Main topics from lecture 1

What is the ENVIRONMENT that we talk about in this course: those parts of the physical earth that are host to life (biosphere) — interplay of lithosphere (rocks), hydrosphere (water) and atmosphere (gases)
Time scales of earth processes

Geological — billions (age 4.55 Ga) to millions of years
Environmental science — 10,000 to hundreds of years
Human time scales — thousands to single years

Spatial scales: local (forest, lake) to global (atmosphere, oceans to planet earth)
It is wrong to refer to a stable reference state of the pre-anthropogenic condition of nature: the natural world is continuously changing and the earth has evolved through many types of environments. We should not separate earth science and environmental science.
Notion of ‘stewardship of the natural environment’ returned in the 1960’s (astronauts’ pictures of a blue planet rising behind the moon); earlier ideas of Thoreau and Muir
Why do we care about the environment?

Anthropocentric -- self interest and survival instinct
The natural environment has an intrinsic values not easily expressed in $$$

1950’s-1970’s worries about resource depletion and exhaustion (Club of Rome)

1970’s-1980’s concern about local pollution and some global effects (ozone layer)

1990’s-2000 concerns about global ills — climate change, biodiversity. Notion of biodiversity as a resource: medicine, chemicals, important genepool, also intrinsic value.

Tragedy of the Commons: those areas tended by the most people receive the least care
Some major political turning points in Environmental Issues: Montreal Protocol (1987), Earth Summit Rio (1992), Kyoto conference (1997)
Environmental impact (I) depends on the # of people (P) and the impact of each person I = P . T where T is the technology factor that dictates the resource demand and waste flow. To reverse environmental damage, we have to control population growth (education, combat poverty, social structure) whereas in our personal lives we can help with T as well as vote for environmentally sensitive politicians (Think globally, act locally)
Older theories on environmental catastrophes stem e.g., from Malthus (population wild-growth) versus the more optimistic views of the Cornucopians (trusting in ‘persons’ ingenuity to solve problems). Introduction of the concept Carrying Capacity of the world
Sustainable growth: a lifestyle that does not deplete resources nor creates an excessive waste stream (recycle, re-use, conserve); concept that waste is only a symptom not the very cause of environmental neglect, e.g. compare policies of the Greens.