Pollution Causing Global Dimming
According to a report in Friday’s edition of the journal Science, skies all over the world are dimming due to increases in airborne pollution over the past 30 years.
The new study compiles satellite and land-based data on global dimming over a longer period than had previously been available.
"Creation of this database is a big step forward for researching long-term changes in air pollution and correlating these with climate change," Kaicun Wang, of the University of Maryland, told the Associated Press.
"And it is the first time we have gotten global long-term aerosol information over land to go with information already available on aerosol measurements over the world’s oceans."
The researchers reported that the dimming is happening all across the world, except in Europe.Â
Recent declines in pollution have resulted in brighter skies there.
Although previous studies have been inconclusive, researchers believe aerosols can affect weather and climate. Aerosols are capable of absorbing solar energy, and reflecting sunlight back into space.
Some have suggested releasing “sunshade” particles to reduce the amount of sunlight that can be absorbed by greenhouse gases, thus reducing global warming.
Scientists at the National Oceanic and Atmospheric Administration are warning that this idea would also reduce energy production from solar energy power plants.
According to Daniel Murphy, of the NOAA’s Earth System Research Laboratory, particles in the atmosphere also scatter light. This diffused light cannot be used by solar energy systems to produce electricity.
Solar panels that are commonly seen on household roofs, called photovoltaic and hot water panels, use both diffused and direct sunlight, so they would be less affected by a “sunshade” proposal.