CO2 impacts, the result will be an overwhelming positive impact, assuming that the value of $7M to $9M per human life is used for both costs and benefits of burning fossil fuels.

    Unfortunately, the people who want to stop CO2 emissions are the same ones who want global population truncated to 1 Billion or less. They count increased food production as a negative.

  50. John Peter says:

    July 3, 2013 at 5:53 am

    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.
    <<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>

    The U of Colo sea level studies are completely fanciful. They will never respond to any critique on WUWT because they would get clobbered. Better to sit quiet and rake in the public’s money.

  51. There are various factors that alter sea level
    1- thermal expansion or contraction
    2- loss or gain in land based ice
    3- loss or gain in land based aquifers from rainfall

    As Nicola mentioned short term variations climate variation can alter any underlying trend. The recent extra rainfall seen and subsequent flooding caused the reduction in the rate of sea level rise seen in 2011/2012 as part of the 1 metre {about a yard} of water evaporated each year from the oceans was retained on the land. Most will eventually return to the oceans, but some will refill aquifers depleted by human extraction.

    The thermal expansion and loss of land based ice mass can be measured with errors less than the measurement. But the balance of rainfall and aquifer retention or return to the oceans are much more uncertain and can alter the underlying rate of sea level rise significantly.

    However unless there is a dramatic reversal of the thermal expansion or the negative ice-mass balance the influence of rainfall variations can only be short-term and transient. I don’t think any knowledgable oceanographer would claim that the glaciers and Greenland ice cap are suddenly going to gain mass or that the oceans will cool and contract in the next century given the energy imbalance caused by the increased CO2.
    That commits human society to adapting to several feet of sea level rise by the end of the century. That MAY be a slow enough change to adapt to. But it will be a new situation that human societies have not faced in recorded history as there is good evidence, geological, archeological and astronomical, that there has never been any similar significant change in sea level in the past six thousand years.
    All the great coastal cities and communities have developed over human history with a very stable sea level.
    That has now changed.

  52. “Finds sea levels have risen over the past 9 years [2002-2011] at a rate of only 1.7 mm/yr”

    Oops. Bit of discrepancy here. Sea Level Research Group at University of Colorado shows 2.4 mm/yr for the same period (41% higher), AVISO 2.6 mm/yr (53% higher).

    Disagreement can’t easily be ignored, as this value is well outside error bars. Are current calibration methods of satellite altimetry useless?

  53. @paul80:

    Most of the sea level rise data you see, included those cited at left, are from “altimetry” satellites. These measure the distance between themselves and the surface. The biggest wild card in these measurements is the how well the height of the orbit of these satellites is known. This height certainly isn’t known directly to mm/year accuracy or even resolution, so it must be inferred indirectly.

    I have yet to find direct explanation of how this calibration process works. Indirect explanations I have seen say that the trends altimeter satellite data is compared to terrestrial tide-gauge data at specific places around the globe, and that the difference is attributed to orbital changes. These calculated orbital changes are then used to convert the raw “distance” data into “sea level” data.

    However, the tide-gauges worldwide have generally show trends under 2mm/year both before and after the altimetry satellites went up. That’s why arguments that the trends used to be 1.7mm/year and are now 3.2mm per year, as put out by the IPCC (in their summaries; if you read their whole reports, they qualify this), and parroted by folks like izen, are so misleading.

    The question is how well they have done this calibration process, and with what error bars they have done it. If the calibration is off by 1.5mm/year (and I think it easily could be), then these different figures are brought into line.

    Check out the first link in the article. That describes an analysis by NOAA scientists to rectify three different data sets: the satellite altimetry, the GRACE gravity satellite data, and the ARGO buoy ocean thermal data. Combining these, they find a best estimate of 1.1 – 1.3 mm/year sea level rise so far this century.

  54. izen says:
    July 3, 2013 at 12:00 pm
    ////////////////////////
    Have you seen the many Greek ports in the Med and Aegean which are now high and dry? In some places, the sea is approximately 50km from where it was at the height of the Greek and Roman Empires.

    You only have to go along the Thames to see that in Tudor times and indeed in the 18th/early 19th century the river levels (the Thames is a tidal river) were much higher. In Tudor times, the Tower of London was approached via the river, but water level are now to low to permit boats to enter.

    the statement “All the great coastal cities and communities have developed over human history with a very stable sea level.” does not bear scrutiny when viewed against historical and archaelogical evidence.

