Earth facing dire sea level rise — up to 20m — even if climate goals met

globalnews.ca:

Capping global temperature rise at two degrees Celsius over baseline is no longer seen as enough to avoid a catastrophic rise in sea levels that would decimate the earth’s coastlines and displace hundreds of millions of people, climate scientists warn.

A report released Thursday by the International Cryosphere Climate Initiative, compiled by more than 60 scientists and policy experts, is sounding the alarm on new modelling data that indicates the 2015 Paris Agreement is woefully out-of-date.

The consortium is urging world leaders to take stock of new research ahead of the United Nations’ COP28 climate conference later this month. According to the report, the only road forward is ensuring that global temperatures do not rise over 1.5C above pre-industrial levels, much lower than the two degree maximum set at the Paris Climate Accords.

“We have time, but not much time,” reads the report’s preface, written by the president of Chile and prime minister of Iceland. “We cannot negotiate with the melting point of ice.”

If global average temperatures rise by two degrees, the Earth faces a sea-level rise of more than 12 metres, or 40 feet — and that’s the conservative estimate.

The report states sea levels could rise up to 20 metres, or 65 feet, citing a “compelling number of new studies, taking into account ice dynamics, paleo-climate records from Earth’s past, and recent observations of ice sheet behavior.”

If this is allowed to happen, the planet faces “extensive coastal loss and damage well beyond limits of feasible adaption,” the report warns.

This melt would take place over decades, even centuries, but would result in a dramatic reshaping of the earth’s coastlines.

During a February meeting at the UN, Secretary-General