Claimed 3.2 Millimeters Per Year Sea Level Rise Seriously Challenged By Recently Published Scientific Papers!

Challenged: 3.2 mm/year sea level rise since 1993

By guest author Kenneth Richard

Source data studies indicate recent only 0.8 – 1.6 mm/year sea level rise.

According to the IPCC (2013), sea levels rose at a rate of 1.7 mm/year (6.7 inches per century) for the 1901 to 2010 period, but 3.2 mm/year (12.6 inches per century) during the 18-year period between 1993 to 2010, a rate similar to that obtained from 1920 to 1950.

If sea levels truly were rising at rates of 3.2 mm/year between 1993 and 2010 as the IPCC (2013) claims with high confidence, then the thermal and ablation sources for that sea level rise should at least somewhat closely add up to 3.2 mm/year for the same period.  But if the sources for the sea level rise as determined by published studies only reach between 0.8 and 1.6 mm/year when added together – a quarter to half of the 3.2 mm/year claimed – then that suggests that there is something seriously questionable about the 3.2 mm/year sea level rise estimates for 1993 to 2010 obtained by satellite altimetry.

What follows is an abridged list of recent papers showing that sea level rise estimations claimed by the IPCC are likely highly exaggerated.

“It is very likely that the global mean rate was 1.7 mm yr–1 between 1901 and 2010 for a total sea level rise of 0.19 m. Between 1993 and 2010, the rate was very likely higher at 3.2 mm yr–1; similarly high rates likely occurred between 1920 and 1950.”

Problematically, in recent decades the source contribution estimates for recent decades from published studies add up to half (or less) of this claimed rate.

According to recent estimates, the contribution to sea level rise from thermal expansion was 0.64 mm/yr (2.5 inches per century) for the period between 2005-2013 (Llovel et al., 2014, see below). The contribution from the Greenland (GIS) and Antarctic (AIS) ice sheets was 0.59 mm/yr (2.3 inches per century) for the 1992-2011 period (Shepherd et al., 2012).  The contribution from global glaciers and ice caps that are not the GIS or AIS was 0.41 mm/yr (1.6 inches per century) for 2003-2010 (Jacob et al., 2012).

Llovel et al., 2014

Over the entire water column, independent estimates of ocean warming yield a contribution of 0.77 ± 0.28 mm yr−1 in sea-level rise … the deep ocean (below 2,000 m) contributes −0.13 ± 0.72 mm yr−1 to global sea-level rise [0.64 mm/yr total].

Shepherd et al., 2012

Since 1992, the polar ice sheets [Antarctica and Greenland] have contributed, on average, 0.59 ± 0.20 millimeter year−1 to the rate of global sea-level rise.

Jacob et al., 2012

Here we show that GICs [glaciers and ice caps], excluding the Greenland and Antarctic peripheral GICs, lost mass at a rate of 148 ± 30 Gt yr−1 from January 2003 to December 2010, contributing 0.41 ± 0.08 mm yr−1 to sea level rise.

These sources add up to about 1.6 mm/year, which is the equivalent of a little over 6 inches per century.  Interestingly, this is the same or slightly less than the rate for the entire 1901 to 2010 period (1.7 mm/year, IPCC), meaning that sea level rise has not accelerated in recent decades according to the summation of source estimates.

Another recent estimate of the sea level contribution from the Antarctic ice sheet (Zwally et al., 2015, see below) for 1992-2008 has East Antarctica ice mass gains exceeding the losses from West Antarctica, indicating a net gain in ice mass for the continent as a whole and a negative sea level contribution of -0.23 mm/year (-0.9 of an inch per century) for 2003 to 2008.

Mass changes of the Antarctic ice sheet impact sea-level rise as climate changes, but recent rates have been uncertain. Ice, Cloud and land Elevation Satellite (ICESat) data (2003–08) show mass gains from snow accumulation exceeded discharge losses by 82 ± 25 Gt a–1, reducing global sea-level rise by 0.23 mm a–1. European Remote-sensing Satellite (ERS) data (1992–2001) give a similar gain of 112 ± 61 Gt a–1.

“The good news is that Antarctica is not currently contributing to sea level rise, but is taking 0.23 millimeters per year away,” Zwally said.

