Transcript Lec20-HEImpact - Arizona State University

Human Impact on the
Environment
Policy Responses to
Environmental Change
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Problems of controlling environmental
damage
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Jurisdictional limitations
Democracy  hesitation to tackle long-term
problems
Peripheral country leaders already in marginal
standard
Policy Responses to
Environmental Change
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NGOs
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Operate outside the formal political arena
Focus on specific issues and problems
The United Nations Conference on
Environment and Development (UNCED) held
in Rio de Janeiro in 1992
The Global Environment Facility (GEF)
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A joint project of the UN & WB
The GEF functions in a state-based world
Biosphere
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Three interrelated parts:
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Troposphere (lowest atmospheric layer)
Hydrosphere (surface & subsurface water)
Earth’s upper crust (a few thousand feet)
All needed for life, available for life, & all
that ever will be available life
Constantly recycled & renewed in nature
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A “closed” system
Ecosystem Components and
Cycles
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Plants: The Essential Biotic Component
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Photosynthesis and Respiration
Autotrophic
Animals: Mostly consumers
Abiotic (non-living) entities
Plants
Photosynthesis & Respiration
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Photosynthesis:
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Respiration:
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Sort of reverse-photosynthesis
Humans exhale carbon-dioxide
Plants also “exhale” carbon-dioxide
If they’re autotrophic, do plants need us?
Abiotic and Biotic Components
Pre Monsoon 2005
Post Monsoon 2005
Post Monsoon 2006
Energy, Nutrient, and
Food Pathways
A Simple Food Web
Human Impact on Water
Hydrologic Cycle
How can we compensate?
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Modify waterways
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Channelization
Dam construction
Others?
Must be careful with nature…
The Central Arizona Project
Pumping from the Aquifer...
To the Canal...
To Tucson...
Water Quality & Pollution
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When it comes to water, pollution is
relative
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Potable vs. gray water
Not only anthropogenic
Sources of Water Pollution
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Fertilizers
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Produces excess “nutrients”
Creates eutrophication:
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The enrichment of waters by nutrients
When artificial, can have waaaay too many
nutrients
Algae and plants grow more abundant, taking
oxygen out of water
 Less oxygen left for fish
 Affects half of all lakes in NA, Eur, SEAsia; 40% in
SA; 28% in Africa
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Sources of Water Pollution
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Biocides
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Animal waste
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Herbicides & pesticides from farms
Commercial feedlots
Residences
Industry
Mining
Impact on Air & Climate
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Has there EVER been “clean” air?
Pollution takes place in Troposphere
Natural Factors That Affect Air Pollution
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Winds
Local and regional landscapes
Temperature inversion
Sources of Natural Variable
Gases and Materials
Alaskan Wildfires
Anthropogenic Atmospheric
Pollution
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Carbon monoxide
Photochemical smog
Industrial smog and sulfur oxides
Particulates
Acid Rain
Helpful Ozone
Pollution Sources
Photochemical Smog
Air Pollution
The Urban Environment
Urban Heat Island
Ozone
Ozone
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O3: Noxious on surface, necessary in
atmosphere
Layer in Stratosphere protects us from
harmful ultra-violet (UV) rays
Anthropogenic factors are killing the
ozone layer, creating “holes”
Ozone
Ozone Production in the Stratosphere
The Anthropogenic Culprit
Chlorofluorocarbons (CFCs)…
What are We Doing to Help?
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In US: Clean Air Acts
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Globally: conferences held around the
world to study global climate change
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1963, 1965, 1970, 1977, 1990
Geneva in 1990
Kyoto in 1997
Bonn July 2001
Marrakech November 2001
IPCC’s latest results
Impact on Landforms
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Excavation
Dumping
Surface Depressions
Excavation
Close-up of Mine
Dumping
Impacts on Animals
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Total number of
species on Earth
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Uncertain, but we
know of between 1
and 2 million
species
New species,
especially of
insects, are
discovered
regularly
One ecologist’s
estimate
Impacts on Animals
How soon?
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Human impact has
dramatically
increased rates of
extinction over time
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No longer exist!
Many birds and
mammals were/are
hunted for food,
skins, feathers, etc.
Over 480 animal
species have
become extinct in
the last 400 years
Humans Introducing New
Species
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Awwhhh Rats!
New species may cause extinctions
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May carry diseases
Tropical Pacific islands lost ~2000 species
of birds
Policy Responses to
Environmental Change
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Biological diversity
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United Nations Conference on Environment
and Development agreement in the early
1990s
Affirms preservation significance
Struggle to find balance between LDC need &
biodiversity
Solid Waste Disposal
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The United States: Solid Waste Producer &
Consumer
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3.7 pounds of solid waste pppd
Other high-technology countries also
produce large amounts of solid waste
Solid Waste
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Disposal is a key problem
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Poorer countries throw it into open dumps
Vermin and methane gas
 Rain and waste liquids contaminate groundwater
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Sanitary landfills
Number of suitable landfill sites is declining in
the United States
Capacity nearing “full”
 Transport of waste is very expensive
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Solid Waste Disposal in CA
Solid Waste Disposal
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A global problem
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US, EU, & Japan EXPORT waste to Africa,
Middle and South America, and East Asia
Cash for LDCs, but lack proper disposal facilities
Toxic wastes
Radioactive Wastes
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Low level radioactive wastes
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Low radiation output
Produced by industry, hospitals, research facilities
Government-run landfills—in big, yellow barrels
High level radioactive wastes
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Strong radiation output
Produced solely by nuclear power plants and nuclear
weapons factories
Radioactive for 1000’s of years
Stored in remote locations
Transport problems
The Human Impact
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Anthropogenic impact on the environment:
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May be 25 million types of organisms on Earth
Humans are not unique in possessing a
culture: chimpanzees, gorillas, orangutans,
and dolphins have cultures too.
Some biogeographers suggest the next great
extinction may be caused by humans
Reading
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Kareiva et al. 2007. Domesticated Nature:
Shaping Landscapes and Ecosystems for
Human Welfare. Science 316.
Resources
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Video: Macdonough-Sustainability
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.zip file with a video presentation from:
http://www.ted.org
Currently, one of the most famous
Geographers is Jared Diamond.
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Books debunk some cherished misconceptions
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Guns, Germs and Steel and Collapse
For a great overview see this site:
http://www.ucla.edu/spotlight/archive/html_2004_2005/fac0505_jared_diamond.html
The Future