Climate change is not the first major global scale environmental problem. Past environmental problems that have been addressed on a national or global scale include the use of DDT (dichloro-diphenyl-trichloroethane) being banned, the hole in the ozone layer and the use of chlorofluorocarbons (CFC), and excessive amounts of lead in the environment. DDT was in the 1940’s the first modern synthetic insecticide and was used to control mosquito borne illness such as malaria. Initially it was wildly successful and its use pervasive. In 1972 however the U.S. EPA banned the future use of DDT because of its negative effects on wildlife and potentially human lives. The discontinued use of DDT was brought about because of increasing evidence that insects were becoming resistant to it and its environmental effects were very toxic. In addition, Rachel Carson’s book
Silent Spring
brought out public concern of the improper use of pesticides and efforts to control this. Several disconcerting fact about DDT include its persistence in the environment, accumulation in fatty tissues and that it can travel long distances in the upper atmosphere. [9]
CFCs are compounds that were once used as refrigerants coolants and aerosol propellants. These compounds were eventually found in the stratosphere where they break down ozone. Stratospheric Ozone is an incredibly important compound that protects the earth from harmful cancer causing ultraviolet-C-radiation. Research found that CFCs were reducing the concentration of ozone above the Antarctic. In 1987 at the Montreal Protocol, 56 countries agreed to cut then phase out CFCs. This is significant because it was an early and successful example of international cooperation on reducing environmental problems.[10]
Lead in the environment is harmful to both children and adults causing lower IQs in children as well as lower learning and memory abilities. In adults lead negatively affects the brain, kidneys and cardiovascular system. Lead however is incredibly useful and is released by many industries including smelting, metal mines, and waste incinerators. Lead however was not always recognized and regulated as a harmful metal. In 1922 lead was introduced to gasoline. Many years later a scientist Clair Patterson concluded from ice core samples in in Greenland that Americans had 100x the natural levels of lead in their blood. Then in 1970 the Clean Air Act required the EPA to lower emissions of harmful pollutants including lead 90% in the next few years. However it was not until 1990 that lead was banned in gasoline and in 2002 lead levels in American children ages 1-5 decreased 80% from 1976 to 1999. [14]
Both of these success stories end with changes to regulation and concerted efforts to work towards fixing an environmental problem. It has been done before and can be done again with humans working together to mitigate climate change through not just policy but engineering solutions. Even now there is a great movement towards renewable energy generation industries. For example in 2010 investments in renewable electricity generation passed fossil fuels and in the US in 2015 of all the new electricity generation 32.8% was from solar and 38.2% from wind. [16] There is good reason to view climate change as a world problem that can be confronted.