Introduction to Environmental Science

What is environmental science?

• The study of how humans and other species interact with one another and the nonliving environment.

• How the parts of nature and human societies operate and interact - a study of connections and interactions

• A physical and social science that integrates information from a wide range of disciplines:– biology– chemistry– physics– geology– geography– resource technology and engineering– resource conservation and management– demography, economics, politics, sociology,

psychology and ethics

Current Environmental Problems1. Population growth2. Deforestation3. Global warming4. Ozone loss5. Resource depletion:

– mineral– energy– soil– agricultural land– water

6. Biodiversity7. Pollution

Sustainability

• Sustainability is the ability to maintain a given state for a specified period of time

• sustainable systems function and survive over a specified time

• environmentally sustainable societies manage their economies, population and resource use within the system's (earth's) ability to absorb insults, replenish resources, and sustain life forms

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years8000 6000 4000 2000 2000 2100

Hunting and gathering

Black Death–the Plague

Time

Industrialrevolution

Agricultural revolution

B.C. A.D.

• Current growth rate: exponential growth at a rate of 1.25%

• Rule of 70:

70/ rate of growth =doubling time

Nu

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?Continued growth

Populationstabilization

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Populationcrash

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(10,000 years)

(100,000 years)

(1 million years)

Tool-making revolution

Agricultural revolution

Industrial & information revolutions

Time

Who can explain the difference between exponential and linear growth?

Exponential: a quantity increases at a constant rate per unit of time

(such as our current rate of 1.25% per year)Linear : growth by the same amount over equal time periods

World Population reached

1 billion in 1804

2 billion in 1927 (123 years later)

3 billion in 1960 (33 years later)

4 billion in 1974 (14 years later)

5 billion in 1987 (13 years later)

6 billion in 1999 (12 years later)

World Population May Reach7 billion in 2013 (14 years later)

8 billion in 2028 (15 years later)

9 billion in 2054 (26 years later)

Human disturbance

Tropic of Capricorn

Equator

Predominantly naturalPartially disturbedHuman dominated

AntarcticCircle

Tropic ofCancer

ArcticCircleArcticCircle

Economic Growth

• GNP: gross national product - market value of all goods and services for either domestic or export produced in that year

• per capita GNP (pcGNP) - divide GNP by total population of the country

Increase capacity to produce goods and services for people's final use Usually involves increasing flow (throughput) of energy and natural resources

Measured

Economic Development

• The improvement of living standards by economic growth

Developing / Developed Countries

• Developed countries: defined as highly industrialized with pcGNP > $10,00– 20% of the world's population– 85% of wealth and income– use 88% of natural resources– generate 75% of the world's waste

• Developing countries: rural, agricultural countries with low pcGNP– more than 1 billion people try to live on less

than $1 day– more children increases family's "workforce"– local populations outstrip available resources

GNP per capita, 1998

Low income (Under $1,000)

Middle income ($1,000–$10,000)

High income (Above $10,000)

World total

Developingcountries

Developedcountries

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1950 2000 2050 2100

Year

• Perpetual resources: on a human time scale, is renewed continuously

* solar energy, winds, tides, flowing water

Renewable resources: On a human time scale, can be replenished fairly rapidly

*fresh air, water, soil, plants & animals

• Nonrenewable resources: on a human time scale, is not replaced; present in a fixed quantity in earth’s crust

*coal, oil, natural gas, metals such as iron &

copper, minerals such as phosphates & clay

Environmental WorldviewPlanetary management

*humans are the most important species

*resources will not run out b/c we can develop & find new ones

*potential for economic growth is unlimited

*success depends on our management

Stewardship

*we are the most important species, but that

carries an ethical responsibility

*resources probably won’t run out, but should be

used wisely

*environmentally beneficial forms of development

should be encouraged

*our success depends on how well we manage

our resources

Environmental wisdom

*nature exists for all species

*earth’s resources are limited, should not be wasted, and are not all ours

*earth-sustaining forms of economic growth should be encouraged

*our success depends on our actins & behaving in a sustainable manner

1. Is current society in developed countries sustainable? Developing countries?

2. Is sustainability a reasonable or desirable goal?

Traditionaldecision making

Environmental

Social Economic

Decision making in asustainable society

Social Economic

Environmental

SustainableSolutions