the earth and its natural environments are not unlimited a tiny inhabitable oasis in a sea of...
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The Earth and its natural environments are not unlimited
A tiny inhabitable oasis in a sea of inhospitable space
Environmental scientists examine the physical, chemical, and biological conditions of the environment, human impacts on the natural environment, and the effect of the environment on all organisms.
INTERDISCIPLINARY
Biology Geography OceanographyEcology GIS Engineering Physics Economics Atmospheric ScienceEthics Sociology GeologyAnthropology Computer Science ArchaeologyChemistry Political Science History Biogeochemistry Law Medicine
Humans are merely a part of nature
We depend on ourenvironment for air,water, food and shelter.
We alter our environment intentionally andunintentionally
Humans, like other organisms, requirerenewable natural resources to survive
Renewable and Non-renewable Resources
Problem: Human Population Growth
How much undisturbed mixedgrass prairie is left?
Consider the southern Alberta landscape:
Is there such a thing as a ‘natural’ environment today?
Human Impacts on the Natural Environment
ftp://toms.gsfc.nasa.gov/pub/eptoms/images/global/Y2004/FULLDAY_GLOB.PNG
Persistent Organic Pollutants (eg. PCB’s)
Source: AMAP
Source: Greenpeace
Zebra mussels Purple loosestrife Crested Wheat Grass
Depleted Fish ‘Stocks’
Photo: CBC
Environmentalism•A social, political and ethical movement and lifestyle concerned with protecting the environment and using its resources wisely
•Not all environmentalists are activists
•Not all environmental scientists are environmentalists
Lifestyle choices
Activism
Subsistence increases only in an arithmetical ratio.
An important scientific essay (cited by Darwin)Recommendations interpreted as classist.
An Essay on the Principle of Population Thomas Malthus, 1798
Population, when unchecked, increases in a geometrical ratio.
Silent SpringRachel Carson, 1962
Often cited as the founder of“environmentalism”
•Investigated the deleterious effects of DDT on water courses, wildlife and human beings
•Human beings are merely a part of nature, distinguished by our ability to alter it
•Called on humankind to take on this view of thenatural world
Humanity as Part of Nature:A new way of thinking ?
• Many religions of indigenous peoples are ‘animist’, devoting spirits to animals, plants, rocks and rivers
•Eastern religions (eg. Confucianism) discuss the importance of conservative environmental stewardship
•Human evolutionary theory is based on the assumption that humans are affected by their environments like any other organism
•Humanity/Nature dichotomy (form of dualism) confined mainly to Christianity, Judaism, Islam and Greek philosophy
The Earth – Small and vulnerable?Apollo 8 photograph
Such photos gave a global perspective to a youthful environmental movement
The Population BombPaul R. Ehrlich, 1968 (Stanford)
Malthusian predictions
Human beings were to morbidly exceed Earth’s carrying capacity by the 1970’s
Erroneous assumptions, inaccurate prophesies
More irresponsible ‘solutions’
Raised popular awareness ofa serious issue facing humankind
Thesis: “Freedom in a commons brings ruin to all”(ie., the best strategy for individuals conflicts with the common good.)
Controversial: Argues for controls on environmentally-detrimental aspects of human behaviour, including reproduction
The Tragedy of the CommonsGarrett Hardin, 1968
Image source: Nikiforuk & Hawaleshka, Reader’s Digest, 06/09/04
Access to education, women’s rights and development are now known to be key to controlling population growth
SustainabilityThe ability of an ecosystem to maintain ecological processes and functions, biodiversity and productivity over time (Kauffmann et al. 1994)
Sustainable DevelopmentAn oxymoron? Depends on how ‘development’ is definedDoes it mean ‘growth’ or ‘improvement?’
To meet the needs of today, without foreclosing the achievement of tomorrow’s needs (IUCN et al. 1980)
Improving quality of life without exceeding ecological carrying capacity
Problem: Wealthy nations already overconsume!
Principles of Sustainability
1. Ecological sustainability
Environmental scientists study how ecosystemssupport us and how we can damage them
Carrying Capacity
(i)The capacity of an ecosystem to support healthy organisms while maintaining its productivity, adaptability and capability for renewal.
(ii) The number of people who can be supported bythe environment over time (difficult to calculate).
Ecological Footprint
Based on estimate of amount of land needed to sustainactivities / population
Shrinking globally (now <1.5 ha/person globally)Increasing in Canada/US (now 4.27-5.10 ha/person)
Consumption must be controlled in high-income countriesfor sustainability objectives to be achieved
2. Social Sustainability
Sustainable development initiatives are socially sustainable if they do not exceed a community’s tolerance for change
3. Economic Sustainability
Resources “must be used in ways that do not permanentlydamage the environment and must not impair the replenishment capacity of renewable resources.”(Government of Canada, 1996)
Deep Ecology
Non-human species are as valuable as humans.
The interest of wild nature must sometimes be chosen over human well-being.
Goes further than sustainable development
Ecofeminism and Social Ecology
Domination of nature and of women are systemicallyrelated
Hierarchy and domination must be eliminated from human society to avoid ecological extinction
Gaia Hypothesis
•Holistic, rather than reductionist view of systemsUniverse is a series of interconnected, interacting wholes
•Earth as a single, indivisible, self-regulating process (Gaia; Lovelock 1988)
THE SCIENTIFIC METHOD
Precautionary Principle
In the face of threats of serious or irreversible damage to the environment, “a lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental deterioration.”
Earth Summit, 1992, Rio de JaneiroSigned by Canada
Problems with the Conventional Application of the Scientific Method (Kriegel et al., 2001)
Assumption that phenomena under consideration aredriven primarily by independent action of a few causalfactors
Narrow definition of uncertainty
Lack of sensitivity analysis
Type I, II amd III Error Standards
Disciplinary divisions
TYPE I ERRORTo conclude that a relationship or difference exists, when it truly does not.
TYPE II ERRORFailure to detect a relationship or difference that does exist.Potential 20% error rate, using current conventions !!!
TYPE III ERRORThe scientist receives the ‘right answer to the wrong question.’
READINGS:Chapter 1;Kriebel et al. 2001. The Precautionary Principle in EnvironmentalScience. Environmental Health Perspectives. 109(9)
Grounds for conserving nature
•Utilitarian justification
A healthy environment, ecosystem or the Earth’s biosphere provide individuals with economic benefits or is directly necessary for survival
“I didn’t take the g.d. fish out of the water!!!”Hon. John C. CrosbieFisheries Minister, 1992
1. Overfishing leads to stock decline2. Turned to other sources of revenue
A complex environmental/socio-political issue
Strong Labrador currentcan exacerbate overfishingproblem (water too cold)
High seal populations canreduce cod stocks
Shrimp trawling/dragging damages the ocean floor, destroying fish breeding grounds
•Ecological justification
Even if individuals do not benefit directly, components of the biosphere provide functions necessary for the persistence of life
Eg. Wetland preservation
Wetland complexes filtercontaminants
Promotes health of wildlife and humans, but protection does not always directly benefit individuals
•Developers stand to make millions
•There is a movement to stop them because the moraine serves an important ecological function(acts as water filter)
SOURCE:TORONTO STAR
•Aesthetic Justification
Nature is beautiful and beauty is of profound importance and value to people
Psychological, medical and social benefits of wild spaces
Wilderness as a sacred space
•Environmental Ethics
Moral responsibility to sustain nature for future generations (environmental stewardship)
Land is not an economic commodity to be used and discarded
Examines rights of animals, plants, non-living things and large systems important to our life support
•Moral justificationElements of the environment have a right to exist1982 United Nations World Charter for Nature