Environmental Science Look at the World’s Use of its Resources
Over time… • Hunter-Gatherers • Obtained food by hunting and gathering plants • Agricultural revolution – 10,000 years ago, started collecting seeds, etc • Industrial Revolution – middle of 1700s • Water/animal muscle – coal and oil
Industrial Revolution • Machinery made farming, work, etc more efficient. • Cheap transportation over great distances • Materials such as plastic, pesticides, and fertilizers developed
Resources • Natural resource – natural material used by humans • Renewable resource – can be replaced quickly with natural processes • Non-renewable resource – forms at a much slower rate (fossil fuels)
“Tragedy of the Commons” • When land was held in common, individuals grazed as many animals as possible • Overgrazing led to destruction of land resources
“Tragedy of the Commons” • “If I don’t use this resource, somebody else will” • When land was enclosed and owned by individuals, people only grazed what they could support.
“Tragedy of the Commons” • Best short-term interest of individual vs. best long-term interest of society • Earth’s Resources = modern “commons”
Population and Consumption • Developed nations • 75 percent of world’s resources, 20% population = more waste • Ecological Footprint – productive area of Earth needed to support one person in a particular country.
Sustainable World • Sustainability - condition in which human needs are met in a way that human population can survive • Today – far from sustainable
Critical Thinking • Research is often used to make political points • Media distorts information • Be prepared to hear many different view points….
Fossil Fuels • Remains of ancient organisms that changed into coal, oil, or natural gas • Supply is limited • Environmental consequences
Fossil Fuel Formation • Coal – plants in swamps hundreds of millions of years ago • Sediments compressed plant remains • Oil/natural gas – decay of tiny marine organisms • compressed and heated
Coal • 57% of electric production in US formed by coal • Obtained by underground mines and/or mountain removal
Drilling • Oil pumped from the ground; crude oil • Fuels, chemicals, plastics – petroleum products • 45% of world’s commercial energy use
Fossil Fuels and the Future • By 2050, world energy demand will double • Oil production peak??