Along with the sea level decline equivalent of -0.23 mm/year for 2003-2008 due to ice gains of +82 Gt per year between 2003 and 2008, we can compute the sea level loss equivalent for 1992-2001 as -0.31 mm/yr, as 1992-2001 had a higher rate of mass gain (+112 Gt/year) for the Antarctic ice sheet as a whole.  Averaged together, the Zwally et al. (2015) study indicates that Antarctica took away -0.28 mm/yr (-1.1 inches) from sea levels over 1992-2008.

Using this -0.28 mm/year estimate for Antarctica’s ice melt contribution instead of the Shepherd et al. (2012) estimate of 0.19 mm/year (0.7 of an inch per century), but yet continuing to use the Shepherd et al. (2012) estimate for Greenland’s ice sheet contribution (0.4 mm/year) reduces the polar ice sheet contribution from 0.59 mm/year to 0.12 mm/year, which is a sea level contribution of half an inch (0.5) per century from both polar ice sheets combined.

This change of -0.47 mm/year effectively reduces the 1.6 mm/year source estimate from above to between 1.1 and 1.2 mm/year, a little over 4 inches per century.

The template for the above source analysis of sea level rise contributions was provided in the journal Science  by Cabanes et al., 2001.  Here is their summary for the last few decades of the 20th century.

The third assessment report of the Intergovernmental Panel on Climate Change (IPCC) estimates the various factors that have contributed to the 20th century sea level rise. The largest contribution (0.7 mm/year sea level rise) arises from thermal expansion due to warming of the oceans that mainly occurred since the 1950s. Melting of continental glaciers produces 0.2 to 0.4 mm/year sea level rise. Estimated Greenland and Antarctica mass imbalance (accounting for a long-term readjustment since Last Glacial Maximum plus a climate-related response) contributes –0.2 to 0.6 mm/year. The least certain contribution is the change in terrestrial water storage that results partly from human activities, which is in the range of –1.1 to + 0.4 mm/year with a median value of −0.35 mm/year (i.e., corresponding to sea level drop). The sum of these contributions ranges from −0.8 to 2.2 mm/year, with a median value of 0.7 mm/year.

Notice that in this analysis, “terrestrial water storage” is included in the contribution budget, and this amounted to -0.35 mm/year (with a range of “–1.1 to + 0.4 mm/year”)  for the late 20th century.  A more recent estimate is apparently not available, but it is likely a fair assumption that these parameters for terrestrial water storage haven’t changed significantly during the first decade of the 21 century compared to the last decades of the 20th.  Therefore, it would be reasonable to include this value among the source contributions to recent sea level rise.  This would effectively reduce the 1.1 to 1.2 mm/year rate described above (using Zwally et al., 2015) to about 0.8 mm/year, which is very similar to the 0.7 mm/year calculated for the last decades of the 20th century by Cabanes et al., 2001.  A rate of 0.8 mm/year is equivalent to about 3 inches per century.


22 responses to “Claimed 3.2 Millimeters Per Year Sea Level Rise Seriously Challenged By Recently Published Scientific Papers!”

  1. yonason

    Sea level is rising the same way temperatures are rising.

    Of course it’s rising, but only when the data is properly “adjusted.”

    Lots more here:

    1. Tom

      You got that right – tons of info about the fraud – and it can be shown from their own data. Time and time again it is independent skeptic bloggers or non-government funded scientists that find the rookie flaws, which are obvious tampering (at best confirmation bias, but I think we are beyond that)… Not to mention, most of the sea ice is UNDER WATER – when you put an ice cube in a glass of water, then mark the level, then check after it melts, their is no change in the level of the water…but they don’t mention this – not that I think their is ANY significant melting, none that has not been going on, even in natural cooling cycles…

      1. yonason

        Yup. And if you add crushed ice to a bucket of water, so it’s just covering the surface, then use a paddle to bush aside some ice, you’ll get an ice free surface. That’s just like the wind blowing the ice aside in the Arctic. Warmists pretend it’s due to melting, when there is no less total ice.

        With their lies, they are doing irreparable harm to the image of science, from which it may take a long time to recover.

