1. Chapter 16 Global Climate Change
16.1 – Our Dynamic Climate
16.2 – Climate Change
16.3 – Effects of Climate Change
16.4 – Responding to Climate Change

2. 16.1 Our Dynamic Climate Energy From the Sun
Wind Patterns in the Atmosphere
The Oceans and Climate
Other Factors that Affect Climate

3. Energy From the Sun
The sun is the source of the energy that determines weather and climate on Earth.
Energy from the sun is transferred to Earth by means of radiation.
About 30% of incoming radiation is reflected back into space when it strikes land, water or clouds.
The rest of the solar radiation may be absorbed by Earth and the atmosphere and converted to heat.

4. The Greenhouse Effect in the Atmosphere
The greenhouse effect is a natural process in which certain gasses in the atmosphere keep heat near Earth and prevent it from radiating into space.
The gasses that do this are called greenhouse gasses.
The major greenhouse gasses are water vapor (H20) and carbon dioxide (CO2). Other greenhouse gasses include tropospheric ozone (O3), nitrous oxide (N2O), and methane (CH4).

6. Roles of Greenhouse Gasses
Greenhouse gasses absorb heat as it is radiated off of the Earth’s surface. They prevent the heat from radiating into space as quickly as it otherwise would.
Without greenhouse gasses, life on Earth would not be possible because the Earth would be too cold.

7. The Effect of Latitude
Latitude is a measurement of a place’s distance from the equator.
The equator is located at 0° latitude. The degree measure increases as you travel further from the equator
Areas close to the equator are generally warm, and temperatures decrease as you move nearer to the poles.

8. Latitude and Climate
Latitude effects climate because the sun strikes different regions of the Earth at different angles.
Tropical regions tend to be warm year round because the sun’s rays hit the equator most directly.
Temperate zones are areas where you experience seasonal temperature changes.
Seasons change because the angle at which the sun’s rays strike the Earth changes as the Earth orbits the sun on its axis.

10. Sunspot Cycles A sunspot is a dark spot on the surface of the sun.
The more sunspots on the surface of the sun, the more energy the sun gives off.
The number of sunspots rises and falls in cycles that last about 11 years.

11. Wind Patterns in the Atmosphere
Rising warm air and falling cool air in the atmosphere create convection currents. These currents cause winds.
Prevailing winds are formed from the rising warm air near the equator and the sinking cool air near the poles.

12. The Oceans and Climate
Like winds, ocean currents transport heat over long distances.
Warmer, less salty water moves along the surface of the ocean, and colder, saltier water moves deep beneath the ocean’s surface in a pattern called the thermohaline circulation.
This process causes currents such as the Gulf Stream which keeps Europe warmer than it would be otherwise.

13. El Niño and La Niña
El Niño is a change in air pressure, wind patterns, ocean temperature, and ocean circulation in the Pacific Ocean.
During El Niño, equatorial winds weaken, and the surface water in the eastern Pacific becomes warmer than usual.
The pattern known as La Niña is the opposite of El Niño. Temperatures in the Pacific are cooler than average.

14. Other Factors that Affect Climate
Other factors besides the sun, the atmosphere, and the oceans affect climate.
Four of these factors are topography, volcanoes, regional distribution of vegetation, and changes in Earth’s path around the sun.

15. Topography
A region’s topography describes the surface characteristics of the area, including its elevation and features such as mountains, rivers, and lakes.
In general, the greater the altitude, or elevation, the cooler the air temperatures will be.
In general, precipitation falls on the windward side of mountains, which is the side that wind first passes over.
The leeward side of a mountain range, or the downhill side, gets very little precipitation.

17. Other Factors that Affect Climate
Erupting volcanoes expel huge amounts of particles that may block out some of the sun’s light, having a temporary cooling effect.
Plant life can impact climate by promoting rainfall and influencing local concentrations of carbon dioxide.
Minor changes in the Earth’s orbit and tilt of Earth’s axis change the distribution of sunlight that reaches the surface.

18. 16.2 Climate Change Evidence of a Warming Earth
Studying Climate Change
Finding the Cause of Climate Change

19. Evidence of a Warming Earth
When scientists talk about global climate change, they are referring to many climate characteristics, such as temperature, rainfall, wind patterns and storm frequency.
The term global warming refers specifically to an increase in Earth’s average surface temperature.
Global warming is only one aspect of climate change.

20. Global Climate Change
The Intergovernmental Panel on Climate Change (IPCC) notes that global temperature has increased .74°C in the last 100 years, with the most change occurring in the last few decades.
2005 was the warmest year ever recorded.
Complex changes in worldwide precipitation have taken place.

21. Melting Ice and Rising Sea Levels
Throughout the world, most glaciers are shrinking or even disappearing.
Since 1986, an area in Antarctica known as the Larsen Ice Shelf has lost an area more than three times the size of Rhode Island.
Sea levels are rising in many parts of the world.
Expanding sea water (water increases in volume as it becomes warmer) and water from melting ice caps contribute to this issue.

22. Studying Climate Change
Scientists today can collect real-time weather data from all over the globe.
Over many years, this data becomes a record of climate patterns.
Environmental scientists use clues to determine weather patterns from the past.
Proxy indicators are types of indirect evidence that serve as proxies, or substitutes, for direct measurement.
Scientists can get proxy information from ice sheets, sediments, and tree rings.

