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….
Carbon Cycle
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??
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