New, Vast Body Of Literature Shows Rates Of Glacier Retreat, Sea Level Change, Now Significantly LOWER!

By guest author Kenneth Richard

According to recently published scientific papers, the current sea level highstand, as well as the rate of glacier retreat and sea level change, are now significantly lower than they have been for much of the last 10,000 years — back when CO2 concentrations were stable and considerably lower (at about 265 ppm).

Ocean Atlantic Tiago Floreze

A flurry of new papers show today’s sea level rise is slower than in the Holocene past. Photo Tiago Floreze, CC BY-SA 3.0.

The most recent IPCC report (2013) indicates that sea levels have been rising at a rate of 1.7 mm/year, or 6.7 inches per century, since 1901 (through 2010).  This rate occurred synchronously with an approx. 100 ppm increase in atmospheric CO2 levels.

In contrast, scientists Hodgson et al., 2016 have determined that sea levels rose at rates of 1.2 to 4.8 meters per century (47 to 188 inches, or about 4 to 16 feet per century) between about 10,500 and 9,500 years ago near East Antarctica.  This sea level rate change occurred while CO2 levels were stable to modestly declining *.

In the paper: Rapid early Holocene sea-level rise in Prydz Bay, East Antarctica, the authors write:

Prydz Bay is one of the largest embayments on the East Antarctic coast and it is the discharge point for approximately 16% of the East Antarctic Ice Sheet. […] The field data show rapid increases in rates of relative sea level rise of 12–48 mm/yr between 10,473 (or 9678) and 9411 cal yr BP [calendar years before present].”

The recently published scientific literature also indicates that not only was the historical rate of sea level rise significantly higher than it has been since the 20th century began, glaciers and ice sheets continued to rapidly retreat during the late Holocene, or within the last few thousand years.  During the Medieval Warm Period, for example, scientists Guglielmin et al., 2016 determined that glacier retreat rates in the Western Antarctic Peninsula were as high or higher than they have been in recent decades.

In the publication here, the authors write:

Here, we present evidence for glacial retreat corresponding to the MWP [Medieval Warm Period] and a subsequent LIA [Little Ice Age] advance at Rothera Point (67°34′S; 68°07′W) in Marguerite Bay, western Antarctic Peninsula. … Based on new radiocarbon dates, during the MWP, the rate of glacier retreat was 1.6 m yr−1, which is comparable with recently observed rates (~0.6 m per year between 1993 and 2011 and 1.4 m per year between 2005 and 2011).”

Prior to the Medieval Warm Period, scientists Yokoyama et al., 2016 indicate that “the world’s largest ice shelf” collapsed due to a warming ocean and atmosphere, with ice shelf retreat rates of 100 km within a thousand years.

In the publication Widespread collapse of the Ross Ice Shelf during the late Holocene, the authors write:

The Ross Sea is a major drainage basin for the Antarctic Ice Sheet and contains the world’s largest ice shelf. … Breakup initiated around 5 ka [5,000 years ago], with the ice shelf reaching its current configuration ∼1.5 ka [1,500 years ago]. In the eastern Ross Sea, the ice shelf retreated up to 100 km in about a thousand years. … [I]ce-shelf breakup resulted from combined atmospheric warming and warm ocean currents impinging onto the continental shelf.”

According to other scientists Bradley et al., 2016, the melt water from the Antarctic ice sheet continued to contribute up to 5.8 meters of sea level rise equivalent until about 1,000 years ago.

In another recent paper here the authors found:

…a slowdown in melting at ∼7 kyr BP associated with the final deglaciation of the Laurentide Ice Sheet, followed by a continued rise in ESL [Holocene ice volume equivalent sea level] until ∼1 kyr BP of 5.8 m associated with melting from the Antarctic Ice Sheet.”

Due apparently to the high glacier-melt rates and warmer ocean temperatures (Rosenthal et al. [2013]** indicate that 0-700 m Pacific Ocean temperatures were still ~0.65° C warmer than present ~1,000 years ago), recently published scientific papers document that sea levels stood from 1 to 4 meters higher than now as recently as a few thousand years ago (see citations below).

The big mystery

These scientific conclusions beg the question: If CO2 is a primary determinant of changes in sea level, why is it that sea level highstands (and sea level rise and glacier melt rates) were significantly greater when CO2 concentrations were stable and low than they have been in recent decades?

Publications to read:

www.sciencedirect.com/science/article/pii/S0048969715311700

The configuration suggests surface inundation of the upper sediments by marine water during the mid-Holocene (c. 2–8 kyr BP) [2,000-8,000 years before present], when sea level was 1–2 m above today’s level.

