How Many People Can the Earth Support?

Are we growing beyond the Earth’s ability to support us all?

DEF: Carrying Capacity: the maximum number of people the planet can support now, without using up the resources that future generations will need to support themselves

CONSIDER: What is SUSTAINABLE for our growing population, without using resources faster than the Earth can produce them?

Experts disagree about the exact carrying capacity because there is a variety of factors contributing to this calculation:

What kind of resources neededHow much of those resources are

availableDistribution of resources How much of the resources each person

uses

In 2004, Earth’s carrying capacity was estimated from as low as 1 billion to 44 billion people – wow that’s a large range!

What can reduce Earth’s carrying capacity?

Deforestation

Soil erosion

Pollution

Higher levels of consumption per person

What can increase Earth’s carrying capacity? Technology

Use of fertilizers, hybrid seeds, and irrigation to increase food production

Modern transportation

Low cost energy to boost industrial production

Ecological Footprint Because it’s challenging to determine the Earth’s carrying

capacity…

Scientists have developed a method to study impacts of the human population and lifestyle, represented by the individual…

DEF: Ecological Footprint: The area of the Earth’s productive surface that it takes to support that person.

The ingredients? farmland, pasture, fishing grounds, forested area, lakes, rivers, aquifers, energy sources, disposal of waste, homes, highways, hospitals, schools, shopping malls, baseball fields, etc.

How can ecological footprints vary?Based on each person’s lifestyle and resource

consumption

How can you calculate ecological footprint? You can calculate your individual ecological footprint

Experts calculate the average ecological footprint per country (remember- variation within country)

Units? Ecological Footprints are calculated in acres

An acre is 43,560 square feet -- about one football field

2009 Ecological Footprint Statistics:

The United Arab Emirates has the highest Ecological Footprint per capita, 25.4 acres.

The average American has an Ecological Footprint of 22.3 acres

The average European has a Footprint of 11.1 acres, half that of the average American, but still well above both the world average of 6.4 acres and what is available per person.

On the other end of the scale are Sierra Leone, Haiti, and India, with Footprints of less than 2 acres.

Population Growth and Ecological FootprintAs population increases = total human footprint

increases

Population Growth and Developing Countries Population is growing fastest in developing countriesResource Consumption and Developed Countries Resource consumption is the greatest in developed countries

CONCEPT

1

CONCEPT

2

What does this mean?

Resource Consumption and Ecological FootprintAs average level of resource consumption per person increases

= total human footprint increases

PopulationResource

Consumption

Developed Countries

Slower population growth

Greater resource consumption

Developing Countries

Faster population growth

Less resource consumption

What does this mean?

Larger Ecological Footprint

What’s the big deal?

DEF: Ecological Deficit: using resources more quickly than they can be renewed.

This means that we are living unsustainably and borrowing resources from future generations.

Eeek! What should we do about this?

We need to reduce our ecological footprint and explore sustainable options for future generations.

Reducing our Footprint

PopulationStabilizing our population is one way to address and limit our global footprint. As we reduce population growth, we would have more resources available to each person.

TechnologyOur current footprint is plagued by the waste we create,

especially the impact of carbon dioxide emissions. We need to produce energy in nonpolluting, sustainable ways. For example, hybrid cars or solar-generated electricity.

Reducing Resource ConsumptionExamine the details of how you live – what kind of food you eat, what you choose to buy, transportation methods, recreation choices, etc. What positive changes can you and your family make?

What about those living in extreme poverty?

Some people need to desperately increase their consumption of resources.

As of September 2013, 1.2 billion people are living in extreme poverty

The World Bank defines extreme poverty as living on less than $1.25 / day

The amount of people living in extreme has been decreasing from 1.93 billion in 1981, to 1.91 billion in 1990, to 1.2 billion in 2013. (World Bank)

People in extreme poverty need more food, more education, more health care, access to clean water, and more energy resources. After their basic needs have been met, they can start considering making sustainable choices for their future.

What can developing countries do to help those in extreme poverty? Help provide resources and educational

opportunities! Poor people cannot afford sustainable technologies, so other countries must help.

What resources can developed countries share?

We need to join together and shape our future!

The choices we make today will affect future generations. What kinds of choices and goals can you and your family make that will the Earth help maintain its carrying capacity?