An Inconvenient Truth: A Global Warning

Links for Enrichment and Further Learning

• Wikipedia - Global Warming
• Earth absorbing more heat than it radiates
• Earth's Energy Out of Balance
• Global Warming -- Signed, Sealed and Delivered
• Media goofed on Antarctic data
• US Senator: Global warming reports are just like Nazis and the Third Reich
• Global warming news from Google
• Spencer Weart's Discovery of Global Warming
• NewScientist.com Guide on Global Warming
• Global Change at the National Academies
• Book Review: The Threat to the Planet, by James Hansen
• Daily Ice Maps - University of Bremen, Germany
• Union of Concerned Scientists - Global Warming
• NOAA Visualization Gallery
• Yahoo News Links on Global Warming
• US EPA Global Warming website
• United Nations Environmental Programme
• Climate Choices - California and global warming
• Harvey's Global Warming Links -- very thorough

Data sources for greenhouse gas emissions

International emissions:
http://yosemite.epa.gov/oar/globalwarming.nsf/content/EmissionsInternational.html

National GHG emissions:
http://yosemite.epa.gov/oar/globalwarming.nsf/content/ResourceCenterPublicationsGHGEmissionsUSEmissionsInventory2006.html

State and local emissions:
http://yosemite.epa.gov/OAR/globalwarming.nsf/content/EmissionsLocal.html

Individual GHG emissions:
http://yosemite.epa.gov/oar/globalwarming.nsf/content/emissionsindividual.html

EPA GHG emission calculator:
http://yosemite.epa.gov/OAR/globalwarming.nsf/content/ResourceCenterToolsGHGCalculator.html

EPA Global Warming Site:
http://yosemite.epa.gov/oar/globalwarming.nsf/content/index.html

The Weather Channel’s Planet in Change Curriculum:
http://admin.www.weatherclassroom.com/upload/materials/Planet_in_Change_new.pdf

ClimateCrisis.Net (The companion website to the film: An Inconvenient Truth):
http://www.climatecrisis.net/

U.S. Mayor’s Climate Protection Agreement
http://www.seattle.gov/mayor/climate/default.htm#who

Chicago Climate Exchange
http://www.chicagoclimatex.com

California Air Resource Board
http://www.arb.ca.gov

Student Learning Outcomes. Following successful completion of this lesson, students should be able to:

Study Questions / Quiz Prep. (Consult Required Reading and lecture notes for answers.)

1. CO2 is a greenhouse gas. How does atmospheric CO2 interact with: 1) incoming sunlight; 2) reflected infrared radiation?
2. Describe / explain the “greenhouse effect.”
3. Describe / explain “global warming.”
4. In 1958, Roger Ravelle and Charles Keeling started to systematically measure atmospheric CO2 in Hawaii. Describe the pattern and trend in atmospheric CO2 levels that they soon observed.
5. Why does atmospheric CO2 go up and down each year?
6. Ravelle and others thought that the rapid increase in atmospheric CO2 was important. Why?
7. The global climate system is complex. It is difficult to accurately “take the planet’s temperature.” One alternative technique is to track the growth or shrinkage of glaciers. What has been the result of this technique in the last 100 years?
8. Where is Mount Kilimanjaro?
9. What two main kinds of climate information can be obtained from ice cores?
10. Using ice core data from the last 1000 years, what has been the temperature trend for the northern hemisphere?
11. Using ice core data for the last 650,000 years, what is the pattern of CO2 levels and global temperature?
12. How do recent CO2 levels compare with historic CO2 levels in the last 650,000 years?
13. At current CO2 emission rates, how will CO2 levels of the year 2050 compare with historic CO2 levels of the last 650,000 years?
14. If normal low points in CO2 levels accompanied ice ages in the northern hemisphere, what might global climate be like with unprecedented high levels of CO2?
15. In the years from 1860 to 2005 what year was the hottest? Has there been a hotter year outside this range?
16. Ocean temperatures are rising worldwide. How could warming oceans affect hurricanes?
17. In 2004, hurricane Catarina hit the South Atlantic coast of Brazil. What was unusual about this storm?
18. What year did the USA experience a record-breaking number of tornados?
19. Hurricane Katrina was a category 1 hurricane when it crossed the southern tip of Florida in 2005. Why did it become a category 5 hurricane just before it slammed into New Orleans?
20. What does the insurance industry think about global warming? Skeptical, like the coal and petroleum industries?
21. Warming oceans lead to increased evaporation, cloud formation and rainfall. But if there are more clouds and more rainstorms worldwide, how could there also be more widespread drought?
22. If the atmospheric CO2 levels double, will the USA become wetter or drier?
23. What is happening right now to Arctic sea ice?
24. The number of drowned polar bears is rising. Why?
25. What is the recent trend for the number of days of frozen soil in the Arctic?
26. If sea ice melts, how does this amplify global warming?
27. If the Greenland icecap melts suddenly and completely, large amounts of freshwater will pour into the North Atlantic. How might this influence the operation of the ocean conveyor in the region?
28. How will Europe’s climate change as a result?
29. The example was given about how changes in seasonal timing can cause previously “in-sync” interactions between species to go out-of-sync. How did the timing of the caterpillars and bird hatchlings get out of sync?
30. Why are pine beetles suddenly and rapidly spreading upward to higher elevations and northward to Canadian forests?
31. Recently, Antarctica has lost several large floating ice shelves. What is the main concern about the aftermath of these losses?
32. What has been the recent trend of seasonal ice melt on Greenland?
33. If the Greenland icecap melts, or if large Antarctic icecaps melt, what will happen to densely populated coastal regions like southern Florida, San Francisco Bay anad Beijing?
34. Given the projected trends in human population growth, what are the chances that global warming problems will be solved on their own?
35. Why are we waiting? Are we desperately searching for essential new technologies before we can attack global warming?
36. What is preventing society from solving this problem?
37. What is the Kyoto Protocol?
38. Did the USA sign it?
39. Did the USA ratify it?
40. What percentage of global greenhouse gas emissions come from the USA?
41. What are 10 ways you can take action in your personal life to help slow global warming?

Synthesis (These are not official study questions. But you should try to answer them on your own.)

Presentation

WHAT IS GLOBAL WARMING?

1. Carbon dioxide and other gases warm the surface of the planet naturally by trapping solar heat in the atmosphere. This is a good thing because it keeps our planet habitable. However, by burning fossil fuels such as coal, gas, and oil, and clearing forests we have dramatically increased the amount of carbon dioxide in the Earth’s atmosphere and temperatures are rising.
2. The vast majority of scientists agree that global warming is real, it’s already happening, and that it is the result of our activities and not a natural occurrence.¹ The evidence is overwhelming and undeniable.
3. We’re already seeing changes. Glaciers are melting, plants and animals are being forced from their habitats, and the number of severe storms and droughts is increasing.
4. The number of Category 4 and 5 hurricanes has almost doubled in the last 30 years.²
5. Malaria has spread to higher altitudes in places like the Colombian Andes, 7,000 feet above sea level.³
6. The flow of ice from glaciers in Greenland has more than doubled over the past decade.⁴
7. At least 279 species of plants and animals are already responding to global warming, moving closer to the poles.⁵
8. If the warming continues, we can expect catastrophic consequences. Deaths from global warming will double in just 25 years—to 300,000 people a year.⁶
9. Global sea levels could rise by more than 20 feet with the loss of shelf ice in Greenland and Antarctica, devastating coastal areas worldwide.⁷
10. Heat waves will be more frequent and more intense.
11. Droughts and wildfires will occur more often.
12. The Arctic Ocean could be ice free in summer by 2050.⁸
13. More than a million species worldwide could be driven to extinction by
    2050.⁹

Notes for above list

¹ According to the Intergovernmental Panel on Climate Change (IPCC), this era of global
warming “is unlikely to be entirely natural in origin” and “the balance of evidence suggests a
discernible human influence of the global climate.”
² Emanuel, K. 2005. Increasing destructiveness of tropical cyclones over the past 30 years.
Nature 436: 686-688.
³ World Health Organization
⁴ Krabill, W., E. Hanna, P. Huybrechts, W. Abdalati, J. Cappelen, B. Csatho, E. Frefick, S.
Manizade, C. Martin, J, Sonntag, R. Swift, R. Thomas and J. Yungel. 2004. Greenland Ice
Sheet: Increased coastal thinning. Geophysical Research Letters 31.
⁵ Nature.
⁶ World Health Organization
⁷ Washington Post, “Debate on Climate Shifts to Issue of Irreparable Change,” Juliet
Eilperin, January 29, 2006, Page A1.
⁸ Arctic Climate Impact Assessment. 2004. Impacts of a Warming Arctic. Cambridge, UK:
Cambridge University Press. Also quoted in Time Magazine, Vicious Cycles, Missy Adams,
March 26, 2006.
⁹ Time Magazine, Feeling the Heat, David Bjerklie, March 26, 2006.

Greenhouse effect. Greenhouse gases, like CO2, trap outgoing infrared radiation. The more CO2 in the atmosphere, the more radiation gets trapped, causing the planet to get warmer.
Image source: An Inconvenient Truth.

Factories, power plants and automobiles are the main sources of CO2 emissions in developed countries. Intentional forest fires are the main sources of CO2 in developing countries.
Image source: An Inconvenient Truth.

Scientists started regularly measuring atmospheric CO2 in Hawaii in 1958. The results are disturbing.
Image source: An Inconvenient Truth.

Glacier melt is a proxy for direct temperature measurements. Melting glaciers indicate a warmer environment.
Image source: An Inconvenient Truth.

Image source: An Inconvenient Truth.

Image source: An Inconvenient Truth.

Image source: An Inconvenient Truth.

On the left is a photograph of Muir Glacier taken on August 13, 1941, by glaciologist William O. Field; on the right, a photograph taken from the same vantage on August 31, 2004, by geologist Bruce F. Molnia of the United States Geological Survey (USGS). Image Credit: National Snow and Ice Data Center, W. O. Field, B. F. Molnia. Image sources: An Inconvenient Truth.

An example of recent glacier retreat between the years 1985 and 2003. Easton Glacier on Mount Baker, Cascades, Washington.
Image source: An Inconvenient Truth.

Discovering long-term trends in atmospheric CO₂

Ancient Air is trapped in the ice. Scientists drill for it.

Scientists dig in the ice for clues about the chemical composition of ancient atmospheres. Tiny bubbles in Antarctic ice store remnants of ancient atmospheres. Scientists extract ice cores, determine their age, then crush them in a vacuum. Liberated air from bubbles is sampled for gas composition.
Image sources: Unknown.

Bubbles in a section of ice from an ice core. The bubbles are filled with air from an ancient atmosphere. Scientists crush the ice in a vacuum. The freed air is analyzed for the ancient mix of atmospheric gases.
Image source: Unknown.

National Ice Core Laboratory, University of Nevada, Reno.
Image source: Unknown.

This graph is based on ice core data from glaciers in the northern hemisphere. The record goes back 1000 years. It shows that average temperatures in the northern hemisphere now are rapidly on the rise.
Image source: An Inconvenient Truth.

Ice cores have provided a record of Earth's ancient climates as far back as 650,000 years. Here, the record for atmospheric CO2 (red) and global temperature (blue) is displayed. Notice the synchronous patterns displayed by these two records.
Image source: An Inconvenient Truth.

If modest dips in CO2 are accompanied by ice ages, what environmental change will accompany the huge increase in CO2 happening today?
Image source: An Inconvenient Truth.

Intense heat waves are consistent with the prediction of CO2-induced global warming.
Image source: An Inconvenient Truth.

You may like it hot, but how would you cope with 122 degree weather?
Image source: An Inconvenient Truth.

Hurricane, cyclone and typhoon intensity has been increasing as warmer ocean waters give more energy to storm systems.
Image source: An Inconvenient Truth.

Tornados could become stronger and more frequent.
Image source: An Inconvenient Truth.

Warmer weather cause more evaporation from the sea and from the land. Hotter climates are predicted to make continental interiors drier. Major food producing regions will suffer from unprecedented drought. Food production zones will shift unpredictably.
Image sources: An Inconvenient Truth.

A corn crop destroyed by dry soil and drought.
Image source: An Inconvenient Truth.

Warming is already causing changes in seasonal timing. In the above drawing, hatching chicks normally arrive coincidentally with caterpillars. The parent birds feed the abundant caterpillars to their hatchlings. But in this example caterpillars are arriving earlier -- disrupting the normal timing pattern. With fewer caterpillars around at hatching time, many baby birds will starve.
Image source: An Inconvenient Truth.

Arctic sea ice has gotten significantly thinner since 1970. By mid century, all Arctic ice will melt and disappear during the summer.
Image source: An Inconvenient Truth.

Loss of ice even now is contributing to the surprising increase in the number of drowned polar bears. As ice melts, the swimming distance between the remaining ice islands increases.
Image source: An Inconvenient Truth.

Land-based ice on Greenland is melting at increasing rates. Water from this icemelt flows to the sea and contributes to the problem of rising sea levels.
Image source: An Inconvenient Truth.

Surface melt from the Greenland ice sheet. This is a raging river of fresh water that can undermine the stability of the Greenland ice sheet while it makes its way to the sea.
Image source: An Inconvenient Truth.

The climate of the northern hemisphere is powerfully influenced by the transport of ocean heat. This drawing shows the global pattern of ocean water in a cycle scientists call the "ocean conveyor." Notice that warmth is delivered to Europe via the Gulf stream leg of this conveyor.
Image source: An Inconvenient Truth.

Scientists are worried that if the Greenland icecap melts rapidly, it will deliver a surge of freshwater into the North Atlantic Ocean. This freshwater will shutdown the ocean conveyor in this region, halting the delivery of warmth to Europe, causing icy climates there.
Image source: An Inconvenient Truth.

If large amounts of land-based ice melt on Greenland and / or Antarctica, the ice melt water will flow to the sea, causing sea levels to rise.
Image source: An Inconvenient Truth.

Scientists predict that if the Greenland ice sheet completely melts, sea level will rise by about 20 feet. The photo above shows how such a change will affect Florida. Many other coastal regions of the world will be affected as well -- causing the displacement of billions of people and property losses in the trillions of dollars.
Image source: An Inconvenient Truth.

Human activity on the Earth. White indicates the distribution of cities. Red indicates the distribution of forest fires. Yellow indicates the distribution of flares from natural gas wells. Light blue in the oceans indicates fishing fleet activity. The Earth is big, but humanity has spread its formidable influence over much of its surface.
Image source: An Inconvenient Truth.

The USA is responsible for about 30% of worldwide emissions of CO2 and other greenhouse gases.
Image source: An Inconvenient Truth.

In order to support the current American lifestyle, over five tons of CO2 are emitted into the atmosphere every year for each American. It is about half of that in Japan and Europe.
Image source: An Inconvenient Truth.

The Kyoto Protocol of 1997 was the first international effort to curb greenhouse gas emissions -- but by only modest amounts. See the Wikipedia article here.
Image source: An Inconvenient Truth.

Map of countries that have signed and ratified the Kyoto Protocol (green). Countries that have not ratified the Kyoto Protocol are shown in gold and red.
Image source: An Inconvenient Truth.

Image source: An Inconvenient Truth.

Image source: An Inconvenient Truth.

Want to do something to help stop global warming?

Take Action This link gives you specific information about how to accomplish the suggestions below...

Here are 10 simple things you can do and how much carbon dioxide you’ll save doing them.

1. Change a light

Replacing one regular light bulb with a compact fluorescent light bulb will save 150 pounds of carbon dioxide a year.

2. Drive less

Walk bike, carpool or take mass transit more often. You’ll save one pound of carbon dioxide for every mile you don’t drive!

3. Recycle more

You can save 2,400 pounds of carbon dioxide per year by recycling just half of your household waste.

4. Check your tires

Keeping your tires inflated properly can improve gas mileage by more than 3%.

Every gallon of gasoline saved keeps 20 pounds of carbon dioxide out of the atmosphere!

5. Use less hot water

It takes a lot of energy to heat water. Use less hot water by installing a low flow showerhead

(350 pounds of C02 saved per year) and washing your clothes in cold or warm water (500 pounds saved per year).

6. Avoid products with a lot of packaging

You can save 1,200 pounds of carbon dioxide if you cut down your garbage by 10%.

7. Adjust your thermostat

Moving your thermostat just 2 degrees in winter and up 2 degrees in summer.

You could save about 2.000 pounds of carbon dioxide a year with this simple adjustment.

8. Plant a tree

A single tree will absorb one ton of carbon dioxide over its lifetime.

9. Turn off electronic devices

Simply turning off your television, DVD player, stereo and computer when you’re not using them will save you thousands of pounds of carbon dioxide a year.

10. Talk to your friends about global warming

Global warming is an important environmental matter that deserves to be talked about in social and professional settings alike.