environmental science

ENVIRONMENTAL SCIENCE

Earth Lights from SpaceEarth Lights from Space

Earth’s Systems and Changes

• Earth: A dynamic system

• Four interconnected subsystems: Lithosphere, atmosphere, hydrosphere, and biosphere

• Four subsystems mutually adjust

What is Environmental Science?

• Environmental Science IS NOT Environmentalism

• Environmental Science is an interdisciplinary study of connections and is based on SCIENTIFIC principles

• Environmentalism is a social movement dedicated to protecting the environment (air, water, fauna, flora, etc)

Earth

• Earth: geospatially isolated in the universe• Population explosion: exponential growth• Facing limited resources: energy, soil, fresh

water, forests, ocean fisheries, rangelands• Global environment: conflicts and integrated

resolutions• Lessons from Easter Island: aware of limited

resources and needs for sustainable global economy

Environmental Sciences

• Environment: A complex system with physical, biological, geological, ecological, and geopolitical aspects.

• Requires multidisciplinary research Environmental geology, environmental chemistry, global climate change, biological diversity and ecosystems, environmental economics, environmental ethics, environmental law, etc.

• Environmental crisis

Population, environmental hazards, resource limitations and contaminations, environment ownership (both in space and over time)

Fundamental Concepts

Population growthSustainabilitySystem and changeHazardous Earth processesScientific knowledge and values

Human Population Growth

Environmental problem• Population “time bomb”:

Exponential growth• Earth’s carrying capacity limited

More resources, more land space, more waste

• Exponential growth• Uneven growth in space and over time• Good news

The rate of increase in population is decreasing

Human Population Growth

Sustainability

• Ability of natural systems (human cultural systems and economies) to adapt and survive to changing environmental conditions indefinitely.

• Interplay between Natural Resources (Materials-renewable, such as soil, water, air/ nonrenewable, such as oil, minerals) and Natural Services (Fnc of nature-nutrient cycling, pest control, ozone protection) to establish equilibrium in Natural Capital

Plant and AnimalBiodiversity

SEPM Photo CD-10, Environmental Science 1, 1997

Sustainability• An evolving concept • Long-term

implications• Requiring careful

resources allocation, large-scale

• Development of new technology for resource use, recycling, and waste disposal

Sustainability

Measuring sustainabilityMeasuring sustainability• Use and consumption of resources

• Replenishment and renewable rates

• Development and improvement of human environment vs. workable environment

• Humans are living unsustainably by wasting, depleting and degrading the Earth’s Natural Capital at an exponentially accelerated rate. (e.g. overgrazing, overfishing)

Consumption ComparisonsConsumption Comparisons

– 18% of the global population living in developed countries consumes 88% of the world’s total resources.

– USA alone accounts for 6% of the global population , but consumes 25% of its energy resources.

– The Developed world produces 75% of all pollution and wastes.

Ecological Footprints

• Resources vs. Reserves

• Renewable vs. Nonrenewable

• Conservation vs. Preservation

• Recycling

• Reuse

Ecological Footprints

• Amount of biological productive land and water needed to supply the people living in a particular area

• In 2006 WWF estimated that humanity’s global ecological footprint exceeded the Earth’s biological capacity by 25%

• The US has the largest ecological footprint• By 2050, humanity will be trying to use

twice as many renewable resources as the Earth can supply

Pollution

• What is pollution?

• Point sources

• Nonpoint sources

• Unwanted effects of pollution

Why Do We Have Environmental Problems?

• Major causes of environmental problems are

• Population growth• Wasteful and unsustainable resource use• Poverty• People with different environmental

worldviews often disagree about the seriousness of environmental problems

Trying to manage nature without knowing enoughabout it

Populationgrowth

Unsustainableresource use

Poverty Excludingenvironmental costs from market prices

SEPM Photo CD-10, Environmental Science 1, 1997

Some Harmful Results of Poverty

Environmental Effects of prosperity

• Harmful effects– High consumption and waste of resources– Advertising – more makes you happy

• Beneficial effects– Concern for environmental quality– Provide money for environmental causes– Reduced population growth

Hazardous Earth Processes

Hazardous Earth processes and risk statistics Hazardous Earth processes and risk statistics for the past two decadesfor the past two decades

• Annual loss of life: About 150,000• Financial loss: >$20 billion• More loss of life from a major natural disaster

in a developing country (2003 Iran quake, ~30,000 people)

• More property damage occurs in a more developed country

Scientific Principles of Sustainabilities

• Relience on Solar Energy

• Biodiversity

• Population Control

• Nutrient Cycling

Population Control

Reliance onSolar Energy

Biodiversity

Nutrient Cycling

Four scientific principles of sustainability

These four interconnected principles of sustainability are derived from learning how nature has sustained a variety of life on the earth for about 3.7 billion years.

• The top left oval shows sunlight stimulating the production of vegetation in the Arctic tundra during its brief summer (solar energy) and the top right oval shows some of the diversity of species found there during the summer (biodiversity).

• The bottom right oval shows Arctic gray wolves stalking a caribou during the long cold winter (population control).

• The bottom left oval shows Arctic gray wolves feeding on their kill. This, plus huge numbers of tiny decomposers that convert dead matter to soil nutrients, recycle all materials needed to support the plant growth shown in the top left and right ovals (nutrient cycling).

Increasing resource use

Sustainability EmphasisCurrent Emphasis

Pollution prevention

Waste prevention

Protecting habitat

Environmental restoration

Less resource waste

Population stabilization

Protecting natural capital

Waste disposal(bury or burn)

Pollution cleanup

Protecting species

Environmentaldegradation

Depleting and degrading natural capital

Population growth

Some shifts involved in bringing about the environmental or sustainability revolution. Question: Which three of these shifts do you think are most important? Why?Task= 4%---Last date for submission-----25-02-2013Basis for project designing