Environmental Science

Environmental Science

Environmental Science - is the study of the interaction of humans with the natural environment.

The environment includes all conditions that surround living organisms:

  • Climate
  • Air and Water Quality
  • Soil and Landforms
  • Presence of other living organisms

Environmental Science and the issues that it studies are complex and interdisciplinary.

  • Includes concepts and ideas from multiple fields of study.
  • Decisions have impacts in all these fields of study.

Major Environmental Problems

  1. Resource Depletion - a great deal of resources are needed to support the human population (7 billion).

Renewable resources - can be replenished within a human lifetime.

e.g, Water

Non-renewable resources - is replenished extremely slowly, if at all. These can be used up.

e.g, Coal, Oil, Minerals

  1. Pollution - is a degradation or an undesired change in air, water, and soil that affects the health of living things.

Biodegradable pollution - will break down naturally over time.

Non-Biodegradable pollution - does not break down.

  • pollution , whether in air or water, can move and affect ecosystems far away from the source.
  1. Loss of Biodiversity - The number of species on the Earth is unknown, but estimated to be in the tens of millions.

Biodiversity - is the number of different species present in one specific ecosystem.

Extinction - the complete loss of a species, is a natural event that can be accelerated by human actions.

  • There are five known major extinction events in Earth’s history. The most major extinction, about 65 million years ago, caused 75% of all species to disappear from the Earth. (Believe to be caused by meteor impact).

Background rate - Assuming no catastrophic events occur, extinction normally occurs at a pretty slow rate.

  • Normal background extinction rate for mammals is 1 every 200 years.

Environmental Ethics

Environmental Ethics - is the discipline that studies the moral relationship of human beings to the environment.

Two main categories

  1. Anthropocentrism - literally means “human-centered”.
  • This set of ethics protects and promotes human interests or well-being at the expenses of all other factors.
  • Often places an emphasis on short-term benefits while disregarding long-term consequences.
  1. Ecocentrists - believe that nature deserves to exist for its own sake regardless of degree of usefulness to humans.
  • The preservation of ecosystems or other living things takes priority over human needs.

Modern Environmentalism

  • In 1952, the Cuyahoga river in Ohio caught fire due to all the pollution that had accumulated in it.
  • Rachel Carson published a book in 1962 entitled Silent Spring about the effects of pesticides on large predatory birds, particularly the bald eagle.
  • This began a public awakening to threats of pollution and toxic chemicals to humans as well as species.

Global Environmentalism

  • Increased travel and communication enables people to know about daily events in places unknown in places unknown in previous generations.

Global environmentalism - explores issues and problems over the entire world, not just within the local community.

The Tragedy of the Commons

  • Describes the likeliness of a commons area being exploited for short-term economic gain.

e.g., Atmosphere, and oceans.

  • A great deal of progress has been made since the birth of modern environmentalism, but many debates still rage on.
  • An ecologist named Garrett Hardin wrote an essay called “The Tragedy of the Commons”, describing the source of environmental problems as a conflict:
  • Short-term interest of individuals vs. Long term interest of civilization and the Earth itself.

Commons - is an area that belongs to no individual; it is shared by the entire society.

Economics and Environment

  • Economics has a huge influence in environmental decision-making.
  • One of the most basic principles of economics is Supply and Demand.

(The greater the demand for a limited resource, the higher the price.)

  • Another important economic idea is the cost/benefit analysis.

Cost/Benefit analysis - This questions whether the benefit of doing something justifies the economic cost.

Population and Consumption

  • Developed countries, while smaller in size and growth, consume resources at a greater rate.
  • About 20% of the world’s population uses 75% of its resources.

The Goal: A Sustainable Word

Sustainability - is when human needs are met so that the population can survive indefinitely.

  • Meeting the needs of the present without compromising the ability of future generations to meet their own needs.

The Spaceship Earth Worldview

  • The Earth is a closed system, meaning nothing enters or leaves the Earth in large quantities is heat.
  • Resources are limited, but the population continues to increase.
  • Waste do not go away.

BASIC SCIENCE CONCEPTS

  1. Nature and Organization of Matter

States of Matter - The Earth is one large mixture of gases, liquids and solids.

Atomic Structure - the main atomic constituents are protons, electrons and neutrons. The relationship of every element present in the environment depends on these subatomic particles.

Compounds - Elements are able to combine to form compounds by reacting together.

  • Organic Compounds
  • Chemical Compounds
  • pH Scale

Energy and Energy Flow

Forms of Energy

  • Mechanical
  • Electromagnetic
  • Electrical
  • Chemical and
  • Thermal
  1. Mechanical Energy - Energy due to an object’s motion (kinetic) or position (potential).

Potential Energy - Energy that is stored in an object due to its position or condition.

Kinetic Energy - Energy of motion, observable as the movement of an object or subatomic particle.