the environmental challenges we face · copyright © 2014 john wiley & sons, inc. all rights...

Visualizing Environmental Science

The Environmental

Challenges We FaceChapter 1

Copyright © 2014 John Wiley & Sons, Inc. All rights reserved.

A World in Crisis: Humans are the Most Significant Agent

of Environmental Change• Increasing populations are

overwhelming the Earth’s ability to regenerate

• Humans transform the landscape

• Destroying or altering habitats leads to species extinction

• Profound affect on processes such as nutrient cycles and climate

• In 2009, a total of 5566 species were classified as endangered worldwide

© 2014 John Wiley & Sons, Inc. All rights reserved.

Human Impacts on the Environment: Overpopulation

• Human population exceeded 7 billion in 2011

• Several billion more projected in 21st Century


Human Impacts on the Environment: The Gap Between “Rich” and “Poor”

• Globally, – A condition in which people are unable to meet their basic needs,

earning less than $2/ day

– 3.3 billion people live in poverty

– Poverty associated

• Fertility rates vary: 1.7 in highly developed countries compared to 4.5 in least developed countries– Highly developed countries have complex industrialized bases, low

population growth rate and high per person incomes


Population, Resources, and the Environment

• People in highly developed countries consume more resources per person than people in developing countries

• Nonrenewable resources– Fossil fuels

– Finite supply that took millions of years to form

• Renewable resources– Trees, soil, water

– Potentially replaced by natural processes



• As a rule, developing countries export their natural resources to highly developed countries

– Developed countries already exploited their own resources

• A larger population consumes more resources and causes more environmental damage than a smaller population



• Highly developed nations represent 20% of the world’s population yet generate 75% of world’s pollution and waste, and consume > half of the world’s resources – 86% of the aluminum used

– 76% of timber harvested

– 61% of meat eaten

– 42% fresh water consumed


Environmental Impact: Ecological Footprint

• Ecological footprint: amount of land and water needed to provide energy, housing, transportation per person

• Allotted global footprint 4.3 acres

• Average global footprint 6.7 acres—overshoot!

• How many Earths do we need to support current consumption?


Environmental Impact : IPAT

• Although developing nations have lower individual footprints, because of their large populations, their overall footprint is high

• Mathematical IPAT model to assess human impact on the environment

• Impact = # people X affluence or resources consumed X technology used to obtain and consume resources (I=P x A x T)

• Goal: sustainable consumption© 2014 John Wiley & Sons, Inc. All rights reserved.

Sustainability and the Environment

• Sustainability is the ability to meet current needs without compromising the ability of future generations to meet their needs– Based on several ideas

• Effects of our actions on the environment

• Earth’s resources are finite

• Understanding impacts of consumption

• Shared responsibility for environmental sustainability


Environmental Science

• Interdisciplinary study of humanity’s relationship with other organisms and the physical environment

– Combines information from many fields• biology, geology,

geography, chemistry, economics, agriculture, law, politics, ethics, etc.


Science as Process

• Science is a body of knowledge AND a systematic process

• Science involves data collection and interpretation

• The scientific method is used to understand the principles that govern the operation of the natural world


The Scientific Method

• The way a scientist approaches a problem, by formulating a hypothesis and then testing it


The Importance of Prediction

• Hypotheses based on what is believed to be true and based on prior scientific work

• Try to test one variable at a time and hold other constant

• Experimental group vs. control group

• May lead to a theory, a well-supported explanation


Science is Constantly Evolving

• As new evidence comes to light, conclusions may change

• Scientific goal is to explain events in nature


Handling Environmental Problems


• The ideal approach to systematically addressing environmental problems- Scientific assessment

- Risk analysis

- Public engagement

- Political considerations

- Long-term environmental management

Handling Environmental Problems


the environmental challenges we face · copyright © 2014 john wiley & sons, inc. all rights...

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