New model predicts rising sea level by 2500
Global warming is playing havoc with the planet and some of the consequences we face because of this change are economic troubles, social disturbances and forced migrations. But another problem is the rising sea levels we and our future generations will encounter. Now scientists in China, Denmark, Finland, Sweden and the United Kingdom have developed a climate model to give us a long-term outlook for rising sea levels in relation to the emission of greenhouse gases and pollution. The model is presented in the journal Global and Planetary Change. The projections provided by scientists at the Centre for Ice and Climate, Niels Bohr Institute in Denmark and colleagues go as far forward as 500 years. 'Based on the current situation we have projected changes in sea level 500 years into the future,' says Aslak Grinsted from the Centre for Ice and Climate, the Niels Bohr Institute at the University of Copenhagen in Denmark. 'We are not looking at what is happening with the climate, but are focusing exclusively on sea levels.' The developed model is based on the outcome of greenhouse gas and aerosol emissions, as well as atmospheric pollution, according to the researchers. The team adjusted the model backwards to the actual measurements, which were used to determine the outlook of rising sea levels. Their outlook is based on four scenarios: two realistic, one pessimistic and one optimistic. The realistic scenarios show - on the assumption that emissions and pollution levels stabilise - that the sea level will rise by around 75 centimetres by the year 2100 and by 2 metres by the year 2500. The pessimistic scenario shows increasing emissions, making sea levels rise 1.1 m by the year 2100 and 5.5 m by the year 2500. The optimistic scenario - which depends on the most dramatic climate change goals, and requires sophisticated technology and global collaboration to ensure that greenhouse gas emissions and atmospheric pollution levels are squashed - shows that the sea level will rise by 60 cm by the year 2100 and by 1.8 m by the year 2500. 'In the 20th century sea has risen by an average of 2 millimetres per year, but it is accelerating and over the last decades the rise in sea level has gone approximately 70% faster,' says Dr Grinsted, one of the authors of the study. 'Even if we stabilise the concentrations in the atmosphere and stop emitting greenhouse gases into the atmosphere, we can see that the rise in sea level will continue to accelerate for several centuries because of the sea and ice caps long reaction time. So it would be 2-400 years before we returned to the 20th century level of a 2 mm rise per year.' Although nothing is written in stone with respect to these long-term calculations, the sea will continue to rise in the coming centuries, according to the researchers. Experts from the College of Global Change and Earth System Science, Beijing Normal University in China, the Arctic Centre at the University of Lapland in Finland, Uppsala University in Sweden and the National Oceanography Centre in the United Kingdom contributed to this study.For more information, please visit:University of Copenhagen:http://www.ku.dk/english/Global and Planetary Change:http://www.elsevier.com/wps/find/journaldescription.cws_home/503335/description
Countries
China, Denmark, United Kingdom