potoroo99
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- Posted: Thu, 25 Jan 2007 01:36:44 +0000
global dimming
Summary
the opposite of global warming is happening now, but its effects are not as strong as the effects of global warming so the temperature will still rise
nobody ever talks about it and it is really important,
i have been studying this subject in my A level environmental science classes and was surprised that it is not generally mentioned in the media
simple summary - poluting particles in the air from burning things that cotain carbon (fossil feuls, wood) are reflecting radiation back into space and keeping us cool, when we run out or finally manage to stop using fossil feuls, this effect will be cancelled out and the global temperature is estimated to rise by 5-6'C, which is more than the av. temp has changed in the last 400,000 years.
so i think we are preventing ourselves seeing the true effects of global warming with our own pollution
end of summary
____________________________________________________________
last major piece of evidence collected
septmber 11th, when the twin towers came down, planes were banned near the city for 3 days, the lack of aviation fumes in the atmosphere made the temperature increase over only those 3 days, this was the highest recorded temperature in september for over 135years, and that year the whole of september was warmer anyway.
people have been also measuring how much water evapourates from a pan in 24 hours for 100s of years, if you show pan evapouration against temperature, it shows that the evapouration goes down, even though the temperature stays the same with the increase in pollution in the atmosphere, i should try and find a graph to show this. they have since proven that light is more important than heat in evapouration
(shorter wavelength of radiation = more molecule movement = more evapouration)
many people argue it could have been a coincidence, but you can't ignor a ''cioncidence' like that.
for some nice pictures and animations see
http://www.sflorg.com/earthnews/en041706_01.html
for more scientific evidence behind this theory
if you want to read more see
http://en.wikipedia.org/wiki/Global_dimming
http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_prog_summary.shtml
please consider the evidence before saying whether or not you believe it exists or not.
i hope what i have said makes sense, please correct me if you don't understand
anyway, this is a discussion related to global warming and global dimming.
my scientific explaination
according to my studies, the more in depth explaination of global dimming is based on the dust particles from smoke etc. when a raindrop forms in the atmosphere, the water vapour needs to condense onto something, it condenses onto a carbon particle. if cloud is formed containing many smaller raindrops instead of fewer larger drops (when there is a limited supply of condensation nuclei) , they clouds is much more reflective. these reflect visible light energy (which later is converted to heat energy in the ground), this energy has not got to the stage where global warming is concerned yet. so, both processes can happen at once.
evidence, much of the global dimming evidence is in the form of evapouration records, it has been recently discovered that visible light causes water to evapourate more than heat does (think microwaves, even shorter wavelength, even more evapouration). over many many years, meteorologists all over the world have been measuring evapouration in pan over 24hours. they have discovered that evapouration rates have dropped in places where temperatures have stayed the same, photosynthesis rates have also dropped due to lower light intensity
this is a trend that has been measure for a long time, and hasn't got anything to do with daily weather patterns
(i have used english UK spelling, so if any of it wrong in american spelling, i apologise)
ok - questions for debate
1.) after reading this information, do you believe global dimming exists?
2.) does global dimming change your view on global warming?
3.) do you think this topic deserves more media coverage?
Summary
the opposite of global warming is happening now, but its effects are not as strong as the effects of global warming so the temperature will still rise
nobody ever talks about it and it is really important,
i have been studying this subject in my A level environmental science classes and was surprised that it is not generally mentioned in the media
simple summary - poluting particles in the air from burning things that cotain carbon (fossil feuls, wood) are reflecting radiation back into space and keeping us cool, when we run out or finally manage to stop using fossil feuls, this effect will be cancelled out and the global temperature is estimated to rise by 5-6'C, which is more than the av. temp has changed in the last 400,000 years.
so i think we are preventing ourselves seeing the true effects of global warming with our own pollution
end of summary
____________________________________________________________
last major piece of evidence collected
septmber 11th, when the twin towers came down, planes were banned near the city for 3 days, the lack of aviation fumes in the atmosphere made the temperature increase over only those 3 days, this was the highest recorded temperature in september for over 135years, and that year the whole of september was warmer anyway.
people have been also measuring how much water evapourates from a pan in 24 hours for 100s of years, if you show pan evapouration against temperature, it shows that the evapouration goes down, even though the temperature stays the same with the increase in pollution in the atmosphere, i should try and find a graph to show this. they have since proven that light is more important than heat in evapouration
(shorter wavelength of radiation = more molecule movement = more evapouration)
many people argue it could have been a coincidence, but you can't ignor a ''cioncidence' like that.
for some nice pictures and animations see
http://www.sflorg.com/earthnews/en041706_01.html
for more scientific evidence behind this theory
if you want to read more see
http://en.wikipedia.org/wiki/Global_dimming
http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_prog_summary.shtml
please consider the evidence before saying whether or not you believe it exists or not.
i hope what i have said makes sense, please correct me if you don't understand
anyway, this is a discussion related to global warming and global dimming.
my scientific explaination
according to my studies, the more in depth explaination of global dimming is based on the dust particles from smoke etc. when a raindrop forms in the atmosphere, the water vapour needs to condense onto something, it condenses onto a carbon particle. if cloud is formed containing many smaller raindrops instead of fewer larger drops (when there is a limited supply of condensation nuclei) , they clouds is much more reflective. these reflect visible light energy (which later is converted to heat energy in the ground), this energy has not got to the stage where global warming is concerned yet. so, both processes can happen at once.
evidence, much of the global dimming evidence is in the form of evapouration records, it has been recently discovered that visible light causes water to evapourate more than heat does (think microwaves, even shorter wavelength, even more evapouration). over many many years, meteorologists all over the world have been measuring evapouration in pan over 24hours. they have discovered that evapouration rates have dropped in places where temperatures have stayed the same, photosynthesis rates have also dropped due to lower light intensity
this is a trend that has been measure for a long time, and hasn't got anything to do with daily weather patterns
(i have used english UK spelling, so if any of it wrong in american spelling, i apologise)
ok - questions for debate
1.) after reading this information, do you believe global dimming exists?
2.) does global dimming change your view on global warming?
3.) do you think this topic deserves more media coverage?
