Environmental Science

Unit 1 -Environmental Issues, Their

Causes, & Sustainability(STE Chapter 1, pp. 1-16)

Where are we going?

1. Living more sustainably

2. Population growth, economic growth, and sustainable development

3. Resources

4. Pollution

5. Problems: causes and connections

6. Is our present course sustainable?

1.1 Living more sustainably

environment - everything that affects a living organism

ecology - study of the interactions between organisms & environment

environmental science - interdisciplinary study (ecology, biology, chemistry, geology, social science, economics, politics and ethics) of the relationship between humans & their environment.

Natural Capital

The Sun and Earth’s Natural Capital

Renewable Energy Sources (RES)

Solar derived• RES

– solar– wind– waves– hydro– biomass– geothermal– tidal

Question

What is the big difference between solar energy and energy from natural resources?

Question

What does it mean to be sustainable?

Sustainability – ‘Ability of a system to survive and function over time’

Exponential Growth

exponential growth – quantity increases by a fixed

%-age in a given time

e.g. 2x where x = 0, 1, 2, 3, 4, 5, 6, 7, …

Complete the table:

x 2x

0 1

1 2

2 4

3 8

4 16

7 128

World Population Growth

In less than 200 years,

the population went from 1 billion to 6 billion people

Why? 

BIRTH RATE > DEATH RATE

Critical Environmental Problems

• population growth

• increasing resource use

• destruction/degradation of wildlife habitats

• extinction of plants and animals

• poverty

• pollution

Movie

Movie - http://www.youtube.com/watch?v=aTjQO163P2E

Solutions

• management

• planning

• conservation

• education

• life style changes

• new ways of doing things

Views

73% of habitable area of the planet has been disturbed. How much more when the population increases from 6 to 8 billion by 2028?

VIEW 1 - Neo-malthusianism

Held by Environmentalists‘we are living unsustainably’ As the population increases it puts strain on our natural resources  

VIEW 2 – Cornucopian

Held by Economists and business leaders ‘there are no limits to human population growth that cannot be

overcome by human ingenuity and technology’

End

• Review

1.2 Population Growth, Economic Growth, and Sustainable Economic Development

Cultural change

- has given us more energy and

technology to alter our planet

- allowed population expansion

- increased our environmental impact

What is in store for future generations?

Economic Growth

• Economic growth provides people with more goods and services

– Measured in gross domestic product (GDP) and purchasing power parity (PPP)

• Economic development uses economic growth to improve living standards

– The world’s countries economic status (developed vs. developing) are based on their degree of industrialization and GDP-PPP

Global Outlook

Population Increase

developing countries > developed countries

End

• Review

1.3 Resources

Resource – obtained from the environment to meet human demand, e.g. food, water, goods etc

Perpetual resources – renewed continuously, e.g. solar energy

Renewable resources - can be replenished relatively rapidly, e.g. forests, grasslands, animals, water, air, soil

Nonrenewable resources - can be exhausted & not renewed in human time scales, e.g. fossil fuels, metallic minerals, nonmetallic minerals

Renewable vs. Nonrenewable Resources

Renewable vs. Nonrenewable Resources

We can extend the supply of non-renewables: - Reduce Reuse Recycle(requires less water, energy and other resources, produces less pollution)

Ecological Footprint

Ecological footprint – amount of land needed to produce resources and assimilate waste for an average person in a country

Includes Carbon FP, Food FP,Housing FP, Goods + Services FP

What is you EFP?

see CW1: have to convert 1 ha = 2.5 acres

Biologically productive land: 1.9 ha land per person (1 ha = 10,000 m2)

Mean EFP is 2.3 ha per person

Ecological Footprint

Larger for developed countries

e.g. Netherlands EFP is 15x the countries area.

