Bangalore, Among World's Top Polluted Megacities

For those who live below these thick layers and breathe in the particulates, can suffer severe health risk and it is also an environmental hazard.

The countries which have showed a large decrease in aerosol concentration overall are Europe, and Northeast and Central North America.

The cities which have the most fresh and clean environment are Houston which showed 31 percent decrease; Curitiba in Brazil with 26 percent decrease; and Stockholm, capital of Sweden with decrease of 23 percent in pollution.

Prof. Pinhas Alpert led the research of Tel Aviv University's Department of Geophysics and Planetary Sciences to prepare this study. The method applied by the research team is the first of its kind, in preparing the standardaised global testing of pollution levels. It was published in the American Journal of Climate Change.

There are some American cities with increased in level of pollution. It includes Portland with an average 53 percent rise and Seattle with an average increase of 32 percent. This increase has been correlated to the multiple wildfires that have occurred in these regions during the second half of the examined time period.

Also Read: 8 Global Cities with Extreme Climate Risk