The global sea level is rising at breakneck speed, it broke a 2800 year record in the 20th century, says an international team of scientists who were shocked at their findings. Global warming has caused sea level rises that could have even been reversed in the past 100 decades. During the 20th century, our seas rose by 5.5 inches (14 centimetres), which is a considerable increase, especially for vulnerable coastal areas at close to sea level. If we continue to rely on fossil fuels, our seas will rise even more this century. This latest study was published in the peer-reviewed journal Proceedings of the National Academy of Sciences by scientists from Germany, the UK, and the USA. (citation below). Half of all coastal flooding episodes since 1950 would probably not have occurred without the global warming of the 20th century. (Image: floodsax.co.uk) Sea level rise rate accelerating Lead author, Robert Kopp, an associate professor in the Department of Earth and Planetary Sciences at Rutgers, the State University of New Jersey, said: “The 20th-century rise was extraordinary in the context of the last three millennia – and the rise over the last two decades has been even faster.” Prof. Kopp, together with Jerry Mitrovica, a professor at Harvard University, Carling Hay and Eric Morrow, postdoctoral associates at Rutgers, developed a new statistical approach. Professor Kopp stated that no local record can measure global sea level. Every record measures sea level in a specific location. However, it can be affected by many factors that make it different from the global average. “The statistic challenge is to find the global signal. Our statistical approach makes it possible to achieve this. The Geological Society of America claims that our seas rise faster than predicted. With much of Florida sinking beneath the ocean, the map of America could change dramatically in the future. Image: geosociety.org. Small temperature fluctuations affect sea levels. Earth’s sea level fell about 3 inches (or 8 centimetres) between 1000 and 1400 AD. This occurred during a time when the global temperatures dropped by about 0.2degC (0.46degF). Scientists believe it’s striking that sea level changes can be attributed to such small temperature fluctuations. Compared to the late 19th century, average global temperatures are about 1degC (1.8degF) higher today. Imagine what a 1degC increase in global sea levels would do if a change of 0.2degC was made. If the data used to create statistical analyses is good, it will be useful. For this study, a team led by Professor Benjamin Horton, from Rutgers’ department of Marine and Coastal Services, and assistant Professor Andrew Kemp, from Tufts University, compiled a new database of geological sea-level indicators from coral atolls, marshes and archaeological sites spanning a period of 3,000 years. This database included records from 24 different places around the globe. The majority of records were compiled from fieldwork by Horton, Kemp and Roland Gehrels of the University of York, United Kingdom. Also included was data from 66 tide gauge records over the past 300 year. Professor Horton stated that future scenarios of rising sea levels depend on our ability to understand the climate change response. Accurate estimates of sea-level variability during the past 3,000 years provide a context for such projections.” Will London look like this one day? An international team of scientists has reported that sea-level rises and variability caused by climate change are likely to continue for many thousand years. This is regardless of how much we do try to reduce our greenhouse gas emissions. (Image: london-futures.com) Sea level reconstruction today extremely detailed Prof. Kemp said: “As geologists, we can reconstruct how sea level changed at a particular site, and progress in the last 10 years has allowed us to do so with ever more detail and resolution.” “Gathering together and standardizing these reconstructions gave us a chance to look at what they had in common and where they differed, both of which can tell us about the causes of past, present and future sea-level change.” Co-authors, Stefan Rahmstorf and Klaus Bittermann, who work at the Potsdam Institute for Climate Impact Research in Germany, calculated how temperatures are linked to the rate of sea-level change by using the study’s global sea-level reconstruction. Without global warming sea-level might have declined Based on this temperature-sea level relationship, the scientists found that without global warming, the global sea level in the 20th century would have changed between a decrease of 1.2 inches (3 centimetres) and a rise of 2.8 inches (7 centimetres). A companion report found that without the climate change-induced component of sea-level rise, over half of the 8,000 coastal nuisance floods detected at studied US tide gauge sites since 1950 would have been avoided. Researchers also concluded that global sea levels will likely increase by between 1.7 and 4.3 feet (0. 51 up to 1. 31 meters) if fossil fuels are continued to be used. We could lower the rise by phasing out fossil fuels as soon as possible, to between 0.8- 2 feet (or more). 24 up to 0.6 meters In an Abstract in the journal, the authors wrote: “The 20th century rise was extremely likely faster than during any of the 27 previous centuries. Semiempirical modeling indicates that, without global warming, GSL in the 20th century very likely would have risen by between -3 cm and +7 cm, rather than the ~14 cm observed.” In a report published this month, the authors predict that by 2116 many of us will be living in underwater towns with large skyscrapers. (Image: samsung.com/uk/pdf/smartthings) Underwater cities may be common by 2116 A report, commissioned by Samsung-owned company – SmartThings – predicted that architects, civil engineers and town planners will soon start looking at how we could build cities under the sea. These cities will have huge skyscrapers as well as 3D-printed houses. Instead of driving cars, people would be able to fly their own drones. They could transport you home, or even your vacation destination, using these drones. According to the SmartThings Future Living Report, if sea levels continue to rise, then humans will be living on less land. We will not be able to stop the consequences of global warming. 71% of the planet’s total surface is water. Perhaps we could live under the ocean if this percentage increases. Citation: “Temperature driven global sea-level variability during the Common Era” Robert E. Koppa and Andrew C. Kemp. Also, Klaus Bittermann and Benjamin P. Horton. W. Roland Gehrels. Carling C. Hay. Jerry X. Mitrovica. Eric D. Morrow. Stefan Rahmstorf. Proceedings of the National Academy of Sciences. 22 February 2016. DOI: 10.1073/pnas.1517056113. Video – 10 countries most threatened by sea level rise If sea levels rise by 6 metres in the not-too-distant future, which this video says is highly likely as the ice in Greenland and Antarctica melts, ten countries will be particularly badly affected. Experts say the Netherlands, with 60% its population living in the 6-metre zone of sea level rise would be the worst affected. Soon, Egypt’s
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