Transcript Bio112-EcologicalFootprint - University of San Diego Home Pages

What are ecological footprints?
• Ecological footprints measure the extent to
which humans are using the Earth’s
bioproductive capacity
• Units are global hectares
– A hectare of land with “average bio-productive
capacity (for agriculture, forest, nutrient cycling,
energy production, etc.)
– A hectare = 2.5 acres
(1 acre is about a football field between the 5 yard lines)
(1 hectare is 2 complete football fields with endzones)
Ecological Footprint
From Living Planet Report 2008, World Wildlife Fund, 2008.
Ecological footprints measure Earth’s
carrying capacity for humans
• In 2010, the biosphere had about 11.5 billion hectares
of biologically productive surface (about 1/4 of the
total planet)
– 2 billion ha of ocean (the continental shelves)
– 9.5 billion ha of land
• Current estimates indicate that humans are overshooting the Earth’s carrying capacity by 25-50%
– To sustain the current carrying capacity, we could need
11/2 Earths!
– But, population growth and increasing development
means that we are increasing our use of Earth’s
carrying-capacity (bio-capacity)
From Living Planet Report 2008, World Wildlife Fund, 2008.
With respect to sustainability of the human endeavor,
population growth rate and population size are only
part of the picture: per capita consumption is the other
Developed countries
have very large
ecological footprints
Ecological Footprints (Hectares per person)
Ecological Footprint by Region
From Living Planet Report 2008, World Wildlife Fund, 2008.
United States Ecological Footprint By
Component
Biocapacity varies somewhat over time because of
technology, agricultural practices (such as fertilizer use
and irrigation), ecosystem degradation
Mexico’s Footprint by Component
Mexico
• Mexico has moved from using only 1/3 of its biocapacity
in 1961 to nearly 1 ½ times its own biocapacity in 2002
Calculate your own ecological footprint
(Can you realistically reduce your footprint to 1 planet?)
So, where do we stand?
• There are 11.5 billion hectares of bio-productive
land, and it is declining
• There are about 7 billion people, and increasing at
about 1% per year
• There are currently 1 2/3 hectares per person, and
most ecologists believe this is insufficient to support
a significant quality of life for the average person on
Earth
• If we continue down the path we are on, there will be
less than 1 hectare per person by 2050
Sustainability ?
From Living Planet Report 2008, World Wildlife Fund, 2008.
Envisioning Solutions
• Former president Bill Clinton has argued that
combating climate change doesn’t have to mean
economic hardship (Clinton Initiative Topic)
• It could be the biggest development stimulus since
World War II, creating millions of jobs and saving
trillions of dollars in foreign fuel imports
• What are some of the strategies we have available?
9-20
Controlling Emissions is Cheap
Compared to Climate Change
• A 2010 study by the Pew Trust estimates the cost of lost
ecological services by 2100
• Costs included factors such as lost agricultural
productivity from drought, damage to infrastructure from
flooding and storms, lost biological productivity, health
costs from heat stress, and lost water supplies
• The Pew report found that climate change is likely to cost
between $5 trillion and $90 trillion by 2100
• The Stern Review (2006) estimates a cost of only about 1%
of global GDP to avoid the worst impacts of climate change
There Are Many Ways We Can Control
Greenhouse Emissions
• We can reduce dependence on coal, which produces
more CO2 per energy unit than any other fuel
• We could institute fees for selling fossil fuels–these would
help fossil fuel prices represent their many hidden costs
• We can invest in new technologies and energy efficiency
• We can institute emissions trading, by instituting a legal
cap on emissions, then allowing companies to buy and
sell shares of that total cap (California’s AB-32 does
this)
A Wedge Approach Involves Dissecting
the Problem into Stepwise Solutions
• To avoid a doubling of atmospheric CO2 we need to
reduce our annual carbon emissions by about 7
billion tons (=7 gigatons or GT) by 2060
• Scientists have divided these emissions into 14
“wedges”, each of which represents 1 GT of
carbon emissions avoided in the year 2060
Local Initiatives Are Effective
• California has greatly reduced Carbon emisions by
switching all coal burning power plants to natural gas
(decreased CO2 by 30%) & switching to green energy
production
• New Zealand Prime Minister Helen Clark pledged that
her country will be the first to be “carbon neutral”
• Germany has reduced its CO2 emissions at least 10
percent by switching from coal to gas and by
encouraging energy efficiency throughout society
• Denmark now gets 20% of its electricity from windmills
California: A long history of investing in
clean power and energy efficiency
1974
2008
California is a model for efficiency
Per Capita Electricity Sales (not including self-generation)
United States
∆(2005)
kWh/person
= 4,000kWh/yr
= $400/capita
California
Energy Efficiency Strategies
• Flattening out the curve – yesterday
– Decouple sales from revenues– eliminate disincentive
– Set and strengthen building and appliance standards
– Invest in utility energy efficiency programs
• Bending the curve downward– tomorrow
– Strengthen incentives– “Decoupling Plus”
– Set long term goals to achieve durable, broad-based
reductions
– Enhance strategic planning: work backwards from goals
– Improve branding, messaging and marketing
– Invest in workforce and research and development
Wedge Analysis
• Accomplishing just half of these wedges could level off our
emissions. Accomplishing all of them could return to levels well
below those envisioned in the Kyoto protocol
McKinsey, December 2007
U.S. GHG Abatement Mapping Initiative
22 States Committed to Regional Carbon
Markets (w/ an additional 8 “observing”)
Source:
Pew Center
Products and the Environment
• At first glance,
the relationship
between products
& our environment
may seem clear,
BUT….
Let’s consider the simple French fry
• What are its
connects to the
environment?
• What impact does it
have?
How did the fry get to the restaurant?
Suppliers
Truck
Producer
Truck
Processing Plant
Truck
Distribution Center
Truck
Bob’s Burger Shop
http://www.rprogress.org/
What impact did its journey have?
Fossil Fuels
Fossil Fuels
Fertilizers
Suppliers
Machinery
Pesticides
Irrigation
Truck
Seeds
Machinery
Producer
Fossil Fuels
Irrigation
Fossil Fuels
Hydropower
Truck
Hydroelectric dam
Processing Plant
Hydropower
Fossil Fuels
Machinery
Food waste
Truck
Fossil Fuels
Fossil Fuels
Freezer
Distribution Center
Hydroflourocarbons
Freezer
Truck
Bob’s Burger Shop
http://www.rprogress.org/
Animal Feed
Fossil Fuels
Packaging
What impact did these impacts have?
Fossil Fuels
Fossil Fuels
Fertilizers
Runoff
Suppliers
Machinery
Loss of
Biodiversity
Pesticides
Irrigation
Loss of
Biodiversity
Truck
Seeds
Producer
Machinery
Air
Pollution
Fossil Fuels
Hydropower
Hydroelectric dam
Truck
Processing Plant
Hydropower
Fossil Fuels
Irrigation
Fossil Fuels
Air
Pollution
Machinery
Food waste
Truck
Fossil Fuels
Fossil Fuels
Freezer
Distribution Center
Damage
To Ozone
Air
Pollution
Animal Feed
Hydroflourocarbons
Truck
Freezer
Bob’s Burger Shop
http://www.rprogress.org/
Fossil Fuels
Packaging
Solid
Waste
How might all of this affect the
Earth’s systems?
Forests
Fossil Fuels
Fertilizers
Runoff
Fossil Fuels
Suppliers
Loss of
Biodiversity
Seeds
Machinery
Air
Fossil Fuels
Pollution
Hydropower
Hydroelectric dam
Truck
Producer
Truck
Processing Plant
Hydropower
Air
Pollution
Machinery
Loss of
Biodiversity
Pesticides
Irrigation
Forests
River
Fossil Fuels
Irrigation
Fossil Fuels
Cropland
Air
Pollution
Machinery
Forests
Food waste
Truck
Fossil Fuels
Fossil Fuels
Freezer
Distribution Center
Damage
To Ozone
Hydroflourocarbons
Freezer
Forests
Truck
Bob’s Burger Shop
Animal Feed
Grazing Land
Fossil Fuels
Packaging
Built-up Land
Solid
Waste
Built-up Land
http://www.rprogress.org/
We’ve considered only the potato
• Consider all the other
parts of your meal
– the other foods
– the utensils
– the napkins
– the condiments
– the drinks…
• There are multiple
environmental impacts
involved in these as well