Archives par mot-clé : Sea level

Sea level rise: isostatic adjustment

by Judith Curry, June 23, 2018 in ClimateEtc.

Assuming that the uncertainty in GIA adjustments are ‘in the noise’ of global sea level rise may not be entirely justified.  The adjustments to the satellite data that emerged in the discussion between Morner and Nerem do not inspire confidence in the estimate of sea level rise from satellite data, and the low level of stated uncertainty strains credulity.


See also here

NSF study: ‘…current carbon dioxide levels are not enough to destabilize the land-based ice on Antarctica’

by Anthony Watts, June 15, 2018 in WUWT

We covered this yesterday, but today the official press release came out, so worth covering again. Via Eurekalert

Land-based portion of massive East Antarctic ice sheet retreated little during past eight million years

But increases in atmospheric carbon dioxide levels could affect stability and potential for sea level rise


Large parts of the massive East Antarctic Ice Sheet did not retreat significantly during a time when atmospheric carbon dioxide concentrations were similar to today’s levels, according to a team of researchers funded by the National Science Foundation (NSF). The finding could have significant implications for global sea level rise.


Sea Level Rise: Human Portion is Small

by Roy W. Spencer, Ph. D., May 25 2018 in GlobalWarming

There is a continuing debate over sea level rise, especially how much will occur in the future. The most annoying part of the news media reporting on the issue is that they imply sea level rise is all the fault of humans.

This is why the acceleration of sea level rise is what is usually debated, because sea level has been rising naturally, for at least 100 years before humans could be blamed. So, the two questions really are (1) Has sea level rise accelerated?, and (2) how much of the acceleration is due to humans?

Yesterday’s spat between Gavin Schmidt and Willis Eschenbach dealt with the question of whether sea level rise has accelerated or not. Gavin says it has. Willis says not, or at least not by a statistically significant amount. (…)

See also TOP 10 Climate Change Alarmist Myths Unearthed : #2 SEA LEVEL RISE

More Irrefutable Evidence of Small Island Stability In the Face of Climate Change

by Duvat et al.  2017, Global&Planetary Change in CO2Science

Writing as background for their study, Duvat et al. (2017) state that “it has commonly been considered that atoll reef islands would disappear under climate change, as a result of sea-level rise and induced accelerating shoreline erosion,” citing the works of Connell (2003), Dickinson (2009) and McAdam (2010). This perception is based on model predictions, which have been hyped all over the globe, especially among politicians and the media, some of whom demand reparations for small island States who they fear will be forced to abandon their islands within decades.

But how much faith should one place in such projections and concerns?

According to Duvat et al., not that much … (…)

Changes in the Rate of Sea Level Rise

by Willis Eschenbach, May 22, 2018 in WUWT

There’s been some discussion of the rate of sea level rise lately, so I thought I’d take a look at some underlying data.

I started with a 2016 paper by the modern master of failed serial doomcasting, James Hansen. It has the frightening title of Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2°C global warming could be dangerous… yikes! Be very afraid!

In Figure 29 of that paper, Hansen claims to show that sea level rise has been accelerating, from 0.6 mm/year from 1900 to 1930, to 1.4 mm/year from 1930 to 1992, and 2.6 mm/year from 1993 to 2015.


The Sea Is Rising, but Not Because of Climate Change

by Fred Singer, May 15, 2018 in TheWallStreetJournal

It is generally thought that sea-level rise accelerates mainly by thermal expansion of sea water, the so-called steric component. But by studying a very short time interval, it is possible to sidestep most of the complications, like “isostatic adjustment” of the shoreline (as continents rise after the overlying ice has melted) and “subsidence” of the shoreline (as ground water and minerals are extracted).

I chose to assess the sea-level trend from 1915-45, when a genuine, independently confirmed warming of approximately 0.5 degree Celsius occurred. I note particularly that sea-level rise is not affected by the warming; it continues at the same rate, 1.8 millimeters a year, according to a 1990 review by Andrew S. Trupin and John Wahr. I therefore conclude—contrary to the general wisdom—that the temperature of sea water has no direct effect on sea-level rise. That means neither does the atmospheric content of carbon dioxide.


10 new islands formed in the last 20 years

by Sidney Stevens, July 5, 2016 in

Yes, islands are disappearing — most recently the five Solomon Islands lost to rising sea levels. But don’t despair just yet. For every island that goes the way of the dodo bird, the Earth is busy creating new islands.

Some erupt into being through volcanic activity. Others grow from ocean sandbars. Still others reveal themselves after glaciers retreat. A few are only temporary, while some materialize and erode on a regular basis. However they’re birthed and however long they last, island-building is part of the amazing mystery of our living, breathing planet.

Here are 10 of Mother Nature’s newest islands formed in the past two decades (and one still in the embryonic stage).


Sea level rise acceleration (or not): Part VII U.S. coastal impacts

by Judith Curry, April 15, 2018 in Climate.Etc.

Global mean sea level (GMSL) has increased by about 8–9 inches since 1880, with about 3 inches occurring since 1993. As discussed in Part VI, scientists expect that GMSL will continue to rise well beyond the 21st century because of global warming that has already occurred and warming that is yet to occur.

The recent NOAA Report Global and Regional Sea Level Rise Scenarios for the United States has stated that even the relatively small increases in sea level over the last several decades have been associated greater storm impacts at many places along the U.S. coast. Further, the frequency of intermittent flooding associated with unusually high tides has increased rapidly in response to increases in local sea level, becoming a recurrent and disruptive problem.

70+ Papers: Holocene Sea Levels 2 Meters Higher – Today’s Sea Level Change Indistinguishable From Noise

by K. Richard, April 12, 2018 in NoTricksZone

More than 70 recent scientific publications show that there is absolutely nothing unusual about the magnitude and rapidity of today’s sea level changes. These academically peer-reviewed papers show that sea levels were on average 2 meters higher earlier in the Holocene than they are today.


Ocean Temps Falling Feb. 2018

by Ron Clutz, March, 2018 in ScienceMatters

The best context for understanding decadal temperature changes comes from the world’s sea surface temperatures (SST), for several reasons:

  • The ocean covers 71% of the globe and drives average temperatures;
  • SSTs have a constant water content, (unlike air temperatures), so give a better reading of heat content variations;
  • A major El Nino was the dominant climate feature in recent years.

HadSST is generally regarded as the best of the global SST data sets, and so the temperature story here comes from that source, the latest version being HadSST3.  More on what distinguishes HadSST3 from other SST products at the end.




1988 Congressional climate change hearing: claims of accelerating sea level rise – failed

by Larry Hamlin, March 14, 2018 in WUWT

In June 23, 1988 the Senate Committee on Energy and Natural Resources held a hearing addressing the Greenhouse Effect and Global Climate Change.

Among the presenters at this hearing was Dr. James Hansen, Director, NASA Goddard Institute for Space Studies who introduced his infamous and now debunked global surface temperature model results with future temperature projections under three different scenarios of CO2 emissions growth that grossly over exaggerated resulting projected global temperature increases.