—–

www.sciencedirect.com/science/article/pii/S0033589415000642

….a [sea level] highstand at ~ 5000–3500 cal yr BP. The berms [raised land embankments] are presently at ~ + 6 m above [present] sea level, 2–3 m above the beach ridges. Human settlements were common on the ridge crests before and after the highstand. Regression to present-day sea level commenced after the highstand, which is when the sabkha began forming.”

—–

www.sciencedirect.com/science/article/pii/S0031018213004689

Highlights

  • We present a sea level change curve for mid Holocene in Uruguay.
  • Sea level reached 4 m amsl[above mean sea level today]between 6000 and 5500 yr BP [years before present].
  • A rapid sea level fall to about 1 m amsl was inferred for 4700-4300 yr BP.
  • A further sea level increase to about 3 m amsl [above mean sea level today]was inferred after 4300 yr BP

—-

* Epica Dome C ice core data [Antarctica] indicate that CO2 levels declined slightly from 268 ppm 10,458 years ago to 264 ppm 9,399 years ago.

** Rosenthal et al., 2013

http://science.sciencemag.org/content/342/6158/617.abstract

We show that water masses linked to North Pacific and Antarctic intermediate waters were warmer by 2.1 ± 0.4°C and 1.5 ± 0.4°C, respectively, during the middle Holocene Thermal Maximum than over the past century. Both water masses were ~0.9°C warmer during the Medieval Warm period than during the Little Ice Age and ~0.65° warmer than in recent decades.”

9 responses to “New, Vast Body Of Literature Shows Rates Of Glacier Retreat, Sea Level Change, Now Significantly LOWER!”

  1. John F. Hultquist

    Nice summary, thanks.

    Here is a link to the (commanly seen) post-glacial sea level rise:
    https://en.wikipedia.org/wiki/File:Post-Glacial_Sea_Level.png
    Its mate on that site has info from 1880 to 2014. I don’t know about the accuracy of either.

    ~~~~~
    If CO2 is a primary determinant …

    Many folks claim carbon dioxide concentration has an exponentially decreasing effect after a certain point and that at “265 ppm” that point has been seen long ago. Now at about 400 ppm, the concentration would have to get to 800 for the, assumed, doubling of the temperature rise from 200 to 400.
    In so far as a rise to 800 ppm seems unlikely from human-driven emissions the great global warming scare should be called off.
    We have been informed elsewhere that the UN and others just want to redistribute wealth from the countries that produce it, to those that can’t. Global warming or climate change is the excuse to do this. Global cooling would work too. If the climate never changes (that’s a funny story) the redistributionists will have to have another issue. They will.

    1. DirkH

      Warming leads to more CO2 outgassing at the ocean surface and to rising CO2 levels. And let’s just assume that CO2 *DOES* have a warming effect. So we have a feedback loop. The logarithmic nature of the (alleged) CO2 greenhouse effect though leads to an ever diminishing Q-factor of the positive feedback as CO2 levels rise.

      And that explains why there has never been a thermal runaway in the history of the planet (which would also be a thermodynamical miracle).

  2. Whirled Publishing

    CO2 is not the cause of the rapid glacial melt – or global warming.

    the heat from magma uplift, sea floor volcanic eruptions and other volcanic activity –

    the ocean waters are being heated by sea floor volcanic eruptions –

    the unusually warm ocean water is melting the ice sheets from below.

    Hot spots on the anomaly maps show where this heat is –

    some of the heat is coming from volcanic activity beneath the Antarctic ice sheet, beneath the Greenland ice sheet, beneath Baffin Bay, along the New England coast, on the sea floor of the Sea of Cortex, in the South Pacific, the equatorial Pacific, north of Europe, etc.

    The heat in the oceans is releasing the methane which rises into the atmosphere and traps the heat from the volcanic eruptions, wildfires, automotive exhaust, etc.

    The warm ocean waters are rapidly evaporating, being carried wind currents to nearby low pressure systems where record rainfall is destroying homes, roads, bridges, causing landslides, sinkholes, etc.

    The warm ocean waters is also carving river tunnels into the ice shelves – below the surface of the ocean

    few people are aware of the devastation that will soon be upon us –

    based on the trajectory of thousands of independent sources of climate data from around the world, the climate forecast includes a domino effect of killer quakes, catastrophic tsunami waves, destruction of nuclear reactors around the world, lethal radiation poisoning, inundations, hurricane force winds, devastation by tornadoes, homelessness, a worldwide famine, horrific violence, death by lightning strikes, disease, starvation, etc.

  3. Whirled Publishing

    Sea Surface Temperature Anomaly map –

    the Arctic Oceans relatively shallow waters results in the sea floor volcanoes heating it up faster than any other place on the Earth:

    http://polar.ncep.noaa.gov/sst/ophi/color_newdisp_anomaly_global_lat_lon_ophi0.png

  4. handjive

    Around 20,000 years ago, at the coldest time of the last ice age, the sea level was about 120 metres below its present level.

