environmental science: earth as a living planet chapter 1

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Environmental Science: Earth as a Living Planet

Environmental Science: Earth as a Living Planet

Chapter 1Chapter 1

Major Themes of Environmental Science

Major Themes of Environmental Science

World Population In A.D. 1- 100 Million people In 1960- 3 Billion people Today- 6.7 Billion people Projected: 10 Billion by 2040 It took human population almost

2000 years to get to 3 billion, only 40+ years to add 3 billion more

World Population In A.D. 1- 100 Million people In 1960- 3 Billion people Today- 6.7 Billion people Projected: 10 Billion by 2040 It took human population almost

2000 years to get to 3 billion, only 40+ years to add 3 billion more

Problem?Problem?

The Earth has not grown any larger and the abundance of its resources has not increased

Can the Earth SUSTAIN all these people?

What is the maximum number of people that Earth can support? (remember: Easter Island)

The Earth has not grown any larger and the abundance of its resources has not increased

Can the Earth SUSTAIN all these people?

What is the maximum number of people that Earth can support? (remember: Easter Island)

World PopulationWorld Population

How many people the Earth can sustain depends on science and values and is also a question about people and nature.

What quality of life are people willing to accept?

The poorer that quality, the greater the number of people that can be squeezed onto the Earth’s surface

How many people the Earth can sustain depends on science and values and is also a question about people and nature.

What quality of life are people willing to accept?

The poorer that quality, the greater the number of people that can be squeezed onto the Earth’s surface

Human Population Growth

Human Population Growth

John Eli Miller Family Of 7 children born to John Miller, 5

survived him Of 63 grandchildren, 61 survived him Of the 341 great-grandchildren (born

to 55 married grandchildren- an average of slightly more than 6 children per parent- 338 survived him)

John Eli Miller Family Of 7 children born to John Miller, 5

survived him Of 63 grandchildren, 61 survived him Of the 341 great-grandchildren (born

to 55 married grandchildren- an average of slightly more than 6 children per parent- 338 survived him)

John Eli Miller FamilyJohn Eli Miller Family

Modern Population Explosion

Modern Population Explosion

Major factors in population: Supply of Food Supply of Clothing Shelter Decreased death rates (medical

improvement) As a result, the human population has

increased greatly, threatening the environment

Major factors in population: Supply of Food Supply of Clothing Shelter Decreased death rates (medical

improvement) As a result, the human population has

increased greatly, threatening the environment

World Population World Population

Consequences of Rapid Population Growth

Consequences of Rapid Population Growth

FAMINE is one of the things that happen when a human population exceeds its environmental resources

In 1970’s, following a drought in the Sahel Region, 500,000 Africans starved to death and several million more were permanently affected by malnutrition

FAMINE is one of the things that happen when a human population exceeds its environmental resources

In 1970’s, following a drought in the Sahel Region, 500,000 Africans starved to death and several million more were permanently affected by malnutrition

FAMINEFAMINE

In 1980’s - In one year during that period, as many as 22 African nations suffered catastrophic food shortages and 150 million Africans faced starvation

There is a continuing food crisis in Southern Africa (Malawi, Zambia and Zimbabwe)

In 1980’s - In one year during that period, as many as 22 African nations suffered catastrophic food shortages and 150 million Africans faced starvation

There is a continuing food crisis in Southern Africa (Malawi, Zambia and Zimbabwe)

Reasons for Famine?Reasons for Famine?

Drought Size of Population affected by

drought- competing for resources Changing climate- partly because of

human activities Poor farming practices- erosion of

soil Deforestation

Drought Size of Population affected by

drought- competing for resources Changing climate- partly because of

human activities Poor farming practices- erosion of

soil Deforestation

We are forced to confront a choiceWe are forced to confront a choice

Which is more important, the survival of people alive today or conservation of the environment, on which future food production and human life depend?

Which is more important, the survival of people alive today or conservation of the environment, on which future food production and human life depend?

An Urban World

An Urban World

With economic development, comes URBANIZATION

Urbanization = people move from farms to cities and then perhaps to suburbs

Cities and towns increase in size

Cities are commonly located near rivers and coastlines

With economic development, comes URBANIZATION

Urbanization = people move from farms to cities and then perhaps to suburbs

Cities and towns increase in size

Cities are commonly located near rivers and coastlines

Destroying WetlandsDestroying Wetlands

Urban sprawl often overtakes good agricultural land of river floodplains as well as coastal wetlands, which are important habitats for many rare and endangered species.

As urban areas expand, wetlands are filled in, forests are cut, and soils covered over with pavement and buildings

Urban sprawl often overtakes good agricultural land of river floodplains as well as coastal wetlands, which are important habitats for many rare and endangered species.

As urban areas expand, wetlands are filled in, forests are cut, and soils covered over with pavement and buildings

Urban SprawlUrban Sprawl

In developed countries, 75% of the population live in urban areas, with 25% in rural areas

In developing countries, only 40% of the people are city dwellers

It is estimated that by 2025 almost two-thirds of the population (5 billion people) will live in cities

In developed countries, 75% of the population live in urban areas, with 25% in rural areas

In developing countries, only 40% of the people are city dwellers

It is estimated that by 2025 almost two-thirds of the population (5 billion people) will live in cities

Largest Cities

Largest Cities

In 1999, Tokyo, Japan was the world’s largest city

In 2015, Tokyo will still be the world’s largest city with an estimated population of 28.9 million

Megacities- at least 8 million people

Increased from 2 (NY and LA) to 23 in 1995

In 1999, Tokyo, Japan was the world’s largest city

In 2015, Tokyo will still be the world’s largest city with an estimated population of 28.9 million

