1. Key Themes in Physical Geography July 6 th, 2009

2. The Environmental Problem Human population growth –1 AD 100 million –1960 3 billion –2008 6.6 billion –2040 9 billion Estimates of Earth’s carrying capacity: 2.5 billion to 40 billion Population bomb

3. The Environmental Problem Human population growth has not been steady –African famines Famine is a consequence of overpopulation and exceedence of environmental resources –The Black Death

4. The Environmental Goal Sustainability – refers to resources and their environment – ensuring that future generations have equal opportunity to the resources that our planet offers Sustainable resource harvest – the same quantity of a resource can be harvested each year for an unlimited or specified amount of time without decreasing the ability of the resources to produce the same harvest level Sustainable ecosystem – ecosystem from which we are harvesting a resource that is still able to maintain its essential functions and properties

5. The Environmental Goal Sustainable global economy – the careful management and wise use of the planet and its resources Under present conditions, the global economy is not sustainable Characteristics of a sustainable economy –Populations living in harmony with the natural environment –An energy policy that does not alter the natural environment –A plan for renewable resources –A social, political, and legal system dedicated to sustainability

6. The Environmental Goal To achieve a sustainable global economy: –Develop an effective population-control strategy –Completely restructure our energy programs –Institute economic planning –Implement social, legal, political, and education changes

7. Carrying Capacity Carrying capacity – the maximum number of individuals of a species that can be sustained by an environment without decreasing the capacity of the environment to sustain that same amount in the future Desirable human carrying capacity depends of quality of life

8. Precautionary Principle When there is a threat of serious, perhaps even irreversible, environmental damage, we should not wait for scientific proof before taking precautionary steps to prevent potential harm to the environment