23. Modeling Climate
Programs that combine what is known about the atmosphere and oceans to simulate, or imitate, climate processes are called climate models.
Climate models use enormous amounts of data and complex mathematical equations.
Global climate models can usually produce reliable predictions.

24. Finding the Cause of Climate Change
In 1958, a scientist named Charles Keeling began collecting data on carbon dioxide levels in the atmosphere.
His data showed that there was a concentration of carbon dioxide of 315 parts per million (ppm).
In contrast, in 2009, the concentration in the same location was 387 ppm.

26. Causes of Greenhouse Gas Increases
The main source of extra carbon dioxide in the atmosphere is the burning of carbon-containing fuels (fossil fuels), such as oil, natural gas, and coal for energy.
Land-use changes, such as the cutting of forests, have also caused an increase in greenhouse gases.

27. 16.3 Effects of Climate Change
Effects on Ecosystems and Organisms
Impact on People Right Now
Future Impact on People

28. Effects on Ecosystems and Organisms
As ecosystems on land become warmer, some organisms have had to shift to places that are cooler in order to survive.
This drives plants and animals toward the poles and up mountains.
Some bird species have changed their migratory patterns and timing.
In the arctic, melting ice is causing problems for polar bears. With less ice, bears can not hunt seals as effectively and many are dying from starvation or exhaustion from swimming long distances between sheets of ice.

29. Effects of a Changing Ocean
The ocean is becoming warmer and is absorbing more carbon dioxide than ever before.
Unusually warm water temperatures are causing harm to coral reefs.
Algae that live symbiotically with coral are dying – a process called coral bleaching, because without the algae, the corals lose their bright colors.
Ocean water is also becoming more acidic as more carbonic acid is created in warmer waters.

30. Impact on People Right Now
Droughts have reduced crop yields in many areas.
The forestry industry has been impacted by an increase of forest fires as climates are warmer and drier.
Huge storms, such as Hurricane Katrina, cause enormous damage with economic consequences.
Extreme heat causes illnesses from heat stroke to cardiac arrest.

32. Future Impact on People
The IPCC report indicates that carbon dioxide in the atmosphere will continue to rise, and so will the temperatures of the atmosphere and ocean.
The ranges of animals that transmit diseases may expand as parts of the world become warmer.
Coastal areas are at risk of serious flooding as sea levels continue to rise.
Fresh water supplies are threatened by encroaching sea water and the melting of glaciers.

33. 16.4 Responding to Climate Change
Use and Production of Electricity
Transportation
Other Approaches to Reducing Greenhouse Gases
Cooperation Among Nations

34. Responding to Climate Change
We can respond to climate change in two basic ways – adaptation and mitigation.
Adaptation involves protecting people from the effects of global warming.
Mitigation consists of reducing greenhouse gas emissions.
In the long term, mitigation is more important because it addresses the causes of global warming.

35. Use and Production of Electricity
Each person on Earth should be trying to reduce their carbon footprint.
A carbon footprint is the amount of carbon dioxide emissions for which an individual or group is responsible.
Electricity generation is the largest source of U.S. greenhouse gas emissions.
Fossil fuel combustion generates about 70% of the electricity in the United States.

36. Efficiency
Efficiency consists of using energy effectively – that is, accomplishing a job using as little energy as possible.
High-efficiency light bulbs and appliances provide a more effective way to use electricity.
Many appliances now earn the Energy Star rating which is endorsed by the Environmental Protection Agency.

37. Conservation Conservation consists of reducing energy use.
Individual people can make choices that reduce the use of electrical appliances and other devices.
Turn things off when not in use.
Wash only full loads of clothes and dishes.
Unplug appliances and chargers when not in use.

38. Alternate Sources of Electricity
There are many sources of energy that do not burn fossil fuels.
Nuclear energy comes from reactions that take place within atoms.
Solar energy comes from the sun.
Wind power depends on wind to create energy.
Hydroelectric power uses the movement of water.
Geothermal energy comes from the heat trapped inside the Earth.

39. Transportation
Transportation is the second largest source of U.S. greenhouse gas emissions.
Technology to improve fuel efficiency is advancing, but without laws to control efficiency, many car makers are not motivated to change their designs.
Hybrid, electric, or biodiesel cars are good alternatives.

40. Other Approaches to Reducing Greenhouse Gases
Careful farming practices, such as the prevention of erosion, help preserve soil’s ability to hold carbon.
Scientists have developed techniques to reduce the greenhouse gases that come from sources such as rice cultivation, livestock and manure.
In a cap-and-trade program, a government puts a limit on the amount of greenhouse gases that can be released by specific industries and power plants.
Industries that release less greenhouse gas than they are allowed can sell their leftover allowances to less efficient companies.

41. Other Approaches to Reducing Greenhouse Gas
A carbon tax is a fee that a government charges polluters for each unit of greenhouse gas the emit providing a financial incentive to reduce emissions.
A carbon offset is a voluntary payment made when one industry or person, instead of reducing its own greenhouse gas emissions, pays another group or person to do so.
Carbon sequestration, or storage, consists of ways of storing carbon that has been captured or removed from power plant emissions.

42. Cooperation Among Nations
The Kyoto Protocol is an international agreement that seeks to limit greenhouse gas emissions.
The protocol is binding, not voluntary.
127 nations have ratified it.
Nations committed to reducing emissions to below the 1990 levels.
THE UNITED STATES DID NOT SIGN THE KYOTO PROTOCOL!