Organic vapors affect clouds leading to previously unidentified climate cooling

May 05, 2013
Cloud in Nepali sky. Credit: Wikipedia

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

Clouds are made of , condensed on to suspended in the air. When the air is humid enough, the particles swell into . 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 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 manmade 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 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 , 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."

Explore further: Mexico's Volcano of Fire blows huge ash cloud

More information: Cloud droplet number enhanced by co-condensation of organic vapours, DOI: 10.1038/ngeo1809

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User comments : 16

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ForFreeMinds
2.1 / 5 (14) May 05, 2013
I won't be holding my breath for AGW proponents to propose we increase the amount of the man made pollution that increases cooling that we release into the air. Are they for keeping the temperatures as is, or for man not polluting? I think it's the latter.
deepsand
3.4 / 5 (17) May 05, 2013
I won't be holding my breath for AGW proponents to propose we increase the amount of the man made pollution that increases cooling that we release into the air. Are they for keeping the temperatures as is, or for man not polluting? I think it's the latter.

Fallacy of the excluded middle.
HannesAlfven
1.7 / 5 (11) May 06, 2013
This article is written from the mechanistic worldview which Rupert Sheldrake has been warning about. I personally find it fascinating that the focus is upon the cloud brightness rather than on the fact that many, many tons of water are apparently hovering above our heads.

What keeps it up there, to begin with?

Oh yeah, there is a mechanistic explanation for that as well ...
deepsand
3.4 / 5 (17) May 06, 2013
This article is written from the mechanistic worldview which Rupert Sheldrake has been warning about. I personally find it fascinating that the focus is upon the cloud brightness rather than on the fact that many, many tons of water are apparently hovering above our heads.

What keeps it up there, to begin with?

If you need to ask you've no business posting here.
djr
4 / 5 (8) May 06, 2013
"What keeps it up there, to begin with?"

It is a total mystery - if you ever figure it out - you will become world famous. Next you have to work on airplanes - god only knows what keeps those buggers up there.
HealingMindN
1.5 / 5 (8) May 06, 2013
I have a silly idea: What about if we transition more towards green energy and super efficient energy technology - then have those scientists measure the further brightness of clouds again in about ten years. Meanwhile, those scientists can get it together with their polluting, big industry buddies and figure out the next article entitled, "How farts and VOCs have the same effect."
deepsand
3.4 / 5 (15) May 07, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?
antigoracle
1.4 / 5 (11) May 11, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.
deepsand
3.2 / 5 (13) May 11, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.

This from one who thinks that his fixation with fecal matter is relevant to discussions of matter of Science. :rolleyes:
antigoracle
1.4 / 5 (11) May 13, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.

This from one who thinks that his fixation with fecal matter is relevant to discussions of matter of Science. :rolleyes:
-- deepsandTurd aka FecalMatter
You must think highly of yourself to claim I have a fixation with you. I challenge all stupidity, not just you.
Maggnus
5 / 5 (3) May 13, 2013
You must think highly of yourself to claim I have a fixation with you. I challenge all stupidity, not just you.


You must have some pretty interesting conversations when you're brushing your tooth then.
deepsand
3 / 5 (12) May 13, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.

This from one who thinks that his fixation with fecal matter is relevant to discussions of matter of Science. :rolleyes:
-- deepsandTurd aka FecalMatter
You must think highly of yourself to claim I have a fixation with you. I challenge all stupidity, not just you.

TROLL CRAP.
antigoracle
1.4 / 5 (10) May 15, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.

This from one who thinks that his fixation with fecal matter is relevant to discussions of matter of Science. :rolleyes:
-- deepsandTurd aka FecalMatter
You must think highly of yourself to claim I have a fixation with you. I challenge all stupidity, not just you.

TROLL CRAP.

Ah the response of an AGW ReTURD confirms the limits of a lone neuron.
deepsand
3 / 5 (12) May 16, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.

This from one who thinks that his fixation with fecal matter is relevant to discussions of matter of Science. :rolleyes:
-- deepsandTurd aka FecalMatter
You must think highly of yourself to claim I have a fixation with you. I challenge all stupidity, not just you.

TROLL CRAP.

Ah the response of an AGW ReTURD confirms the limits of a lone neuron.

Not our fault that you can't count beyond one.
Neinsense99
3 / 5 (8) May 26, 2013
"What keeps it up there, to begin with?"

It is a total mystery - if you ever figure it out - you will become world famous. Next you have to work on airplanes - god only knows what keeps those buggers up there.


Wing tanks filled with woo, apparently.
Neinsense99
3 / 5 (8) May 26, 2013
I've an even sillier idea. How about we figure out how to keep the idiots who know nothing about Science from posting here?

Uh huh, so that AGW Alarmist Turds, like yourself, would not make such "brilliant" scientific comments.

This from one who thinks that his fixation with fecal matter is relevant to discussions of matter of Science. :rolleyes:
-- deepsandTurd aka FecalMatter
You must think highly of yourself to claim I have a fixation with you. I challenge all stupidity, not just you.


'I am challenged by stupidity.' There, fixed that for you.

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