
Sea levels around the world rose at an average rate of 1.5 millimetres a year since 1880, but studies of tidal marshes in Tasmania show a rise of 4.2mm a year between 1900 and 1950. "Sea levels in Tasmania remained relatively stable for much of the past 6000 years, but around 1880 they started rising drastically," said Dr Moss, who co-wrote the study in conjunction with scientists from the UK, New Zealand and Australia.
Dr Moss said a jump in sea levels occurred after 1990. "The rise in 1910 probably reflects the end of the little ice age, when temperatures were about one to two degrees cooler in the northern hemisphere than today," he said. "The 1990s peak is most likely indicative of human-induced climate change."
While debate exists over whether the increasing depths of the oceans is a result of thermal expansion of existing water or the melting of ice, the ultimate cause is undoubtedly global warming. Dr Moss said research suggests the earth has been free of ice at various periods during its existence, at which times sea levels could have been as much as 90-100 metres higher than today....
Stumpy's Bay beach in Tasmania, shot by Srikumar Venugopal, Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license
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