The Earth is warmed principally by the sun’s radiation which enters the atmosphere. However, not all the radiation penetrates the atmosphere as some is scattered back into space. The amount of back-scattering into space alters the amount of energy that is absorbed into the atmosphere. backscattering of this energy provides valuable information on the change of the earth’s radiation balance and how different activities (artificial and anthropogenic) can affect this delicately balanced system and thus influence global warming.

Studies have found that natural and man-made aerosols in the earth’s atmosphere can influence the rate of global warming through their ability to reflect radiant energy. One study performed during the 9/11 terrorist attacks in the USA showed that when all air traffic was stopped for a three day period at the height of those emergency days, the earth’s surface temperature increased www.cnn.com/2002/TECH/science/08/07/contrails.climate/index.html.

The Ecotech Aurora Integrating Nephelometer has been used extensively for determining ambient visibility, Koshmeider's Theorem dictates that Visibility = Scat. Coef/3.9 in an ideal world. Real world studies have shown that in urban environments that the following is more likely Visibility = Scat. Coef/3.2. Atmospheric visibility impairment is typical due to aerosols which are the result of urban pollution, dust storms and volcanic activity.

The use of the Aurora Integrating Nephelometer provides an excellent tool for quantifying ambient visibility. It can also be used for providing a very good measure of ambient PM_2.5 concentrations that provide the greatest contribution to ambient visibility impairment.