Megacities- at least 8 million people

Increased from 2 (NY and LA) to 23 in 1995

MegacitiesMegacitiesMost Megacities- 17- are in the

developing world It is estimated that by 2015-

the world will have 36 Megacities, 23 of them will be in Asia

Environmental issues have always focused on non-urban issues (wildlife, etc.) but needs to shift to urban issues

Most Megacities- 17- are in the developing world

It is estimated that by 2015- the world will have 36 Megacities, 23 of them will be in Asia

Environmental issues have always focused on non-urban issues (wildlife, etc.) but needs to shift to urban issues

SustainabilitySustainability

What is sustainability? Refers to resources and their

environment

Sustainable Resource Harvest- the same quantity of that resource can be harvested each year for an unlimited or specified length of time without decreasing the ability of that resource to continue to produce the same harvest level

What is sustainability? Refers to resources and their

environment

Sustainable Resource Harvest- the same quantity of that resource can be harvested each year for an unlimited or specified length of time without decreasing the ability of that resource to continue to produce the same harvest level

Sustainable EcosystemSustainable Ecosystem

An ecosystem that is still able to maintain its essential functions and properties even though we are harvesting one of its resources

An ecosystem that is still able to maintain its essential functions and properties even though we are harvesting one of its resources

Sustainable DevelopmentSustainable Development

A society can continue to develop its economy and social interactions and also maintain its environment for an indefinite time

A society can continue to develop its economy and social interactions and also maintain its environment for an indefinite time

Carrying CapacityCarrying Capacity

Related to sustainability The maximum number of

individuals of a species that can be sustained by an environment to sustain that same amount in the future

Question: What is the maximum number of people that the Earth can sustain?

Related to sustainability The maximum number of

individuals of a species that can be sustained by an environment to sustain that same amount in the future

Question: What is the maximum number of people that the Earth can sustain?

People and NaturePeople and Nature

People and nature are intimately integrated- each affects the other.

We depend on nature for our lives

We depend on nature for beauty and recreation

We affect nature

People and nature are intimately integrated- each affects the other.

We depend on nature for our lives

We depend on nature for beauty and recreation

We affect nature

Gaia HypothesisGaia Hypothesis

Originated by British chemist James Lovelock and American biologist Lynn Margulis

Proposes that the environment at a global level has been profoundly changed by life over the history of life on Earth and that these changes have tended to improve the chances for the continuation of life.

Originated by British chemist James Lovelock and American biologist Lynn Margulis

Proposes that the environment at a global level has been profoundly changed by life over the history of life on Earth and that these changes have tended to improve the chances for the continuation of life.

Placing a Value on the Environment

Placing a Value on the Environment

How do we place a value on any aspect of our environment?

The value of the environment is based on eight justifications: aesthetic, creative, recreational, inspirational, moral, cultural, ecological, and utilitarian

How do we place a value on any aspect of our environment?

The value of the environment is based on eight justifications: aesthetic, creative, recreational, inspirational, moral, cultural, ecological, and utilitarian

Utilitarian JustificationUtilitarian Justification

Sees some aspect of the environment as valuable because it benefits individuals economically or is directly necessary to human survival

Example: Mangrove Swamps provide shrimp that are the basis of the livelihood of the fisherman

Sees some aspect of the environment as valuable because it benefits individuals economically or is directly necessary to human survival

Example: Mangrove Swamps provide shrimp that are the basis of the livelihood of the fisherman

Ecological JustificationEcological Justification

An ecosystem is necessary for the survival of some species of interest to us, or that the system itself provides some benefit.

Example: Mangrove Swamps provide habitat for marine fish, and although we do not eat Mangrove Trees, we may eat the fish that depend on them.

An ecosystem is necessary for the survival of some species of interest to us, or that the system itself provides some benefit.

Example: Mangrove Swamps provide habitat for marine fish, and although we do not eat Mangrove Trees, we may eat the fish that depend on them.

Aesthetic JustificationAesthetic Justification

Our appreciation of the beauty of nature

Example: When people grieve following the death of a loved one, they typically seek out places with grass, trees and flowers and thus we decorate our graveyards

Our appreciation of the beauty of nature

Example: When people grieve following the death of a loved one, they typically seek out places with grass, trees and flowers and thus we decorate our graveyards

Recreational JustificationRecreational Justification

People use wilderness for recreation

Example: White water rafting, fishing, and hiking

People use wilderness for recreation

Example: White water rafting, fishing, and hiking

Inspirational JustificationInspirational Justification

Conservation of nature can be based on its benefits to the human spirit

Example: Religious Retreats

Conservation of nature can be based on its benefits to the human spirit

Example: Religious Retreats

Creative JustificationCreative Justification

Nature is an aid to human creativity

Example: Artists, poets and others find a source of their creativity in their contact with nature

Nature is an aid to human creativity

Example: Artists, poets and others find a source of their creativity in their contact with nature

Moral JustificationMoral Justification

Has to do with the belief that various aspects of the environment have a right to exist and that it is our moral obligation to allow them to continue or help them to persist.

Example: Species have a moral right to exist

Has to do with the belief that various aspects of the environment have a right to exist and that it is our moral obligation to allow them to continue or help them to persist.

Example: Species have a moral right to exist

Do Rocks Have Rights? Do Rocks Have Rights?

The United Nations General Assembly World Charter for Nature, signed in 1982, states that species have a moral right to exist.

The United Nations General Assembly World Charter for Nature, signed in 1982, states that species have a moral right to exist.

The Big QuestionThe Big Question

DO we have a moral obligation to future generations? to leave the environment in good condition for our descendants, OR Are we at liberty to use environmental resources to the point of depletion within our own lifetime?

DO we have a moral obligation to future generations? to leave the environment in good condition for our descendants, OR Are we at liberty to use environmental resources to the point of depletion within our own lifetime?

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