When population reaches 10 billion, 1 ha per person

Example

EF = 9.6 ha/person

Total EF USA = 9.6 ha/person x (300 x 106) people = 3 x 109 ha

(3 billion hectares)

Area Land USA = 9631418 km2

100 ha = 1 km2, so 1 x 107 km2 x 100 ha = 1 x 109 ha

1 km2

Ratio EF USA : Area Land USA

= 3 x 109 ha = 3

1 x 109 ha

How many times the country’s total land area is the combined ecological footprint (EF) of all persons living in the USA?

Ecological Capacity

Humanity’s EFP

Humanity’s ecological footprint has exceeded earths ecological capacity

For US available land is 6.7 ha per person

Where is extra land coming from?

World Consumption

For developed countries to enjoy their standard of living, others must make do with less.

Environmental destruction and pollution do not know political boundaries

How long it will be until we begin to feel the impacts of our actions at home?

Ecological footprint in relation to available ecological capacityCountries indicated by red dots were in an ecological deficit in 1997 when this study was conducted.

End

• Review

Pollution: undesirable change in physical, chemical, or biological characteristics of air, water, soil, or food that can adversely affect humans or other living organisms

Nonpoint Source: dispersed & often difficult to identify sources (e.g., agricultural runoff)

Point Source: single identified sources of pollution (e.g., smoke stack or effluent discharge)

1.4 Pollution

Point and Non-point Sources

Smol, 2002

What Types of Harm do Pollutants Cause?

- disrupts life-support systems- damages health and property- nuisances (Noise and smell)

  

What type of pollutant is CO2?

Severity

Severity - 3 governing factors: 1. Speciation

How active and harmful a pollutant is.e.g. organic or methyl-mercury is highly toxic to humans whilst its elemental form is also toxic, but to a lesser extent

 2. Concentration

Measured in parts per million (ppm) mg/kg g/g 3. Persistence

Degradable (nonpersistent) – may be broken down, e.g. sewageSlowly degradable (persistent) – e.g. pesticides, oil, plasticsNondegradable – e.g. lead, mercury

The dose makes the poison

Dealing with Pollution

Prevention (the three R’s – refuse, reduce, reuse, recycle) or Cleanup?

2 BIG problems with cleanup.

1. With the population increasing this is only a temporary solution, e.g. catalytic converter in cars

2. Removes a pollutant from one environment into another

End

• Review

1.5 Environmental Problems‘World Scientists' Warning to Humanity’ 1,700 of the world leading scientists issued an appeal in 1992 -The Environment is suffering critical stress in the following areas:

Some Major Problems

Tragedy of the Commons

• Problems cannot by solved by technical means

• Problems raised by human population growth and the use of the Earth's common property natural resources

• Examples:

– Depleting biodiversity

– Burning of fossil fuels

– Pollution of waterways and the atmosphere

– Logging of forests

– Overfishing of the oceans

Fresh water?

“If I do not use this resource, someone else will. The little bit I use or pollute is not enough to matter, resources are renewable”

Cartoon

Management solutions:

Use less, restrict access, convert to private ownership

Solutions?

Game

• Tragedy of the Bunnies

http://www.bunnygame.org

Connections

P x A x T = I

developing countries P is high A and T are low

developed countries A and T are high P low

Actually much more complicated than this!

End

• Review

1.6 Is Our Present Course Sustainable? Guidelines for Sustainability

• Leave the earth as good or better than we found it• Take no more than we need• Try not to harm life, air, water, soil• Protect biodiversity• Help maintain Earth's capacity for self repair• Don't use potentially renewable resources faster than they are

replenished• Don't waste resources• Don't release pollutants faster than Earth's natural processes can dilute

or degrade them• Slow the rate of population growth• Reduce poverty

Advocates for environmentally sustainable economic development call for a shift to using economic

rewards to encourage sustainable choices

Quote

What's the use of a house if you don't have a decent planet to put it on?

–– Henry David Thoreau

How do I succeed in this course?

• be an active learner• seek help (quickly) if needed• complete all assignments, discussions and tests on

time