Billions of city-dwellers at risk from climate impacts by 2050, report warns
Londoners will be among billions of city-dwellers facing effects of climate change such as floods and blackouts by 2050, research has warned.
People in thousands of the world's large cities face problems caused by rising temperatures including heatwaves, flooding, food and water shortages and blackouts by mid-century without urgent action to curb greenhouse gases.
It is "the future that nobody wants" warns the study by C40 Cities, a group of cities taking action on climate change, the Global Covenant of Mayors, the Urban Climate Change Research Network and climate advisory company Acclimatise.
But authorities in cities around the world are taking steps to protect their citizens from the impacts of climate change, the study said.
Rising sea levels, storm surges and more rain mean London, the UK's largest city, faces the threat of tidal, river and flash flooding.
But the city is also vulnerable to overheating and drought-like conditions, while hotter summers increase demand for air conditioning, putting more pressure on energy supplies.
UK power plants supplying London are located around the coast and are vulnerable to flooding which could lead to blackouts, while electricity substations in the city are also at risk of local floods, the report said.
The impacts of climate change could put assets worth £200 million at risk and threaten 1.25 million people who live along the Thames River in London and the surrounding areas, the study warned.
But London is improving its drainage to help infrastructure withstand heavy flooding and encouraging more small-scale "decentralised" energy, including renewables, to reduce the risk of blackouts if one power source is hit.
Worldwide, 70% of cities are already dealing with the effects of climate change, and nearly all are at risk, the report warned.
More than 800 million city-dwellers will be vulnerable to sea level rises and coastal flooding by 2050, including 30 million in European cities, and 470 million will face power supplies at risk from rising seas.
Around 650 million people will be at risk of water shortages as a result of climate change, including in Athens and Madrid, and 1.6 billion people living in 970 cities, will be regularly exposed to extreme high temperatures.
And 2.5 billion people will be living in cities where national food supplies are threatened by climate change, including residents of Barcelona, Moscow and Oslo.
Mark Watts, executive director of C40 Cities said: "For decades, scientists have been warning of the risks that climate change will pose from increasing global temperatures, rising sea levels, growing inequality and water, food and energy shortages.
"Now we have the clearest possible evidence of just what these impacts will mean for the citizens of the world's cities.
"This is the future that nobody wants. Our research should serve as a wake-up call on just how urgently we need to be delivering bold climate action."
Actions cities around the world are taking to address climate change include planting 16 million trees and expanding green areas in Seoul, South Korea and improving coastal defences in New York.
And Paris has plans to establish 33 hectares (80 acres) of urban agriculture within the city's boundaries by 2020 to improve food security.