Featured Research

from universities, journals, and other organizations

Brighter clouds, cooler climate? Organic vapors affect clouds, leading to previously unidentified climate cooling

Date:
May 5, 2013
Source:
Manchester University
Summary:
Scientists have shown that natural emissions and humanmade pollutants can both have an unexpected cooling effect on Earth's climate by making clouds brighter.

Natural emissions and humanmade pollutants can both have an unexpected cooling effect on the world's climate by making clouds brighter.
Credit: Yuriy Kulik / Fotolia

University of Manchester scientists, writing in the journal Nature Geoscience, have shown that natural emissions and humanmade pollutants can both have an unexpected cooling effect on Earth's climate by making clouds brighter.

Related Articles


Clouds are made of water droplets, condensed onto tiny particles suspended in the air. When the air is humid enough, the particles swell into cloud droplets. It has been known for some decades that the number of these particles and their size control how bright the clouds appear from the top, controlling the efficiency with which clouds scatter sunlight back into space. A major challenge for climate science is to understand and quantify these effects which have a major impact in polluted regions.

The tiny seed particles can either be natural (for example, sea spray or dust) or humanmade pollutants (from vehicle exhausts or industrial activity). These particles often contain a large amount of organic material and these compounds are quite volatile, so in warm conditions exist as a vapour (in much the same way as a perfume is liquid but gives off an aroma when it evaporates on warm skin).

The researchers found that the effect acts in reverse in the atmosphere as volatile organic compounds from pollution or from the biosphere evaporate and give off characteristic aromas, such as the pine smells from forest, but under moist cooler conditions where clouds form, the molecules prefer to be liquid and make larger particles that are more effective seeds for cloud droplets.

"We discovered that organic compounds such as those formed from forest emissions or from vehicle exhaust, affect the number of droplets in a cloud and hence its brightness, so affecting climate," said study author Professor Gordon McFiggans, from the University of Manchester's School of Earth, Atmospheric and Environmental Sciences.

"We developed a model and made predictions of a substantially enhanced number of cloud droplets from an atmospherically reasonable amount of organic gases.

"More cloud droplets lead to brighter cloud when viewed from above, reflecting more incoming sunlight. We did some calculations of the effects on climate and found that the cooling effect on global climate of the increase in cloud seed effectiveness is at least as great as the previously found entire uncertainty in the effect of pollution on clouds."


Story Source:

The above story is based on materials provided by Manchester University. Note: Materials may be edited for content and length.


Journal Reference:

  1. David Topping, Paul Connolly, Gordon McFiggans. Cloud droplet number enhanced by co-condensation of organic vapours. Nature Geoscience, 2013; DOI: 10.1038/ngeo1809

Cite This Page:

Manchester University. "Brighter clouds, cooler climate? Organic vapors affect clouds, leading to previously unidentified climate cooling." ScienceDaily. ScienceDaily, 5 May 2013. <www.sciencedaily.com/releases/2013/05/130505145839.htm>.
Manchester University. (2013, May 5). Brighter clouds, cooler climate? Organic vapors affect clouds, leading to previously unidentified climate cooling. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2013/05/130505145839.htm
Manchester University. "Brighter clouds, cooler climate? Organic vapors affect clouds, leading to previously unidentified climate cooling." ScienceDaily. www.sciencedaily.com/releases/2013/05/130505145839.htm (accessed October 31, 2014).

Share This



More Earth & Climate News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

World's Salamanders At Risk From Flesh-Eating Fungus

World's Salamanders At Risk From Flesh-Eating Fungus

Newsy (Oct. 31, 2014) The import of salamanders around the globe is thought to be contributing to the spread of a deadly fungus. Video provided by Newsy
Powered by NewsLook.com
Controversial French Dam Halted After Death of Protester

Controversial French Dam Halted After Death of Protester

AFP (Oct. 31, 2014) Local French authorities Friday decided to suspend work on a controversial dam after the death last week of an activist protesting against the project that sparked uproar in the country. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
How A Chorus Led Scientists To A New Frog Species

How A Chorus Led Scientists To A New Frog Species

Newsy (Oct. 30, 2014) A frog noticed by a conservationist on New York's Staten Island has been confirmed as a new species after extensive study and genetic testing. Video provided by Newsy
Powered by NewsLook.com
Raw: Hawaii Lava Inches Closer

Raw: Hawaii Lava Inches Closer

AP (Oct. 30, 2014) Aerial video shows the path lava has carved across a portion of Hawaii's big island, threatening homes in the town of Pahoa. Officials say the flow was just over 230 yards from a roadway Thursday morning. (Oct. 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins