Next homework available in D2L!
03/04

UNIT 2:
Global Warming,
Natural or Man-Made?

Some Data
The average temperature in our planet is increasing,
BUT it has happened before.

W/m 2
Some Data o C
Solar activity has had a strong correlation with
Earth’s temperature, BUT not in present times.

Some Data
CO
2 concentrations in the atmosphere always correlate very strongly with the average temperature,
BUT CO
2 increases tend to lag with respect to
T increases.

Some Data
CO
2 is a minor component of the atmosphere,
BUT is a potent greenhouse gas involved in many natural cycles in our planet.

Mini-Debate
Each team will split into two groups:
One group will support the position that human actions are the main contributing factor to global warming, while the other group will support the position that the cause of global warming is due to natural occurrences.
Use information you learned today in class to support your arguments.
At the end of the debate, take a poll to determine the overall team’s position on this issue.

Effects?
Since the late 1800s, the average temperature of Earth increased 0.4-0.8
o C
(that’s 0.7-1.4
o F)
Global warming is predicted to have a major impact on climate and life on Earth.
Global Climate Change

Climate

Is global warming affecting hurricanes?
In your groups interpret the data provided and answer the questions on the worksheet.
You have 5 minutes

Hurricanes
Sand storms Tornadoes

Scientists predict that if the current rate of global warming continues, the
Arctic could be ice-free in the summer by 2040.
Rising global temperatures speed the melting of glaciers and ice caps
Sea ice helps maintain the cold temperatures of the underlying water.

Ice extent has a strong influence on Earth’s albedo.

Current rise in sea level is 1.8mm per year.

Flooding
•
Sea-level has risen about 130 meters (400 ft) since the peak of the last ice age about 18,000 years ago.
•
50 million people worldwide could become “environmental refugees” by 2010, displaced by rising sea levels, depleted aquifers and intermittent river flooding.

The snow is melting earlier in the year  much longer fire seasons in Arizona.
Warmer temperatures promotes outbreaks of treeeating beetles which help fuel forest fires

Life: Biodiversity

In pairs interpret the graph and answer the questions on the worksheet. Once you are finished compare your data with the rest of your group.
You have 5 minutes

Biodiversity
In general, biodiversity decreases as temperature increases

 Species that cannot adapt go extinct.
 Antarctic penguin populations have shrunk by 33 percent
 In California, shoreline sea life is shifting northward.

Arctic
Two-thirds of the world's polar bear subpopulations will be extinct by mid-century due to Arctic ice cap melting.

Tropics
Habitats drying out.
Tropical forests give off more CO
2 than they take up.
Rise in CO
2 changes composition of the forest .

How do we make decisions?

Risk Assessment
The determination of quantitative or qualitative value of risk related to a concrete situation and a recognized threat.
A tool to help make the best informed decisions by weighing the pros and cons

• Make the best informed decisions
• Understand potential consequences for each scenario
• Awareness of how to prepare for risks
• Realization of costs involved
Example: H1N1 Vaccine

H1N1 Facts
 The H1N1 is a pandemic flu virus.
 The people that should be vaccinated:
Children 6 months to 24 years old, anyone over 50 and pregnant women.
 The vaccine is 92% effective in pregnant women and depending on the person, two shots may be required.
 The vaccine itself is free, but the provider charges an administration fee.
 H1N1 is very contagious!
*Remember that you are a student that has limited time and funds, and go to a school with almost 40,000 students. What could be some of the possible outcomes for either getting or not getting the vaccination?

Climate Change: Risks?
How can you use “Risk Assessment” to make a decision concerning what to support in the debate about Global Climate Change ?
To Keep in mind:
 Average temperatures are actually increasing;
 A majority of scientist think current climate change is human induced. However, there many people that disagree;
 Consequences of global climate change could be devastating;
 Taking action could be very costly, particularly for developing nations.

Global Climate Change:
Risk Assessment
Using your knowledge about global warming, you need to complete a risk assessment which clearly shows the consequences of taking action or not taking action against global warming.
Consider the political, social, economic, and environmental aspects
You have
10 minutes

Global Climate Change:
Risk Assessment
Based on your completed risk assessment, what will you decide and why?
What is the main factor influencing your decision?
How might you follow through with this decision?
You have 3 minutes