A.P. Environmental Science Introduction Global Environmental Science Picture n Four global trends

A.P. Environmental Science Introduction

Global Environmental Science Picture

Four global trends

Four Global Trends

Population growth and increasing consumption

Degradation of soils Global atmospheric changes Loss of biodiversity

1. Population growth

1. Population growth

reached 6 billion about October 12, 1999

Will reach 7 billion October, 2011 May reach 10 billion by 2050 World POPClock Population Connection

Fig. 1-1, p. 6

IndustrialRevolution

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Agricultural revolutionHunting andGathering

Billio

ns o

f peo

ple

Time

Black Death—the Plague

Fig. 1-12, p. 18

1. Population growth

The United States reached 300 million on October 17, 2006 at 3:46 AM.

http://www.census.gov/population/www/popclockus.html

California now has 38 million, may have 50 million by 2025

Population Growth All people create demands

on the earth Demand tends to increase

with affluence “affluenza”

Question

“ How can Earth support a near doubling of the population and still increase standards of living”

2. Degradation of Soils

2. Degradation of Soils

Fertile soil is the foundation for plant growth and food production

BUT-- soils are being degraded by erosion , overgrazing, development

3. Global Atmospheric Changes

3. Global Atmospheric Changes

Burning fossil fuels ( oil, natural gas , and coal) has caused increases in global carbon dioxide

CO2 blocks infrared radiation and therefore traps heat in the atmospheric

resulting in displacement of plants, rise in sea level, changes in climate and weather

4. Loss of Biodiversity

4. Loss of BiodiversityIncreasing population and increasing consumption are accelerating conversion of forests, grasslands, and wetlands, etc. to agriculture and urban development

Destruction of habitat

= destruction of species

Biodiversity is important Mainstay of crops and medicine

development Critical factor in maintaining

stability of natural systems For aesthetic and moral reasons

Unifying Themes of Environmental Science

3 Unifying Themes

Sustainability Stewardship Sound science

Sustainability Means that a system or process can be

continued indefinitely without depleting resources to keep it going

Harvests cannot exceed reproduction rates

Lead to concept of sustainable development

Stewardship

Stewards are responsible for earth and its population

Concept originated from environmentalism movement

Sound Science Environmental issues are

sometimes embroiled in controversy

One side is science One side are those who

mistrust scientists and their interpretations and motives

Understanding science People need to understand how

science is done Will lead to greater

understanding of the issues Sound science is essential to

helping guide us into the 21st century