Environmental science

The Great Acceleration

Human impact and major influence on the climate and environment over time

Anthropocene

Geological time scale where humans had their impact

Who wrote Geology of Mankind- The Anthropocene

Paul Crutzen in 2002

What did Paul Crutzen claim

The Holocene Epoch was over and we need a new epoch of human intervention

What is an Epoch

A time period

What is the human population?

8.3 billion

What is the cause of human population growth?

Agricultural revolution

What is the agricultural revolution?

Growing crops and the domestication of animals

What did the industrial revolution do to society?

It shifted like to a society powered by fossil fuels

Most significant human impact on the environment in 1950

The Great Acceleration

What is the Great Acceleration?

A range of socioeconomic variables and environmental indicators that took off after wartime economics, to mass production and industrialization on a grand scale

What does the environment consist of?

Living and non-living things

Environmental science

The study of how the natural world works and how the environment affects us and how we affect it

Goods provided by resources

Food, timber, minerals, etc.

Ecosystem services

Air, water, purification, cycling of nutrients, climate, regulation, pollinations, and waste recycling

Environmental science and natural studies

Natural world

Environmental science and social sciences

Addresses human interactions and institutions

Environmentalism

A social movement dedicated to protecting the natural world from undesirable changes brought by human interactions

Instrumental value

It’s useful to us- Value to further means to an end

Intrinsic value

Inherent value, regardless if it’s useful

Anthropocentrism

A human-centered view that evaluates the costs and benefits of people

Biocentrism (Ethical)

Gives inherent value to both human and non-human life; all living things have inherent value

Ecocentrism (holistic perspective)

Judges actions based on their effects on ecosystems, contains both living and non-living elements and the relationship between them

Exploitation (1600-1780)

Nature is an unprecedented place of natural resources waiting to be explored

Utilitarian

Instrumental value in natural resources

Early urban America: People moving to cities

Generated environmental challenges, infectious diseases, dust storms, water pollution, soot/smoke, noxious odors, overcrowding, etc.

Industrial Revolution Environmental issues

Toxic water pollution, toxic air pollution, food processing/quality, worker exposure, etc.

Preservation

Environment should be protected in a pristine, unaltered state

Who promoted the preservation ethic?

John Muir

Who helped John Muir with helping preserve National Parks?

Teddy Roosevelt

Conservation Ethic

People should use natural resources but use them wisely, not preserve

Who promoted the conservation ethic?

Gifford Pinchot

Conservation Ethic perspective

Anthropocentrism

Preservation Ethic perspective

(Biocentric/Ecocentric perspective)

Utilitarian conservation (Sustainable yeild)

The use of resources within certain biological limits or within annual growth incriments

What does utilitarian conservation prevent?

Overuse

Environmentalism (1960-1970)

A broad social movement that supports life, habitats, and improving natural environment

Land Ethic founder

Aldo Leopold

What did Aldo Leopold embrace?

The government policy of shooting predators to increase population of deer and other game animales

What did Aldo Leopold change his mind about?

He took an ecocentric view, that healthy ecological systems depended on all interacting parts, living and non-living

What does environmentalism do?

It produces laws that protects resources and the environment.

Example of environmentalism

Earth Day

Sustainability and our future

• Living within our planets means,

• Conserving Earth’s resources so our descendants can use them

• Maintaining fully functional ecological systems

Where is most of the population located?

China and India

What is the U.S human population?

343 million

Rate of Natural increase (RNI o r)

Measures the birth rates and death rates, population growth over time

Sample size

Population at the start of time measured

More births than deaths

Increasing population size

More deaths than births

Decreasing population size

Immigration

Individuals entering a population

Emigration

Individuals leaving a population

PGR (Projected Birth Rate)

Both immigration and emigration must be included when calculating PGR

Rate of natural increase and population growth rate

Not the same thing

Doubling time

Amount of time it would take for a population to double in size

Rule of 70 for doubling time

• Percentage PGR/70

• Decimal PGR/0.7

What is a negative growth rate?

Halving rate

Thomas Malthus (1766-1834)

Author of Principle of Population

Exponential growth

The current value is growing. The larger the value is, the faster the population grows

Linear Growth

Steady incline of growth (Food supply)

Malthusian Trap

Agriculture or economic production would eventually be outstripped by growth in population

Biotic Potential

Maximum reproductive capacity of the population if resources are unlimited (J-shaped curve, exponential growth)

Environmental resistance

Restricts an organisms’s biotic potential

Examples of environmental resistance

Decreasing oxygen supply, low food supply, disease, predator, competition, etc.

S-shaped curve (Logistic growth curve)

Carrying capacity = biotic potential + environmental resistance

Carrying capacity

Population that could be sustained in an area over time

Overshoot

Can temporarily exceed carrying capacity

Dieback

Gradual correction or catastrophic correction (population dying)

When did global population peak?

in 1963 at 22%

Regional population growth rate

• Sub-Saharan African: 2%

• Niger, Equatorial Guinea, Uganda: Above 3.3%

Factors at play in growth rate

• Contraceptive

• Culture

• Religious Belief

• Government interference (One child policy)

Total fertility fate

Number of children a woman can potentially have in her reproductive years

Global fertility rate

2.2 per woman

Replacement fertility rate

2.1

85% of global growth

Comes from Sub-Saharan Africa

World population projection

• Demand for water, food, energy, and resources

• Population increase to 10billion in 2100

Demography

The study pf human population

Population Momentum

Country’s birth rate falls but population continues to grow

Demographic Momentum

• Drives population growth

• Age structure of population

Increasing population pyramid

right side up pyramid

Stable population pyramid

square shaped (cone shaped) pyramid

Decreasing population pyramid

Inverted pyramid

Niger

• High birth rate

• Impoverished

• Low life expectancy

Japan

Decline population

U.K. and U.S.

Growing slowly but stable

W fertility rates are decreasing

• Reduced teen pregnancy

• Delayed childbirth

• Lower infant mortality

• Economic development

• Women in the workforce

How to sustain 9-10 billion people

Countries need to use less land

How many people are malnourished

1 in 7 people

Slow population growth

Leads to high purchasing power, greater corruption, etc.

Cropland agriculture

Covers 12% of earths free land

Pastures

Cover 26% of earths free land

Earth terrestrial surface

40% is used for agriculture

Trophic levels

Only 10% moved form organisms when consumed

Eating vegetables/lower on the food chain

Is more energy efficient

Solving food crisis

• Reducing our waste

• Increasing food production without expanding agricultural land

• Reduce loss and waste

• Increase fish supply

Expansion of agriculture onto tropical forests

Scientists agree that it needs to stop

Energy Independence

Goal of lessening our reliance on foreign oil

Fossil fuels - hydrocarbons

Derived from the remains of dead plants and animals that were exposed to heat and pressure within Earth’s crust over hundreds of millions of years

Types of fossil fuels

Coal, oil, and natural gas

Our primary energy source

Fossil fuels

Coal

Used in making electricity and in steel/cement production