  55. Hansen’s flooded West Highway along the Hudson R in 15 years prediction made in 1986 and then increased to 40 years upon expiry – man there is no end to the hubris of the faithful. The highway is ~10 feet above the river – this is the basis for his recent 20 foot rise prediction by 2100. That sucker is going to be 10 feet under! I think with the declining climate sensitivity from 4-6 down to <1, sea level (apart from the 20 feet said in anger) down from 3m to 7 inches we can soon construct an exaggeration index that might be useful.

  56. Berényi Péter at 1:11 pm said
    “Finds sea levels have risen over the past 9 years [2002-2011] at a rate of only 1.7 mm/yr”

    Oops. Bit of discrepancy here. Sea Level Research Group at University of Colorado shows 2.4 mm/yr for the same period (41% higher), AVISO 2.6 mm/yr (53% higher).

    Disagreement can’t easily be ignored, as this value is well outside error bars. Are current calibration methods of satellite altimetry useless?
    ****************
    If you take the data as published at the time, “2011 rel_1″

    http://sealevel.colorado.edu/files/2011_rel1/sl_ns_global.txt

    and then calculate the slope from 2002 forward you will wind up with:

    Slope 2002.0269 to 2011.09 yields 2.27mm/year

    And since CU adds in a GIA adjustment of 0.3 mm/yr so that their sea level chart will be a proxy for ocean volume, that needs to come out, so you wind up with less than 2 mm/year. They’ve made other corrections and modifications over the years, so I expect that 1.7 mm/yr isn’t too far off the mark.

  57. Question: As the temperatures have leveled off or dropped in the last decade, will that decrease the rate of the rise??

  58. Interesting that the data appears to be converging at about 15 cm by 2100. I recall Dr Morner’s recent finding of 5 inches by 2100 from tidal gauge records.

    I suspect projections will be revised even lower as the solar minimum really starts to kick in.

    Now if someone could convince my excitable local city council that they don’t have to scare people witless and devastate our house prices with sea level hysteria, it would be nice.

  59. Paul80 says: July 3, 2013 at 5:16 am
    “Will someone explain this discrepancy? Or are these GMSL rates just plain alarmist exaggeration?”

    Is there really a discrepancy at all?
    Despite the headline of this post, the paper does not really make a finding about GMSL rise. It is a paper about mass gain. A part of GMSL rise is the steric (thermal/salinity) component, and here is what they say:
    “In summary, at present steric sea-level change computation is subject to large uncertainty. In order to provide some numbers regarding the total sea-level change, adding the steric component of +(0.5 ± 0.5) mm/year (Leuliette and Willis 2011) to our non-steric ocean mass trends yields +(1.6 ± 0.8) mm/year (geocentre neglected) and +(1.7±0.8) mm/year (geocentre corrected).”
    The “In summary” refers to a listing of some fairly divergent steric expansion results. I wouldn’t say that this statement, as phrased, is meant to be a “finding”.

    But anyway it’s hard to argue that these results trump the direct satellite altimetry observations. They are created by adding together a lot of uncertain components of a budget, of which, as they say, the estimated steric component is very uncertain indeed. The component analysis is certainly interesting.

  60. @stacase

    “””””…..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. …..”””””

    news today says Jason-1 was just executed, but is going to swing in orbit for 1,000 years, just to make more space clutter.

    In its 11 1/2 year life, it recorded 1.6 inches (4.0 cm) of sea level rise; well “within a few cm”, like maybe 4 cm. so between zero and 8 cm in 11 1/2 years. really useful to know that.

  61. stacase says:
    July 3, 2013 at 1:41 pm

    If you take the data as published at the time, “2011 rel_1″

    http://sealevel.colorado.edu/files/2011_rel1/sl_ns_global.txt

    and then calculate the slope from 2002 forward you will wind up with:

    Slope 2002.0269 to 2011.09 yields 2.27mm/year

    And since CU adds in a GIA adjustment of 0.3 mm/yr so that their sea level chart will be a proxy for ocean volume, that needs to come out, so you wind up with less than 2 mm/year. They’ve made other corrections and modifications over the years, so I expect that 1.7 mm/yr isn’t too far off the mark.

    Well, that’s the issue with consecutive revisions being adjusted ever upward. Here are 2011_rel1 & 2013_rel4. Trend in the former one is indeed 2.27 mm/yr from (beginning of) 2002 to (beginning of) 2011, as you claim, but in the latter one it is 2.4 mm/yr from (beginning of) 2002 to (end of) 2011.

    You can see retrospective adjustments done between the two releases in both textual & graphics format.

