By Alister Doyle, Environment Correspondent
OSLO, April 14 (Reuters) - The world's urban areas are set to grow by almost twice the size of Manhattan a day until 2030 and the design of future cities in Asia and Africa will be crucial to slow global warming, a U.N. study showed on Monday.
The breakneck expansion means billion-dollar opportunities for companies, ranging from greener construction of homes and offices to improved rail and bus networks, according to a report by the U.N.'s Intergovernmental Panel on Climate Change (IPCC).
"There is a window of opportunity" to enlist urban design to slow global warming, said Karen Seto, a professor at Yale University who co-led a chapter about city planning in a 2,000-page IPCC report about slowing climate change.
A 33-page IPCC summary - with a photo of Shanghai on the cover - was issued on Sunday. It said yet-to-be-built cities could help slow warming but most details are in a 116-page chapter, obtained by Reuters before publication on Tuesday.
In one scenario, urban expansion from 2000 to 2030 will add 1.2 million sq kms (460,000 sq miles) to towns and cities, mostly in Asia and Africa and more than the total urban land in 2000 of about 650,000 sq kms (250,000 sq miles), it says.
That expansion works out at 110 sq kms (42 sq miles) every day for three decades, almost twice the size of Manhattan or 20,000 American football fields.
"20,000 football fields will go from being farms to cities, from being forests to cities, every day," Seto told Reuters. And urban areas account for between 71 and 76 percent of the world's carbon dioxide emissions from energy, it said.
More compact city designs that cut commutes, insulation to save energy, better public transport, cycle lanes and pedestrian areas can all cut emissions, mainly from fossil fuels.
Problems include a lack of planning regulations, especially in developing nations, where opportunities for limiting future greenhouse gases are highest and which could also benefit from curbs on fossil fuels to reduce air pollution.
In 1800, only Beijing had more than a million inhabitants and cities and towns were home to three percent of the world population. By 2010, 449 cities had more than a million inhabitants and 52 percent of all people lived in urban areas.
"Each week the global urban population increases by 1.3 million," the chapter said. By 2050, the urban population is likely to rise to about two-thirds of everyone on Earth.
Once built, cities can be hard to shift to greener policies. "If you live in the average North American city you are a long way from buying a loaf of bread or where you work and you have to use a car," Seto said.
The IPCC's summary said that swifter action is needed to limit global warming to an agreed ceiling of 2 degrees Celsius (3.6 Fahrenheit) above pre-industrial times, seen as a threshold for ever more damaging heatwaves, floods and rising seas.
A previous IPCC report in September said the probability that human emissions of greenhouse gases, rather than natural variations in the climate, were the dominant cause of warming since 1950 had risen to at least 95 percent from 90 percent previously.
A report last week by the Institute for Transportation and Development Policy said that urban projects such as London's Central Saint Giles, Hammarby Sjöstad in Stockholm and Liuyun Xiaoqu in Guangzhou, China, were good examples of low-emissions developments. (Reporting By Alister Doyle; Editing by Tom Heneghan)
Our 2024 Coverage Needs You
It's Another Trump-Biden Showdown — And We Need Your Help
The Future Of Democracy Is At Stake
Our 2024 Coverage Needs You
Your Loyalty Means The World To Us
As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.
Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.
Contribute as little as $2 to keep our news free for all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
The 2024 election is heating up, and women's rights, health care, voting rights, and the very future of democracy are all at stake. Donald Trump will face Joe Biden in the most consequential vote of our time. And HuffPost will be there, covering every twist and turn. America's future hangs in the balance. Would you consider contributing to support our journalism and keep it free for all during this critical season?
HuffPost believes news should be accessible to everyone, regardless of their ability to pay for it. We rely on readers like you to help fund our work. Any contribution you can make — even as little as $2 — goes directly toward supporting the impactful journalism that we will continue to produce this year. Thank you for being part of our story.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
It's official: Donald Trump will face Joe Biden this fall in the presidential election. As we face the most consequential presidential election of our time, HuffPost is committed to bringing you up-to-date, accurate news about the 2024 race. While other outlets have retreated behind paywalls, you can trust our news will stay free.
But we can't do it without your help. Reader funding is one of the key ways we support our newsroom. Would you consider making a donation to help fund our news during this critical time? Your contributions are vital to supporting a free press.
Contribute as little as $2 to keep our journalism free and accessible to all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.
Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.
Contribute as little as $2 to keep our news free for all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
Dear HuffPost Reader
Thank you for your past contribution to HuffPost. We are sincerely grateful for readers like you who help us ensure that we can keep our journalism free for everyone.
The stakes are high this year, and our 2024 coverage could use continued support. Would you consider becoming a regular HuffPost contributor?
Dear HuffPost Reader
Thank you for your past contribution to HuffPost. We are sincerely grateful for readers like you who help us ensure that we can keep our journalism free for everyone.
The stakes are high this year, and our 2024 coverage could use continued support. If circumstances have changed since you last contributed, we hope you'll consider contributing to HuffPost once more.
Support HuffPostAlready contributed? Log in to hide these messages.