Tags: Global | Warming | Cities | Carbon | Sinks

Global Warming: Cities, Too, Are Carbon 'Sinks'

Tuesday, 12 Jul 2011 08:32 AM

 

  Comment  |
   Contact  |
  Print   |
    A   A  
  Copy Shortlink
Scientists on Tuesday offered a slender piece of good news about global warming, reporting that cities can be of surprising help in soaking up carbon dioxide (CO2), the principal greenhouse gas.

Around four percent of the world's land surface is defined as urbanised, a figure expected to surge as the planet's human population rises from seven billion this year to as much as 9.5 billion by mid-century.

But unlike forests, urban areas are absent in most calculations of "sinks" where vegetation soaks up CO2 naturally thanks to photosynthesis.

A new study, though, says the contribution can be significant.

British scientists carried out their survey on the central English city of Leicester, which has a population of around 300,000 living in an area of 73 square kilometres (28 square miles).

They measured the carbon-absorbing capacity of its parks, domestic gardens, abandoned industrial land, golf courses, school playing fields, road verges and river banks.

They found that 231,000 tonnes of carbon were locked up this way, 10 times more than expected. It is roughly equal to the average annual emissions of more than 150,000 saloon, also called sedan, cars.

"Currently, once land in the UK is considered to be urban, its biological carbon density is assumed to be zero," said researcher Zoe Davies of the University of Kent, southeast England.

"Our study illustrates this is not the case and that there is a substantial pool of carbon locked away in the vegetation within a city."

Urban "sinks" are not by themselves a solution to the billions of tonnes of carbon emitted globally but can help mitigate their impact, especially if gardeners grow trees, which absorb far more CO2 than grass and shrubs, she said.

In the case of Leicester, most of the publicly-owned or -managed land in the city comprises lawns. But if just 10 percent of this land were planted with trees, the city's carbon storage would leap by 12 percent.

"If more trees are planted in urban areas for their carbon storage value, they must be the right kind of tree planted in the right place so that they have a long, productive lifespan, and when trees die they should be replaced," Davies cautioned.

Trees have an additional benefit of lowering the temperature locally, providing shade. In contrast, asphalt roads and buildings store solar radiation during the day, encouraging the creation of "urban heat islands" that can add dangerously to the effect of heatwaves on human health.

The new study appears in the Journal of Applied Ecology, published by the British Ecological Society.

© AFP 2014

  Comment  |
   Contact  |
  Print   |
  Copy Shortlink
Around the Web
Join the Newsmax Community
Please review Community Guidelines before posting a comment.
>> Register to share your comments with the community.
>> Login if you are already a member.
blog comments powered by Disqus
 
Email:
Country
Zip Code:
Privacy: We never share your email.
 
Follow Newsmax
Like us
on Facebook
Follow us
on Twitter
Add us
on Google Plus
Around the Web
Top Stories
You May Also Like

German Researchers: Cellphone Calls, Messages Easy to Crack

Friday, 19 Dec 2014 14:12 PM

Security flaws on the global network that routes the world's cellphone calls and texts could allow hackers and criminals . . .

Kepler's Exoplanet Find Is First Since Space Telescope Revived

Friday, 19 Dec 2014 09:54 AM

The Kepler space telescope has discovered its first exoplanet since NASA's engineers were able to reboot the mission man . . .

Rosetta Comet-Landing Is 2014's Top Science Breakthrough

Friday, 19 Dec 2014 08:37 AM

The top scientific breakthrough of 2014 was the European Space Agency's Rosetta spacecraft's rendezvous with a comet, th . . .

Most Commented

Newsmax, Moneynews, Newsmax Health, and Independent. American. are registered trademarks of Newsmax Media, Inc. Newsmax TV, and Newsmax World are trademarks of Newsmax Media, Inc.

 
NEWSMAX.COM
America's News Page
©  Newsmax Media, Inc.
All Rights Reserved