    These adjustments are pretty flat (albeit noisy) up to 2002, but after that hell is getting loose.

    You are of course right about the GIA adjustment of +0.3 mm/yr being added to Colorado stuff, but that’s preposterous in itself, since it has nothing to do with sea level as such. If they have meant ocean volume, they should have used that term, not another, misleading one.

    Anyway, if GIA is subtracted, one is left with 1.97 mm/yr & 2.1 mm/yr in 2011_rel1 & 2013_rel4 respectively, 16% / 24% higher than this current estimate based on GRACE.

    There is some splainin’ to be done indeed. Specifically, why & how later releases have made the estimate worse, not better?

  62. This is interesting. An observational indication that the planet is starting to cool is a reversal of the polar see saw. The planet warms and cools cyclically correlating with solar magnetic cycle changes, The solar magnetic cycle activity was the highest in 8000 years for the duration of the current warming period. The solar magnetic cycle has abruptly slowed down and there are observational indications that the sun will be anomalously spotless by the end of the year.

    When the planet as a whole cools, due to what causes the polar see saw, the Antarctic ice sheet warms which results in increased snow fall on the Antarctic ice sheet.

    http://www.cato.org/blog/long-awaited-snowfall-increase-antarctica-now-underway

    A paper to soon appear in Geophysical Research Letters give us another enticing look at recent snowfall changes in Antarctica. In “Snowfall driven mass change on the East Antarctic ice sheet,” Carmen Boening and colleagues from NASA’s Jet Propulsion Laboratory report that extreme precipitation (snowfall) events in recent years (beginning in 2009) have led to a dramatic gain in the ice mass in the coastal portions of East Antarctica amounting to about 350 Gt in total (Figure 1).

  63. Billy Liar is confused.
    I did not mean that Tide Gauges were not giving reliable data but for a locality only not for a large area or to calculate the global sea level rise accurately. They only give relative sea level changes at that gauge position.

  64. johnmarshall says:
    July 4, 2013 at 2:56 am

    I’m not confused. I agree with you on the wider issue of global sea level. The point I was trying to make is that relative sea level is what’s important to you when you go to the beach or decide whether to build a house by the sea.

  65. Way out of my hobby’s area of interest but.. while doing a continued search on the Van Allen Radiation Belts I inevitably began coming across the South Atlantic Magnetic Anomaly references in articles.
    Vuks will be pleased with the article I’m sure.

    Now these guys know that correlation does not mean cause and put it to the tests..the article is not from Colorado heh..
    The correlation also includes temp.
    An interesting theory about the SAMA area beneath sea on the ocean floor rising and falling due to outer core processes. (counter clockwise rotation in outer core)

    Geomagnetic South Atlantic Anomaly and global sea level rise: A direct
    connection?
    A. DeSantis a,b,n, E.Qamili a,c, G.Spada d, P.Gasperini e
    a Istituto NazionalediGeofisicaeVulcanologia,SezioneRoma2,Rome,Italy
    b Universita ‘‘G.D’Annunzio’’,CampusUniversitario,Chieti,Italy
    c Scuola diDottoratoinScienzePolari,Universita deglistudidiSiena,Siena,Italy
    d Dipartimento diScienzediBaseeFondamenti,UrbinoUniversity‘‘CarloBo’’,Urbino,Italy
    e Dipartimento diFisica,SettoreGeofisica,Universita diBologna,Bologna,Italy

    Abstract
    We highlight the existence of an intriguing and to date unreported relationship between the surface area of the South Atlantic Anomaly (SAA) of the geomagnetic field and the current trend in global sea level rise. These two geophysical variables have been growing coherently during the last three centuries, thus strongly suggesting a causal relationship supported by some statistical tests. The monotonic increase of the SAA surface area since 1600 may have been associated with an increased inflow of radiation energy through the inner Van Allen belt with a consequent warming of the Earth’s atmosphere and finally global sea level rise. An alternative suggestive and original explanation is also offered, in which pressure changes at the core–mantle boundary cause surface deformations and relative sea level variations. Although we cannot establish a clear connection between SAA dynamics and global warming, the strong correlation between the former and global sea level supports the idea that global warming may be at least partly controlled by deep Earth processes triggering geomagnetic phenomena, such as the South Atlantic Anomaly, on a century time scale.

