(https://www.washingtonpost.com/energy-environment/2018/09/20/antarctica-warming-could-fuel-disastrous-sea-level-rise-study-finds/?noredirect=on&utm_term=.b354d28a1e03)
both geological data5,6,7 and ice sheet models3,8 indicate that marine-based sectors of the East Antarctic Ice Sheet were unstable during Pliocene warm intervals, the ice sheet dynamics during late Pleistocene interglacial intervals are highly uncertain3,9,10. Here we provide evidence from marine sedimentological and geochemical records for ice margin retreat or thinning in the vicinity of the Wilkes Subglacial Basin of East Antarctica during warm late Pleistocene interglacial intervals. (https://www.nature.com/articles/s41586-018-0501-8)
The Antarctic is gaining 2,000 gigatonnes per year of ice. And, the researchers have convoluted the data show it losing a net 70 to 190 gigatonnes. All of this "loss" is modeled not measured. Where measurement takes place, the Antarctic is gaining ice. (https://www.washingtonpost.com/energy-environment/2018/09/20/antarctica-warming-could-fuel-disastrous-sea-level-rise-study-finds/?noredirect=on&utm_term=.b354d28a1e03)
Scientists say the pace of sea level rise has nearly tripled since 1990 (https://www.washingtonpost.com/news/energy-environment/wp/2017/05/22/scientists-say-the-rate-of-sea-level-rise-has-nearly-tripled-since-1990/?utm_term=.d1186aa889ef)
“We have a much stronger acceleration in sea level rise than formerly thought,” said Sönke Dangendorf, a researcher with the University of Siegen in Germany who led the study along with scientists at institutions in Spain, France, Norway and the Netherlands..... Studying the changing rate of sea level rise is complicated by the fact that scientists only have a precise satellite record of its rate going back to the early 1990s. Before that, the records rely on tide gauges spread around the world in various locations.
But sea level rise varies widely in different places, due to the rising and sinking of land, large-scale gravitational effects on the waters of the globe and other local factors. So scientists have struggled to piece together a longer record that merges together what we know from satellites with these older sources of information. .... Robert Kopp, a Rutgers University sea level researcher who has also published research showing a sharp acceleration of sea level rise, called the new study a “nice analysis” in an email to The Washington Post.
“Their final estimate of 20th century (particularly pre-1990) global mean sea level rise is in good agreement with the results of the two different analyses presented by [our] 2015 paper, and less than those of most other reconstructions,” Kopp said.... “Sea levels will continue to rise over the coming century, no matter whether we will adapt or not, but I think we can limit at least a part of the sea level rise. It will further accelerate, but how much is related to how we act as humans,” Dangendorf said.(https://www.washingtonpost.com/news/energy-environment/wp/2017/05/22/scientists-say-the-rate-of-sea-level-rise-has-nearly-tripled-since-1990/?utm_term=.d1186aa889ef)
Estimates of global mean sea level (GMSL) before the advent of satellite altimetry vary widely, mainly because of the uneven coverage and limited temporal sampling of tide gauge records, which track local sea level rather than the global mean. Here we introduce an approach that combines recent advances in solid Earth and geoid corrections for individual tide gauges with improved knowledge about their geographical representation of ocean internal variability. Our assessment yields smaller trends before 1990 than previously reported, leading to a larger overall acceleration; identifies three major explanations for differences with previous estimates; and reconciles observational GMSL estimates with the sum of individually modeled contributions from the Coupled Model Intercomparison Project 5 database for the entire 20th century.... The rate at which global mean sea level (GMSL) rose during the 20th century is uncertain, with little consensus between various reconstructions that indicate rates of rise ranging from 1.3 to 2 mm⋅y−1. Here we present a 20th-century GMSL reconstruction computed using an area-weighting technique for averaging tide gauge records that both incorporates up-to-date observations of vertical land motion (VLM) and corrections for local geoid changes resulting from ice melting and terrestrial freshwater storage and allows for the identification of possible differences compared with earlier attempts. (https://www.pnas.org/content/114/23/5946)
Climatologist counters climate-disaster predictions with sea-level report
For years, climate prognosticators have warned that human-caused global warming is fueling catastrophic sea-level rise, but now climatologist Judith Curry is rocking their boat.In her latest paper, Ms. Curry found that the current rising sea levels are not abnormal, nor can they be pinned on human-caused climate change, arguing that the oceans have been on a “slow creep” for the last 150 years — before the post-1950 climb in carbon-dioxide emissions.
“There are numerous reasons to think that projections of 21st-century sea level rise from human-caused global warming are too high, and some of the worst-case scenarios strain credulity,” the 80-page report found.
Her Nov. 25 report, “Sea Level and Climate Change,” which has been submitted for publication, also found that sea levels were actually higher in some regions during the Holocene Climate Optimum — about 5,000 to 7,000 years ago. (https://www.washingtontimes.com/news/2018/dec/27/judith-curry-sea-level-study-disputes-climate-disa/)
Judith A. Curry is the former chairman (2002 - 2014) and former professor at the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology. Judith Curry resigned from her position at Georgia Tech on January 1, 2017, citing the “craziness” of climate science, (https://www.desmogblog.com/judith-curry)
Maar dat is wellicht Amerikaans gezever, wat zouden onze Nederlandse wetenschappers zeggen?
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