1. Natural Climate Changes

2. Climate changes Earth is constantly changing, including the climate.
Natural processes
Human impacts

3. Climate Change Ice Ages-Periods of extensive glacial cover
The last ice age ended about 10,000 years ago (Pleistocene)
Ice ages have occurred due to changes in Earth’s tilt/axis

4. Volcanic eruptions Volcanoes release large amounts of gas and ashes
Clouds can block out the sun’s radiation and cause a cooling of Earth (Year With No Summer)

5. El Niño
El Niño – Is a period where the Eastern Pacific Ocean gets warmer while the Western Pacific gets cooler
Trade winds delivering warm water to the west die down
The Eastern Pacific Ocean will have a pressure decrease  More rainfall
The Western Pacific Ocean will have a pressure increase  Less rainfall

8. La Niña
La Niña – Period where temperatures in the Eastern Pacific Ocean cool down
Caused when Trade Winds strengthen blowing warm water to the west causing cold water to pile up in the East
The Eastern Pacific Ocean will have a pressure increase  Less rainfall
The Western Pacific Ocean will have a pressure decrease  More rainfall

9. Solar Activity
When the sun is most active – contains sunspots (dark spots) on the sun (more solar radiation)
Increase in number of sun spots – temperatures in North America and Europe increase

10. Short Term Changes In Climate
Seasons are short term periods of climate change
Exist because Earth is tilted on its axis
Some areas of the world get more direct heat

11. Causes of Climate Change
Changes in Earth’s Orbit
Every 100,000 years Earth’s orbit becomes more elliptical
Changes in Earth’s Axis-Every 41,000 years Earth’s tilt changes from 22.1 degrees to 24.5 degrees

12. Sea Level Sea level has fluctuated through Earth’s History.
Global Warming activists often point rises in sea level as evidence
However shifts in tectonic plates can cause a rise in sea level