The study by a consortium of scientists from the National Oceanography Centre, Southampton and research centres in Tübingen (Germany), Cambridge and New York, is published this week in the new journal Nature Geoscience.
The rate of future sea level rise is one of the crucial uncertainties in projections of future climate warming. During the last interglacial (124 to 119 thousand years ago), also known as the Eemian or Marine Isotope Stage 5e, the Earth's climate was warmer than it is today, due to a different configuration of the planet's orbit around the Sun.
It was also the most recent period in which sea levels reached around six metres (20 feet) above the present, due to melt-back of ice sheets on Greenland and Antarctica. The new results provide the first robust documentation of the rates at which sea level rose to these high positions.
Lead author, Professor Eelco Rohling of the University of Southampton's School of Ocean and Earth Science, based at the National Oceanography Centre, said: 'There is currently much debate about how fast future sea level rise might be. Several researchers have made strong theoretical cases that the rates of rise projected from models in the recent IPCC Fourth Assessment are too low. This is because the IPCC estimates mainly concern thermal expansion and surface ice melting, while not quantifying the impact of dynamic ice-sheet processes. Until now, there have been no data that sufficiently constrain the full rate of past sea level rises above the present level.
'We have exploited a new method for sea level reconstruction, which we have pioneered since 1998, to look at rates of rise during the last interglacial. At that time, Greenland was 3 to 5°C warmer than today, similar to the warming expected 50 to 100 years from now. Our analysis suggests that the accompanying rates of sea level rise due to ice volume loss on Greenland and Antarctica were very high indeed. The average rate of rise of 1.6 metres per century that we find is roughly twice as high as the maximum estimates in the IPCC Fourth Assessment report, and so offers the first potential constraint on the dynamic ice sheet component that was not included in the headline IPCC values.'
The researchers' findings offer a sound observational basis for recent suggestions about the potential for very high rates of sea-level rise in the near future, which may exceed one metre per century. Current ice-sheet models do not predict rates of change this large, but they do not include many of the dynamic processes already being observed. The new results highlight the need for further development of a better understanding of ice-sheet dynamics in a changing climate.
Sarah Watts | alfa
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The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
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22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy