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Environmental Problems
Foundations of Science
Natural Cause: The universe behaves in a predictable way under “rules” that can be determined through observation and experimentation.Uniformity: The “rules” are constant through space and time.
Foundations of Science
Parsimony: All other things being equal, the simplest explanation is the best.Efficient Cause
cause & effect
Objective
Scientific “Method”
ObservationQuestionHypothesizeTest & ObservePublishRepeat (as necessary)
TheorizePublishRepeat (as necessary)
Environmental Science
interdisciplinarya way of looking at things
scientific (& objective)interconnected systemshuman impact vs naturally occurring•attempt to assign “responsibility”
What is the Environment?definitions
circumstances or conditions that surround an organism or group of organismsthe complex of social or cultural conditions that affect an individual or community
for humans - our home - well suited to our existence
natural world• plants• animals• earth• air• water
“man-made”• sociological• scientific• technological
“Tragedy of the Commons”
common propertyusually owned by all (or the government)examples
• air• water• “air waves”• public land
commons are subject to poor useopen, unregulated accessbenefits of use are focusedcosts are widely distributed
Common Property
must be carefully managedmay privatize
cost of use & effects• internalization of costs• laws and taxes
commons (difficult)•sale of public land•sale of right to use
Global Climate ChangeEarth’s climate has been changing for over 4.5 billion yearswide scale of variabilitycauses of variability
Sunphysical Earth life
Research Priorities
What is the scale of the current change?What are the causes of the current warming?What are the effects of human activity?
Tools to Study Global Change
geologic recordhistorical recordreal time observationmathematical modeling
Energy Balancealmost all energy ultimately from sunearth’s energy cycle
incoming energy• reflected 30%• absorbed 70% (visible & IR)
outgoing energy emitted as IR• (as much energy as received)
Earth warmed by energy between absorption and emissionenergy circulated by air and water movement
Earth’s Temperature
atmospheric retention of heat“greenhouse effect”H2O vapor, CO2, CH4, CFC’s
released by natural & human processes
Earth’s Temperature
historicallyover last billion years: warmer with ice agescurrent ice age• 2MYA to present: cooler with
“interglacials”• last glacial advance ended 10,000 yrs
ago• generally warming since
warming rapidly in last 150 years
Earth’s TemperatureCO2 changes
currently: 0.03% of atmosphererecent highs
• “interglacial periods”• 125K yrs ago and now
releasing stored CO2 from rocks & plants• natural• humans
current increase started in 1800's
other “greenhouse” gasseshuman’s have increased release rate
Potential Effects of Global Warming
local climate changemore rainmore violent storms
sea level risechange in ocean circulation
complex response
Current Research On-line
http://www.globalchange.umich.edu/globalchange1/current/lectures/samson/climate_patterns/http://www.giss.nasa.gov/research/http://www.ncdc.noaa.gov/oa/ncdc.htmlhttp://www.mos.org/cst/article/3369/http://www.scotese.com/climate.htmhttp://www.ngdc.noaa.gov/paleo/ei/ei_cover.htmlhttp://www4.nas.edu/onpi/webextra.nsf/web/climate?OpenDocument
More research and advocacy on-line
American Petroleum Institute:http://api-ec.api.org/environ/index.cfmindustry site
Natural Resources Defense Council:http://www.nrdc.org/globalwarming/environmental organization
Global Warming Information Page:http://www.globalwarming.org/“astroturf” site (no direct supporters listed)
Global Warming Early Warning Signs:http://www.climatehotmap.org/“environmentalist” site (supporters listed)
the Global Simulation Workshophttp://www.osearth.com/workshops/commercial “environmentalist” site
worldwide use of energy
overalloil - 36%coal - 26%natural gas - 23%nuclear - 7%biomass – 6%hydro - 2%geothermal & wind - 1%
U.S. consumes ¼ of worlds energy