    Highlights

    ► We compare South Atlantic Anomaly (SAA) surface and sea level in the last 300 years. ► SAA and sea level show a strong correlation supported by statistical tests. ► Increasing the SAA surface may have increased the inflow of radiation energy. ► The radiation energy may have warmed the atmosphere causing the sea level change. ► Alternatively magnetic field and sea level changes may have a common internal cause
    ftp://ftp.ingv.it/pro/terrasol/space/DeSantis_et_al_JASTP_2012.pdf

  66. Off topic but..
    Wondering if Stephen Wilde has seen this article?

    Observations of nitric oxide in the Antarctic middle atmosphere during recurrent geomagnetic storms

    Newnham, D. A.; Espy, P. J.; Clilverd, M. A.; Rodger, C. J.; Seppälä, A.; Maxfield, D. J.; Hartogh, P.; Holmén, K.; Horne, R. B.

    EGU General Assembly 2012, held 22-27 April, 2012 in Vienna, Austria., p.5445
    Abstract
    ..Electrons in the range 10 keV to several MeV precipitate from the radiation belts in the subauroral zone at geomagnetic latitudes ≤ 75° , and particularly in the southern hemisphere and pole-ward of the South-Atlantic Magnetic Anomaly (SMA). Although in general the precipitating flux decreases rapidly with increasing electron energy this mechanism can produce NOx directly in the stratosphere and mesosphere. To establish high-latitude NOx production throughout the polar night, follow its transport, and determine its effects on the composition and chemistry of the mesosphere and stratosphere we have developed and deployed a 230-250 GHz passive microwave radiometer in Antarctica to observe NO, ozone (O3), and carbon monoxide (CO). Here we report ground-based measurements made from Troll station (72° 01’S 02° 32’E, geomagnetic latitude 65° ), a location equator-ward of the auroral zone, pole-ward of the area of radiation belt precipitation and the SMA, and deep within the polar vortex during the Austral winter. Our observations show enhanced mesospheric NO volume mixing ratio (VMR) reaching 1.2 ppmv at 65-80 km during a series of small recurrent geomagnetic storms in the 2008 polar autumn and winter. The Lomb normalized periodogram of the NO VMR time series averaged over 65-80 km for days 80 to 220 of 2008 (20 March to 7 August) shows a peak exceeding the 95% confidence limit at 27 days, matching the solar rotation period. For 2008 days 80 to 129 the radiometer NO VMR data is moderately correlated (r = 0.67, lag time of 0.9 days) with 90° telescope “trapped” electron count rate for the >300 keV channel of the SEM-2 MEPED instrument onboard the low altitude (300 keV electron count rate and a longer lag time of 4-5 days. The altitude profile of mesospheric NO, and ionisation data for the lower ionosphere from 30 MHz and 51.4 MHz widebeam riometers at SANAE IV station (71° 40’S, 02° 51’W) and the AARDVARK (Antarctic-Arctic Radiation-belt (Dynamic) Deposition – VLF Atmospheric Research Konsortium) network, suggests mesospheric NO is produced by ~100-300 keV electron precipitation with significant downwards transport in the southern-hemisphere winter-time polar vortex.

    http://adsabs.harvard.edu/abs/2012EGUGA..14.5445N

  67. Sea level change from 2005 – 2011? There is 22 years of sea level data from the satellites. Why be satisfied with cherry-picking a subset? You need much more data to discern an acceleration with statistical significance.

    No statistical significance testing on acceleration. No meat to the argument.

    Heck, if time period doesn’t matter, I could choose 2011 to present – a massive acceleration in sea level rise – but my point would be as specious as the above.

  68. How much environmental risk is from these factors? I think every person in this planet should know about these. Let us share. Good thing you posted it here.

  69. If you search around on the Colorado University Sea Level Research Group site, you will eventually run across the fact that they calibrate the satellites against a group of 64 tide gauges.

    I’m having trouble finding out what those 64 PSMSL gauges are. if they are PSMSL gauges.

    Does anyone know?

  70. barry said July 6th at 6:02 am

    Sea level change from 2005 – 2011? There is 22 years of sea level data from the satellites. Why be satisfied with cherry-picking a subset? You need much more data to discern an acceleration with statistical significance.

    Data sets from 2011 and newer can be found on the CU Web Page
    For example here’s 2013 Release 4

    Older data can be found on the Internet Archives WayBack Machine
    For Example here’s 2004 Release 1.2

    If you take the slope (mm/yr) of the same time series 1992.9 – 2003.8 from both of those time series, you will find that over the past decade the slope has been bumped up from 2.6 mm/yr to 3.5 mm/yr. Do you ever wonder how things like this happen?

    I’d love to have CU’s data all the way back to 1992, if you know where that’s available drop me a line.

Comments are closed.