Chapter 1: Key Themes in Environmental Science

Overview Major Themes of Environmental Science Human Population Growth Sustainability and Carrying Capacity A Global Perspective An Urban World People and Nature Science and Values

Major Themes of Environmental Science Human population has more than doubled in the last 40 years 6.8 billion people alive today This trend indicates 9.4 billion people by 2050 How many people can the Earth sustain? Depends on science and value Also question of people and nature

Major Themes in Environmental Science Six interrelated themes: Human Population Growth Sustainability A Global Perspective An Urbanizing World People and Nature Science and Values

Human Population Growth Rapid Population Growth

Famine and Food Crisis Famine occurs when population exceeds its environmental resources Sahel region of Africa in 1970s ½ million people starved to death Millions affected by malnutrition Emerging global food crisis Due to rise in fuel cost = higher food cost

Underweight children under the age of 5 by region (mostly from low and middle-income countries)

Famine and Food Crisis Food crisis caused by rising food costs

Sustainability and Carrying Capacity What is the maximum number of people the Earth can sustain? Currently we are using resources unsustainably (faster that they can be replenished) Minerals Petroleum Groundwater Land and wildlife

Sustainability Difficult term to define because used in many ways Two formal scientific uses: Sustainability of Resources Sustainability of an Ecosystem Two global economics uses: Sustainable Development Sustainable Growth

Sustainable Global Economy To achieve a Sustainable Global Economy, humans must: Develop an effective population control strategy Restructure the energy program Institute economic planning (taxes to encourage low population and high resource conservation) Implement social, legal, political and educational changes to this end

Moving Toward Sustainability The new paradigm Evolutionary rather than revolutionary Inclusive, not exclusive Proactive, not reactive Attracting, not attacking Assisting the disadvantage, not taking advantage

Carrying Capacity of the Earth Defined as the maximum number of individuals of a species that can be sustained by an environment w/o decreasing the capacity of the environment to sustain that same amount in the future

A Global Perspective The actions of many groups of people at many locations affects the environment of the entire world. Gaia hypothesis James Lovelock and Lynn Margulis Life affects the environment at a global level

An Urban World We are becoming an urban species In developed countries 75% live in urban area Developing countries 40%

An Urban World Megacities Urban areas with more than 2 million inhabitants Increased from 2 in 1950 (NYC and London), to 22 in 2005 By 2015 most megacities will be in Asia

Megacities by 2015

People and Nature We depend on nature directly for Wood, water, air And indirectly for “public services functions”, including: soil to farm land Atmosphere ozone layer to protect us from radiation trees to create oxygen wetlands to filter water

People and Nature New unity: Humanity and the Environment must persist together Success for one involves success for the other

Science and Values We must choose what we want the environment to be Value judgment regarding the world’s human population problem Choice between desire to have large family and the need to limit the human population The more high tech and powerful our civilization, the more knowledge and critical thinking is required

Science and Values Selected Intellectual Standards: Clarity Accuracy Precision Relevance Depth Breadth Logic Significance Fairness

Precautionary Principle 1992 - Rio Earth Summit on Sustainable Development Definition: When there is a great threat of serious environmental damage, we should not wait for scientific proof before taking precautionary steps to prevent potential harm PROACTIVE Tool for environmental management San Francisco uses it

Placing a Value on the Environment The value of the environment based on 8 justifications Inspirational Creative Moral Cultural Utilitarian Ecological Aesthetic Recreational

Placing a Value on the Environment Utilitarian (Materialistic) The environment has value because it benefits individuals economically or is necessary for human survival Ecological Ecosystem is necessary for survival of some species of interest or that the system itself provides benefit.

Placing a Value on the Environment Aesthetic Based on our appreciation of the beauty of nature Recreational Viewing organisms in a natural setting Inspirational Benefit to the inner self Creative Aid to human creativity

Placing a Value on the Environment Moral Belief that various aspects of the environment have the right to exist and it is our obligation to allow them to continue Cultural Different cultures have different values when it comes to the environment

How is the environment valuable to each of you? Inspirational Creative Moral Cultural Think of at least 1 example for each category: Utilitarian Ecological Aesthetic Recreational