IB Humans and Global Change

Ecological footprint

The total area of healthy land and water ecosystems needed to provide the resources you use and to absorb wastes you produce

How many times larger is the American ecological footprint compared to the global average?

Three times larger

How much more does an American use resources compared to an English citizen?

Two times larger

How much more does an American use resources compared to a Chinese citizen?

Five times larger

Did ancient humans cut down forests? If so, where?

Ancient humans cut down forest in China, Southeast Asia, and Central and South America. However, this often did not cause deforestation.

Have people living gin the U.S. cut down forests?

Yes, people living in the u.S.have also cut down many forests over the years.

When did resource use dramatically increase

After the Industrial Revolution of the 1800s

What do humans use regularly during this time?

Fossil Fuels

What uses many resources today?

Advance technology and mass production

How much land on Earth have humans altered outside of the polar regions?

3/4

Anthropocene

The period during which human activity has become the major cause go global change

What must scientists do to plan for the future?

Interpret climate change data

How do scientists interpret climate change data?

• This is done by modeling future changes by both human and nonhuman actions

• These models are run by supercomputers

Climate change

• Climate change is defined as measurable long-term changes in averages of temperature,clouds, winds, precipitation, and frequency of extreme weather events

• It is due to a series of human activities (including the release of carbon dioxide) that change the composition of the atmosphere which in turn changes the average climate of a region

Consequences of climate change

• Consequences of climate change include the melting of the polar icecaps and a general warming of the most areas of the planet

• In addition natural phenomena like hurricanes and wildfires are becoming more intense and frequent

Which regions are most influenced by climate change?

The north and south poles

Carbon neutral

Net carbon = 0

What is changing Earth’s atmosphere faster than it has changed over the entire history of life?

Human activity

What do these activities do?

• Other activities release different gases, causing other effects on global systems

• Water is a greenhouse gas

What do scientists attribute climate change to?

The burning of fossil fuels

When di the rate of warming increase?

• The rate of warming has increased since the industrial revolution

• This increase mirrors the increase of CO2 due to the burning of fossil fuel

How do we prove that the CO2 is what is causing the warming?

• Make two glass boxes

  • CO2 in one and none in other

ANOVA

Anova tells you if there is a statistical difference between the groups

How doe she burning of fossil fuels contribute to acid rain?

• The burning of fossil fuels also contributes to acid rain by releasing sulfur dioxide and nitrous oxide into the air

• These gases combine with water to form sulfuric acid and nitric acid in the form of acid rain, fog, and snow

  • Lower pH of soil

  • Damage skin of organisms

How does the

How does carbon dioxide lower pH of the ocean?

• Carbon dioxide also dissolves into the ocean and lowers its pH

  • Carbon dioxide and water combine to make carbonic acid

  • Acid interacts with calcium carbonate

• This makes it harder for shellfish and corals to maintain their shells and skeletons

Ocean acidification

• Power plants burn fossil fuels which releases carbon dioxide into the atmosphere

• Carbon dioxide mixes with water and becomes carbonic acid

• Carbonic acid interacts with the calcium carbonate in the skeleton of coral

• Fish rely on the coral for a habitat → no coral = no fish

Pollution

Any harmful material created by human activity and released into the environment

Common forms of air pollution

1. Smog

   1. comes from automobiles

2. Greenhouse gases

3. Heavy metals

   1. Mercury

4. Aerosols (released under pressure)

   1. Chlorofluorocarbons

Common forms of water pollution

1. Industrial and agricultural chemicals

2. Residential sewage

3. Nonpoint source pollution

Nonpoint source pollution

Cannot be tied to a specific source

Residential sewage

Sewage goes to treatment plant → plant breaks it down → rain will overflow the system → release the sewage into the ocean

Grey water

• You can have grey water collected and use it for gardening

  • Does not contain human waste but has been used in the home

Negative results of excess carbon dioxide

• The atmosphere and oceans are warming

• The ice at the poles is disappearing

• Ocean levels are rising

• More CO2 released → more ocean temp rising → can hold less dissolved gas → more CO2

• This cycle is out of control on venus

  • Almost all CO2 on the planet is gaseous

• Ice is gone so less reflection is occurring → more warming

Additional results of Climate change

• Total precipitation and seasonal distribution of precipitation are changing

• The frequency of extreme weather is increasing

• Examples include: heat waves, droughts, and hurricanes

• Insurance in florida

  • 10 companies → 5 companies

  • Prices increase

Sustainable development

• Sustainable development serves the needs of humans while preserving ecosystem’s resources

• For sustainable development to be viable nonrenewable resources must be avoided

Renewable resources

• Renewable resources are resources used by humans that can be easily replaced

• Examples include solar and wind powered energy