Trans Scan: a global scan of emerging trends in mobility and the built environment

Coastal disasters according to Stern

Britain’s Stern report on climate change does much to concentrate the mind on what the world could be facing. The graph above taken from the report shows dramatically how global temperatures could rise between now and the end of the 21st Century.

In his report, Sir Nicholas Stern also provides a table of “impacts” describing what each degree of temperature increase could have on water, food, health, land, and the environment. For example, a one-degree increase sees glaciers in the Andes disappear and threatens the water supplies of 50 million people.

At the same time, 80% of the Great Barrier Reef would suffer bleaching. Two degrees up and an extra 10 million people a year will be hit by coastal flooding while in Southern Africa and the Mediterranean water availability would drop by 20–30%. Three degrees up and 1–4 billion people suffer water shortages while around the world up to 170 million people would face coastal flooding. Four degrees up and coastal flooding hits 300 million people annually. Five degrees up and the glaciers of the Himalayas will disappear threatening the water supplies of a quarter of China’s population.

By that time too low-lying coastal cities like New York, London and Tokyo would be battling to keep the sea out. Although the graph show that some models predict temperatures rising above five degrees before the end of the century, Stern does not predict what might happen. He says it would just lead to “catastrophic effects.”