Constructing Our Ecological Footprint1,2
Introduction:
Human activities consume resources and produce waste, and as our populations grow and global
consumption increases, it is essential that we measure nature’s capacity to meet these demands. The
Ecological Footprint has emerged as one of the world’s leading measures of human demand on nature.
Simply put, Ecological Footprint Accounting addresses whether the planet is large enough to keep up with
the demands of humanity.
The Footprint represents two sides of a balance sheet. On the asset side, biocapacity represents the planet’s
biologically productive land areas including our forests, pastures, cropland and fisheries. These areas,
especially if left unharvested, can also absorb much of the waste we generate, especially our carbon
emissions.
Biocapacity can then be compared with humanity’s demand on nature: our Ecological Footprint. The
Ecological Footprint represents the productive area required to provide the renewable resources humanity
is using and to absorb its waste. The productive area currently occupied by human infrastructure is also
included in this calculation, since built-up land is not available for resource regeneration.
Conceived in 1990 by Mathis Wackernagel and William Rees at the University of British Columbia, the
Ecological Footprint is now in wide use by scientists, businesses, governments, agencies, individuals, and
institutions working to monitor ecological resource use and advance sustainable development.
The Global Footprint:
Our current global situation: Since the 1970s, humanity has been in ecological overshoot with annual
demand on resources exceeding what Earth can regenerate each year. It now takes the Earth one year and
six months to regenerate what we use in a year. We maintain this overshoot by liquidating the Earth’s
resources. Overshoot is a vastly underestimated threat to human well-being and the health of the planet,
and one that is not adequately addressed.
1
(http://www.footprintnetwork.org/en/index.php/GFN/),
2
(http://www.sustainablescale.org/conceptualframework/understandingscale/measuringscale/ecologicalfootprint.aspx)
One method of measuring the total “footprint” for a designated population’s activities is measured in terms
of ‘global hectares.’ A global hectare (acre) is one hectare (2.47 acres) of biologically productive space
with an annual productivity equal to the world average. Currently, the biosphere has approximately 11.2
billion hectares of biologically productive space corresponding to roughly one quarter of the planet’s
surface. These biologically productive hectares include 2.3 billion hectares of ocean and inland water and
8.8 billion hectares of land. The land space is composed of 1.5 billion hectares of cropland, 3.5 billion
hectares of grazing land, 3.6 billion hectares of forest land, and 0.2 billion hectares of built-up land. These
surfaces represent the sum total of biologically productive hectares we rely on for our survival. They
represent the earth’s natural capital, and their annual yield represents our annual natural capital income.
Humanity's Footprint by the Numbers
2.6 global hectares
The average Ecological Footprint per person worldwide
1.7 global hectares
The amount of productive land and sea area available (biocapacity) in the
world per person in 2010
1.5 years
The amount of time it takes the planet to regenerate humanity’s Footprint
50 percent
The amount by which humanity’s Footprint exceeds the planet's
regenerative capacity
1.5 Earths
The number of planets we would need to regenerate humanity’s current
demand on the planet
3.9 Earths
The number of planets we would need if everyone lived like average
Americans
X 2.5
The size of the global Ecological Footprint in 2010 compared to 1961
one-half
The amount of biocapacity available per person in 2010 compared to 1961
53%
The percentage of humanity's Ecological Footprint which is accounted for
by carbon dioxide emissions in 2010 (its carbon Footprint)
36%
The percentage of humanity's Ecological Footprint which is accounted for
by carbon dioxide emissions in 1961 (its carbon Footprint)
91
The number of countries with a biocapacity deficit, i.e., in which per capita
Ecological Footprint exceeded per capita biocapacity (out of 152 countries
included)
85%
Percentage of world population living in a country running a biocapacity
deficit
1
(http://www.footprintnetwork.org/en/index.php/GFN/),
2
(http://www.sustainablescale.org/conceptualframework/understandingscale/measuringscale/ecologicalfootprint.aspx)
The National Footprint:
The global Ecological Footprint looks at the total amount of global hectares that are required to support a
particular population, regardless of whether those hectares are within the national borders where that
population lives. It does this by considering the net consumption of the population (or activity) of interest,
subtracting the global hectares used for export from those used for imports and production. When this is
applied to individual nations there is consideration variation from highs near 10 hectares per capita for
such countries as the United Arab Emirates, the United States and Kuwait, to lows less than 1 hectare per
capita for such countries as Haiti, Somalia and Afghanistan.
By comparing the Footprint measure with the actual bioproductive capacity of individual nations it is
possible to determine if that country is in an ecological deficit (using more than it has) or has an ecological
reserve. The US, Japan, the UK, and the United Arab Emirates are all in ecological deficit, using more
global hectares than their own land mass provides. Countries with an ecological reserve include Australia,
Mongolia, and Gabon.
Some, but not all, countries can run ecological deficits by appropriating bioproductive hectares from other
countries. However, the global deficit represented by the 20% overshoot cannot be compensated for as there
is only one planet available. These data highlight the intimate connection between ecological sustainability
and just distribution, and the contribution of international trade to inequities in national Footprints.
What is the Human Carrying Capacity of the Earth?
The current human population uses the equivalent of 1.5 planets to provide the resources we use and absorb
our waste. This means it now takes the Earth one year and six months to regenerate what we use in a year.
Moderate UN scenarios suggest that if current population and consumption trends continue, by the 2030s,
we will need the equivalent of two Earths to support us. If all of the world’s 7 billion people consumed as
much as an average American, it would take the resources of over five Earths to sustainably support all of
them.
1
(http://www.footprintnetwork.org/en/index.php/GFN/),
2
(http://www.sustainablescale.org/conceptualframework/understandingscale/measuringscale/ecologicalfootprint.aspx)
Calculating your Ecological Footprint:
For this exercise you and your research team will need to use the following Global Footprint calculator:
http://footprintnetwork.org/en/index.php/GFN/page/calculators/
Take the quiz on the website for the following lifestyles:
a. Your present lifestyle
b. Your predicted lifestyle based upon your own personal and professional goals.
c. Using information from the background provided by this activity and the following resource:
http://www.givewell.org/international/technical/additional/Standard-of-Living#Incomeandselfreportedwellbeing
Using the guidelines provided by GiveWell, construct a lifestyle portfolio for a high school aged
individual living with a Life Satisfaction index of less than 5.5. Using the lifestyle portfolio you and
your team have constructed, determine this person’s Ecological foot print.
d. The human population currently requires 1.5 Earths to support its resource needs. Assuming the
world’s human population remains static, what specific changes in your individual’s lifestyle
portfolio would allow her to reach that 1.5 Earths goal? How many global hectares would be
required to support her life style under the conditions described in your modified lifestyle
portfolio?
1
(http://www.footprintnetwork.org/en/index.php/GFN/),
2
(http://www.sustainablescale.org/conceptualframework/understandingscale/measuringscale/ecologicalfootprint.aspx)
e. When did the human population exceed the Earth’s carrying capacity (1 Earth)? According to the
Background provided with this activity, how many hectares per capita are required to support the
average North American? How many global hectares of land/capita would be required to reduce
the current Human population’s needs to 1 Earth? Using the Ecological Footprint Calculator,
determine what specific changes would you be required to make in your personal lifestyle portfolio
to reach that goal?
f. (Short Essay) What are your reactions to this activity? Is this an issue that requires your personal
attention? Is this an issue that ought to be addressed on a local and national level? What are you
recommendations (provide specific examples)?
1
(http://www.footprintnetwork.org/en/index.php/GFN/),
2
(http://www.sustainablescale.org/conceptualframework/understandingscale/measuringscale/ecologicalfootprint.aspx)