What is a La Nina?
When surface waters in the eastern Pacific are colder than normal
Will there be an Ice Age again?
Yes
What is an El Nino?
Causes the surface of the ocean in the eastern Pacific to be unusually warm
How has the atmosphere’s temperature changed over the last 120 years?
risen by about 0.5 degrees Celsius
How often does an El Nino or La Nina happen?
Every 2 to 7 years
What activities increase carbon dioxide?
The burning of wood, coal, oil, and natural gas
What is the purpose of the Ozone?
The Ozone filters out much of the harmful ultraviolet radiation from the sun
What did scientists realize about the Ozone in the 1970’s?
Chemicals produced by humans have been damaging the ozone layer (hole about the size of Africa)
What are Chloroflurocarbons?
CFCs are chemical compounds that can last for decades and rise all the way to the stratosphere, damaging the Ozones
What objects used CFCs?
CFCs were used in Air conditioners and refrigerators, as cleaners for electronic parts, and in aerosol sprays such as deodorants
Without the ozone layer, what harmful thing can happen to humans?
UV radiation can cause eye damage and several kinds of skin cancer
How did the ozone hole start to shrink?
The United States and many other countries banned most uses of CFCs
What are examples of Greenhouse gases?
carbon dioxide, water vapor, and methane
What is the Greenhouse effect?
Gases in Earth’s atmosphere hold in heat from the sun
Name two ways scientists study climate change.
When did carbon dioxide levels start to increase?
the late 1800s
What is the Greenhouse hypothesis?
Many scientists have hypothesized the human activities that add greenhouse gases to the atmosphere maybe warning Earth’s atmosphere
Explain how tree rings tell us about the climate
the size of the rings tells us how much water the tree got or if there was a fire/lightening
Explain how pollen shows us about climate change
The pollen in lakes shows how old the lake/land its on is
What is an Ice Age?
Huge sheets of ice called glacier cover large parts of Earth’s surface
How does volcanic activity impact the climate?
The ash clouds stay in the sky and block sun’s radiation
How does solar energy impact the climate?
Solar energy decreases in 11 year cycles
How does the movement of continents impact the climate?
the land moves from polar zones toward the equator (or vice versa)
What are the four reasons climate changes over time?
Earth’s Position
Solar Energy
Volcanic Activity
Movement of Continents
What are 3 possible effects of global warming?
1.Fertile field might becomes “dust bowls”
2.Warmer ocean water could increase the strength of hurricanes
3.Melting of glaciers and polar ice caps could also increase sea level