1

Understanding Our Environment

2

Environmental Science

3

4

The Goals of Environmental Science…

How nature works.

How the environment effects us.

How we effect the environment.

How we can live more sustainably without degrading our life-support system.

5

Human Population

• The human race plays a key role in important issues we will be discussing the whole year Population growth Resource use Poverty Loss of biological diversity Pollution Global climate change

6Fig. 1-1, p. 6

IndustrialRevolution

?

Agricultural revolutionHunting andGathering

Billio

ns o

f peo

ple

Time

Black Death—the Plague

The Population Dilemma – exponential growth

7

Resource Use

• Global economic output is a rough measure of human resource use

• More people due to exponential growth and economic growth ↑ resource use

8

Poverty

• 22 fold ↑ in economic growth b/t 1950 and 2004

• 50% of people still trying to survive off < $3/day

• To survive they must deplete and degrade environment

9

Wealth is becoming Wealth is becoming increasingly increasingly concentrated, with concentrated, with the richest 20% the richest 20% receiving most of receiving most of the world's income the world's income (82.7%).(82.7%).

Poverty

10

Loss of Biological Diversity

• Premature extinction of species due to habitat degradation

• 1%/year• IRREVERSIBLE!• i.e. cutting down forests

due to farming and development

11

Pollution

• Pollution- presence of substances at high enough levels to harm living organisms due to: Natural occurrences= biogenic

(volcanic eruptions) Human activities=

anthropogenic (burning fossil fuels, using pesticides, etc.)

• Disrupt support systems of organisms

12

Pollution

• Occurs more in urban areas• Can contaminate area where

produced or be carried away by wind or water

• Factors that determine damage a pollutant can cause: Concentration Persistence Chemical nature Rate of degradation

13

Climate Change

• Population growth, resource use, poverty, and loss of biological diversity contribute to climate change Global warming Cycle continues

14

What the Earth Provides UsSolar Capital/ Energy

• Solar capital- direct sunlight and indirect forms of renewable solar energy

- Provides 99% of the energy used on earth to sustain life.

- Biomass (plant matter) made by plants during photosynthesis using solar energy (i.e. firewood, food, coal)

- Hydropower, windpower, and solar power

15

What the Earth Provides UsNatural Capital

• Natural capital- Earth’s resources and ecological services Air Water Soil Forests Fishery Minerals Natural water and air

purification

16Fig. 1-4, p. 9

+=NATURAL RESOURCES NATURAL SERVICES

NATURAL CAPITAL NATURAL RESOURCES NATURAL SERVICES

Air Air purification

Water purification

Water storage

Soil renewal

Nutrient recycling

Food productionConservation of biodiversity

Wildlife habitatGrassland and forest renewal

Waste treatment

Climate controlPopulation control(species interactions

Pest Control

CAPITAL = +

Water

Soil

Land

Nonrenewable minerals (iron, sand)

Life (Biodiversity)

Renewable energysun, wind, water flows

Nonrenewable energy (fossil fuels, nuclear power)

RESOURCES SERVICES

17

Environmental and Resource ProblemsThe Big Five Causes

• Major causes of problems

1. Population growth2. Wasteful resource use3. Poverty4. Poor environmental accounting5. Ecological and environmental

ignorance

18Fig. 1-3, p. 8

Sound Science

A Path to SustainabilityIndividuals

MatterTrade-OffsSolutionsNatural Capital

DegradationNatural Capital

Sustainability: The Integrative Theme

Living sustainably - satisfying people’s needsneeds of the present, without depleting natural resources to meet the needs needs of future generations

19Fig. 1-18, p. 25

Shifts needed to

bring about

sustainable revolution

20

Is Our Present Course Sustainable?Guidelines for the Earth

• Never leave it worse than you found it

• Take only what you need• Sustain diverse living organisms• Maintains Earth’s capacity for

self-repair • Decrease waste• Decrease pollution• Decrease population

21

Ecological Footprint

• A measure of human demand on earth’s ecosystems Looks at consumption of:

- Energy- Food- Building material- Water- Other resources

22Fig. 1-7c, p. 13

Nu

mb

er o

f E

arth

s

Humanity's Ecological Footprint

Earth’s Ecological Capacity

Year

23Fig. 1-7b, p. 13

Footprint Per Person(hectares per person)

1 hectare=2.47 acres=12,000 yds2

United States 9.7

4.7European Union

1.6China

India

Japan

0.8

4.8

24

Your Ecological Footprint?

• Go to www.myfootprint.org and complete the Ecological Footprint Quiz Print out the last page of the quiz informing

you how many earth’s are needed if everyone lived like you….