    But as temperatures rose, huge masses of ice started to melt and pour waters into the world’s oceans. During the next 13,000 years, sea levels gradually rose to reach their current levels.

    In regions of Australia where the coastal land had a low topography, even a small rise in sea level would have claimed large chunks of land relatively quickly.

    “People must have been aware that every year the sea was on the rise,” Reid says. “And they must have had stories from their fathers and grandfathers, and great-grandfathers, that the sea used to be out even further.”

    Some of these stories are pragmatic descriptions of a time when sea levels were lower, such as memories of the loss of kangaroo hunting grounds around Port Phillip Bay near Melbourne.
    http://www.bbc.com/earth/story/20160118-the-atlantis-style-myths-of-sunken-lands-that-are-really-true

    Aboriginal Memories of Inundation of the Australian Coast Dating from More than 7000 Years Ago

    Stories are presented from 21 locations from every part of this coastline.
    In most instances it is plausible to assume that these stories refer to events that occurred more than about 7000 years ago, the approximate time at which the sea level reached its present level around Australia.
    http://www.tandfonline.com/doi/full/10.1080/00049182.2015.1077539

    More Australia:
    Victoria’s iconic Twelve Apostles may have to rethink its name after the discovery of five extra limestone columns hidden deep beneath the ocean.
    The sea stacks, thought to be up to 60,000 years old, were discovered during sonar mapping of Victoria’s southern coast.

    University of Melbourne PhD candidate Rhiannon Bezore, who made the initial discovery in the sonar data, said sea level changes had played a critical role in the structure’s survival.

    “The main factor is that through the past geological changes they’ve been through, the sea level rise has occurred at such a fast pace,” she said.

    “Because of that, they’ve actually been submerged before erosional processes could come and knock them over.”

    http://www.abc.net.au/news/2016-03-10/hidden-apostles-found-underwater-off-great-ocean-road/7234906

  5. Kenneth Richard

    http://www.sciencedirect.com/science/article/pii/S1040618215002165
    The Holocene-high-stand (HHS) inferred from oyster fossils (Saccostrea echinata and Saccostrea malaboensis) is 2.7 m [above present sea level] at ca. 3500 years ago, after which sea level gradually fell to present level.

    http://onlinelibrary.wiley.com/doi/10.1002/esp.3663/abstract
    The foredunes overlie upper beach deposits located up to >2 m above the present upper beach level and provide evidence for a higher mid-Holocene RSL [relative sea level].

    http://www.vims.edu/research/units/labgroups/coastal_geology/_Publication_PDFs/Brazil%20Coastal%20Seds%20Paper%202015.pdf
    Introduction: In southern Brazil, falling RSL [relative sea level] following a 2–4 m [above present sea level] highstand at 5 to 6 ka [5,000 to 6,000 years ago] forced coastal progradation.

  6. Denis Ables

    co2 increase wasn’t synchronously increasing with global warming either.
    Our current warming (such as it is) BEGAN, not in the mid 1800s (cherry-picked start date, coinciding with our industrial revolution) but at the bottom of the earlier Little Ice Age, which was in the middle 1600s.

    That’s two centuries BEFORE co2 began increasing. Not only that, even the rabid alarmists recognize that co2 (increasing at about 2 ppmv per year) would have had to increase for another century before there would be any chance of having an impact on the measurable temperature increase. That’s 300 YEARS of natural warming BEFORE co2 could have possibly had any impact.

    That brings us to about 1950. But, there was a mild cooling from the 40s to the 70s, which pushes the natural warmer above 300 years. Then there is the fact that both weather satellites show a trend of NO additional warming beginning in 1998 and going at least 18 years – into 2015.

    The only reason that trend may now temporarily change is because an El Nino hit around mid year 2015. NASA has (on the one hand) admitted that this is a really big El Nino, perhaps bigger than the previous one 1997-1998, and that it is a natural phenomenon. But the political hacks running NASA and NOAA (and obviously lipsynching Obama) are still trying to blame the El Nino on ….. human activity.

    They’re right, but they failed to admit that it is THEIR fraudulent activity !

  7. H. D. Hoese

    This has been reported from the Gulf of Mexico based on marine caused processes leaving features above current sea level.

    Morton, R.A., J. G. Paine and M. D. Blum. 2000. Resposes of stable bay margin and barrier-island systems to holocene sea-level highstands, western Gulf of Mexico. Journal of Sedimentary Petrology. 70(3):478-490.

  8. Weekly Climate and Energy News Roundup #220 | Watts Up With That?