Can global dimming fix global warming?
Posted by Hudson DeWeese on Wed, Jun 23, 2010
The particles released into the atmosphere from aerosols and planes are actually reflecting sunlight back into space which is found to have the effect of cooling the earth. During the three days that followed September 11th, 2001, it was noticed that the average daytime temperature increased by 1.8°F, which proves the significance of what is called global dimming. Some believe that global dimming can be used to as a geoengineering technique to reduce the impact of global warming when in reality it is a cheap and temporary fix to combat global warming.
The full temperature effects of global dimming are not yet fully understood due to the challenge of recording the overall temperature of the earth's atmosphere. Regions that are downwind from major sources of air pollution have generally cooled, which makes global dimming intriguing. This may also explain why the eastern United States is cooling compared to the warming western part.
Aerosols generally have a life of one week until they get collected by rain and fall to the earth's surface. While in the atmosphere, aerosols have a cooling effect by reflecting sunlight back into space while during the nighttime it actually prevents the earth from cooling by trapping the heat in. It has also been noticed that aerosols can decrease rain fall which interferes with the hydrological cycle. In general, most techniques of temporarily cooling the earth's atmosphere have a cooling effect in some regions but a heating effect in others giving no overall change in the earth's climate. For example, volcanic ash has been shown to cool down the atmosphere in a similar way aerosols do, but once the ash settles it absorbs sunlight which in return heats the atmosphere.
The use of green energy reduces the amount of sulfides and CO2 in the atmosphere which has a direct relationship to global warming, which as a result is cooling the earth. Where global dimming is just masking these effects for a temporary amount of time and has yet to be proven effective past regional effects. Although green energy doesn't have an immediate effect on the climate like a volcanic eruption does, there is proof that green energy works with no repercussions of having the earth warm in any other areas.