“Business as usual” could lead to catastrophic global sea-level rise, says new study

As hurricane season bears down on many people and communities this month, one of the key factors linked to increasing severity of a storm’s impacts—sea level rise—sees new predictions emerge for “worst-case scenarios”.

Mathematicians and scientists calculate likely and possible outcomes based on probabilities, with computers able to crunch ever-larger volumes of data to come up with more accurate predictions.

Climate modelling has improved enormously in the past 20 years, and where predictions of catastrophe are distinct—as opposed to remote—we should take note.

A 5°C temperature rise is consistent with unchecked emissions growth.

Such a rise over the next 80 years could trigger the gradual displacement of millions of people around the world and swallow up an area of land three times the size of Texas.

Under a “business as usual” scenario where temperatures rise by 5°C, the picture is even grimmer beyond 2100, with a projected increase by 7.5 metres.

A New Climate for Peace: Taking Action on Climate and Fragility Risks, commissioned by members of the G7 group of nations, outlines seven “climate-fragility” risks that pose serious threats to global stability in the next decades.

One of the risks identified is rising sea levels: “Rising sea levels are threats to the economic and physical viability of low-lying areas, as land and coastal resources are gradually lost. This can lead to social disruption, displacement and migration, as well as disagreements over maritime boundaries and ocean resources.”

Through its Joint Unit with the UN Office for the Coordination of Humanitarian Affairs, UNEP at the request of governments, seconds disaster assessment experts to areas affected by climate-related emergencies. This was the case in 2017, after Hurricane Maria struck Dominica and Puerto Rico, as well as in April 2019 after cyclones Idai and Kenneth hit Mozambique.

In collaboration with United Nations Office for Project Services (UNOPS), and with funding from the Global Environment Facility, UNEP supported the Government of Tanzania to build extensive seawalls along the country’s coast, including over 2,400m of defence structures. The project, which was completed in June 2018, was part of a broader UNEP initiative to build climate resilience by improving natural ecosystems.

The climate crisis is gaining the attention of the world’s media and politicians. Several countries have declared climate emergencies, and climate emergency declarations have reportedly been made in several hundred jurisdictions and local governments covering over 100 million citizens.

Nineteen countries and 32 cities have joined the Carbon Neutrality Coalition, committing to take concrete and ambitious action to achieve the aims of the Paris Climate Agreement. This means they aim to be carbon neutral by 2050.

Over 6 million people currently live in coastal areas vulnerable to sea-level rise today. Even in a 2°C global heating scenario, 10 million more would be affected, according to the Intergovernmental Panel on Climate Change.

Original source: UNEP
Published on 11 September 2019