      2. Brian H

        there is

  2. tom0mason

    I note that the much advertised accelerating sea-level rise has so gripped seafaring nations and port authorities worldwide that PANIC building of sea defenses has begun in earnest everywhere
    — or Not as the case truly is —
    NO it has not as real port authorities witness the true rate of sea-level rise everyday. Only a few office-bound port authority third-rate bureaucrats are beating that drum while others are dumb enough to approve funding of such a boondoggle with taxpayer’s money.

    1. yonason

      The headline reads:

      Land lubbers warn unwary seafarers “water rapidly getting wetter!”

      Front page material, or the plot of a Goons Show?

      1. yonason

        What I mean by a Goons Show plot

        E.g., from “The Fireball Of Milton Street”

        Dear Mr. Seagoon, Henry said the sun’s on fire.

        On fire? [laughs to himself] You were always one for a joke!

        No I’m not, look I took this photo of the sun’s coroner and it’s smoking.

        Hmm, heavens above and saints protect us! He’s right! The sun’s on fire! We must tell the villagers at once. [Panic] The sun’s on fire! The sun’s on fire!!!”

        Fast forward to today, and the world is full of goons, and they are all either politicians, junk-scientists or useful-idiots shouting, “The Earth’s On Fire.”

  3. Michael Snow

    And the propaganda keeps coming. Yesterday, I heard on my local radio the CBS News which had a scare story that sea level rise may have been UNDER estimated, and they where touting a 6 foot rise by the end of the century.

    1. yonason

      Prof. Nils-Axel Mörner goes into details they want to keep us ignorant of:
      He shows us what either utter fools they are, or what pathological liars. (probably both, IMO)

      Interview of him that may be worth listening to:

    2. John F. Hultquist
    3. Colorado Wellington

      Pikers. I’ll see their 6 feet and raise them 54 feet. They are not man enough to predict a real sea upwelling.

      1. yonason

        Arrr, Matey, we better keep an eye on this one!

  4. Graeme No.3

    Hysteria by the believers as they see Trump rubbishing their theory and not being struck down by a thunderbolt. Worse other politicians are doing the same, and they are desperately trying to drown them out.

    The believers are pretty small in numbers. Even if you feel that half the population of the USA and in Europe believe them, the number of people in the World who don’t believe or care about “Climate Change etc” is getting close to 97%. In the whole of Asia, Africa, and South America the only ones supporting the conjecture are those trying to get some of the flowing money. Let doubt creep in, the flow will slow and few will want to remain on the sinking ship.

    1. DirkH

      “Hysteria by the believers as they see Trump rubbishing their theory and not being struck down by a thunderbolt.”

      Just give it time. Might not exactly be a THUNDERBOLT though.

  5. tom0mason

    But NASA has just issue (Feb 2016)their excuse for no sea-level rise, and they assure everyone that the water has found its way into the underground aquifers. This miraculous happening is rationalized by refiddling the latest data from a pair of NASA satellites launched in 2002—known as the Gravity Recovery and Climate Experiment (GRACE).

    Satellite measurements over the past decade show for the first time that the Earth’s continents have soaked up and stored an extra 3.2 trillion tons of water in soils, lakes and underground aquifers, the experts said in a study in the journal Science.

    This has temporarily slowed the rate of sea level rise by about 20 percent, it said.

    “We always assumed that people’s increased reliance on groundwater for irrigation and consumption was resulting in a net transfer of water from the land to the ocean,” said lead author J.T. Reager of NASA’s Jet Propulsion Laboratory.

    “What we didn’t realize until now is that over the past decade, changes in the global water cycle more than offset the losses that occurred from groundwater pumping, causing the land to act like a sponge—at least temporarily.”

  6. Ed Caryl

    Then add in the water from draining land-locked lakes, and pumping out aquifers, about 0.77 mm/year.

  7. Stuart L

    Your own tide gauge record at Wismar is one of the longest consistent record. from 1850 (when CO2 was low) till now (escalated CO2 levels)the rate of rise is linear at 1.41mm per year, clearly CO2 has zero effect on sea levels

    1. Lasse

      You can also see the lack of acceleration and a minor periodical cycle in Wismar:

    2. AndyG55

      Australia is a net carbon sink, and Fort Denison in Sydney Harbour has a sea level rise rate of 0.65mm/year.

      Sea level rise in not Australia’s fault. 😉

  8. Mark

    The IPCC have known since 2007 that the Antarctic was reducing sea level, it’s in their report from that year.

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