Stories
Slash Boxes
Comments

SoylentNews is people

posted by janrinok on Tuesday October 11 2016, @08:23PM   Printer-friendly
from the overcast-with-a-chance-of-light-wood dept.

The pre-industrial atmosphere contained more particles, and so brighter clouds, than we previously thought. This is the latest finding of the CLOUD experiment, a collaboration between around 80 scientists at the CERN particle physics lab near Geneva. It changes our understanding of what was in the atmosphere before humans began adding pollution – and what it might be like again in the future.

Most cloud droplets need tiny airborne particles to act as "seeds" for their formation and growth. If a cloud has more of these seeds, and therefore more droplets, it will appear brighter and reflect away more sunlight from the Earth's surface. This in turn can cool the climate. Therefore understanding the number and size of particles in the atmosphere is vital to predicting not only how bright and reflective the planet's clouds are, but what global temperatures will be.
...
The CLOUD experiment at CERN also recently discovered that gases emitted by trees can stick together to make new seeds for clouds in the atmosphere – without needing any help from other pollutants as was previously thought. Scientists had thought that the cloud seeds needed sulphuric acid (often mixed with other compounds) or iodine molecules to stick together to initiate the process.

In our new follow-up study, published in PNAS, we worked with other CLOUD scientists to simulate this process in the atmosphere. Our work suggests that even today trees produce a large fraction of cloud seeds over the cleanest forested parts of the world.

More trees means more clouds, which means cooler Earth.


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 5, Informative) by fishybell on Tuesday October 11 2016, @11:38PM

    by fishybell (3156) on Tuesday October 11 2016, @11:38PM (#413165)

    More trees means more clouds, which means cooler Earth.

    Whoa there. There is so much more nuance to clouds' interactions on warming and cooling.

    First off, different clouds [nsf.gov] behave in different ways. Some (ie. stratus, cumulus) reflect light creating a net cooling effect. Some (ie. cirrus) let enough light through to counteract any reflectivity they have while trapping heat as all clouds do, to a net effect of contributing to warming.

    Second, H20 is the single most significant [nasa.gov] (in its effect) greenhouse gas and with warming temperatures, less water vapor is going to end up binding together with other molecules in the air to make a cloud. The water vapor capacity of air raises with temperature [gccaz.edu], which increases the supersaturation point at which clouds form [wikipedia.org].

    Starting Score:    1  point
    Moderation   +3  
       Informative=3, Total=3
    Extra 'Informative' Modifier   0  
    Karma-Bonus Modifier   +1  

    Total Score:   5  
  • (Score: 0) by Anonymous Coward on Wednesday October 12 2016, @03:18AM

    by Anonymous Coward on Wednesday October 12 2016, @03:18AM (#413246)

    Also, Venus is quite cloudy but not particularly cool, IIRC.

    • (Score: 0) by Anonymous Coward on Wednesday October 12 2016, @03:26AM

      by Anonymous Coward on Wednesday October 12 2016, @03:26AM (#413248)

      > Also, Venus is quite cloudy but not particularly cool, IIRC.

      Hey Pinky! What are we going to do today?
      Move the world to the orbit of Venus!