Study predicts massive sea level rise from global warming

Even a small increase of 143 cm in sea level has consequences for tourism in Venice, Italy. Keystone

A study from Switzerland and the United States looking at the effects of climate change in the next 10,000 years predicts that sea levels will rise by as much as 50 metres.

Ongoing greenhouse gas emissions could have drastic and irreversible repercussions which will only be visible over an extended period, said researchers from the University of Bern and the University of Oregon in the US in a study released on Monday by the scientific journal Nature Climate Change.

Rather than just looking at the 21st century, the new study developed four potential scenarios for the next 10,000 years. If no measures are taken to slow global warming and the temperature of the earth climbs to seven degrees greater than in the pre-industrial period, the sea level could rise as much as 50 metres, said the scientists.

Even if it is possible to limit the increase in the earth’s temperature to two degrees Celsius – the goal set at the United Nations climate conference held in Paris at the end of 2015 – the group calculated a long-term increase in sea level of up to 25 metres.

Today, said the authors, there are 122 countries in which at least 10% of the population would be directly affected by the increase in sea level.

“We can’t build 25-metre-high walls,” said lead author Peter Clark of the University of Oregon. “Whole mega-cities will have to be moved.”

According to author Thomas Stocker of the University of Bern, all efforts have to focus on a quick and complete de-carbonisation of energy systems. That is the only option for effectively limiting the effects of climate change, he said.

According to the authors, debate thus far over the future effects of global warming and the rising sea level has been too shortsighted. Political discussion is usually limited to looking back over the past 150 years and forward only to the end of the century.

“It’s high time that politicians acknowledge the enormous longevity of the climate problem,” said Stocker. “Small and temporary reductions in emissions are not enough.”