“Even more controversial is global warming, which some scientists believe results from the carbon dioxide emissions. The Earth’s average temperature has increased over the past 100 years, but most of the increase occured before 1940. Determining what causes changes in the earth’s temperature and isolating the effect of carbon dioxide from other factors are proving to be difficult.
Equally controversial is the problem of ozone layer depletion. There is no doubt that a hole in the ozone layer exists over Antarctica and that the ozone layer protects us from cancer-causing ultraviolet rays from the sun. But how our industrial activity influences the ozone layer is simply not understood at this time.”
The author also did not place CO2 in the category of air polution.
Can you guess what subject this textbook covers?
The Eighth Edtion of Microeconomics by Michael Parken of the University of Western Ontario.