HUMAN IMPACT ON THE ENVIRONMENT Global Warming and Acid Rain

Human Impacts  Global Warming  Acid Rain  Pollution  Deforestation  Eutrophification  Direct Harvesting  Ozone Depletion  Invasive Species  Reduce, Recycle, Reuse  Reducing Emissions  Laws  Planting and Preservation  Endangered Species List  Alternative energy  Using Renewable resources NegativePositive

Global Warming  Global warming is the gradual increase in the temperature of the Earth’s atmosphere over time  Scientists have collected data from different parts of the globe as evidence of global warming  Global warming is though to be caused by a phenomenon called the greenhouse effect  The greenhouse effect is a theory that the more greenhouse gases (carbon dioxide, water vapor, and methane) there are in the atmosphere, the more sunlight and heat gets trapped in it

Global Warming  These greenhouse gases are released by a number of different sources:  Power Plants that burn fossil fuels  Increase in farm animals that release methane gas  Cutting down forests which absorb CO 2  Landfills release methane gas as garbage rots and decomposes  Increase in the human population

Global Warming: The Debate  Earth’s average temperature has risen a little more than one degree in the past century.  Many scientists believe that temperature fluctuations are cyclical and these fluctuations are normal  We do not have enough data over a long enough period of time to determine who is right, so who do we believe?

Global Warming: The Debate  This increase in average temperature has tripled since the industrial revolution  Scientists have also been measuring glaciers and ice on the poles and these seem to be melting.  There is a concern that certain species like the polar bear cannot adapt quick enough to the changing environment  If eventually the polar ice caps melt completely, our beautiful coasts will be sunk (literally)  Changing temperatures leads to increased storms such as cyclones and hurricanes

Global Warming: The Debate  Unfortunately, we have not been taking the Earth’s temperature for thousands of years and cannot tell if this increase is normal  Also, in some areas the temperature is actually decreasing and glaciers are growing.  You might think that since global warming is caused by greenhouse gases the increased temperatures would occur near major cities, but that is not the case either.  So, where is the proof? What do you believe?

Acid Rain  Combustion of fossil fuels as well as some natural events can release sulfur dioxides and nitrogen oxides into the air.  These particles rise into the atmosphere and either fall back down to the earth as acidic dust or mix with water vapor and clouds to form acid rain.  When acid rain falls over a body of water consistently it can lower the pH enough to kill aquatic organisms.  It also interacts with the bedrock and soil releasing dangerous chemicals that can make the water toxic.  After a long period of time the acid will wear away and destroy anything it lands on including trees and buildings