1. Changes in Climate
Earth Science
Mr. Barry

2. Ice Ages
Ice Age: period of extensive glacial coverage, producing long-term climatic changes
Average global temperatures decrease by 5˚ C
Last Ice Age ended 10,000 years ago, covered northern USA plus parts of Europe and Asia

3. Short-Term Changes
Seasons: short-term periods of climatic change caused by regular variations in daylight, temperature, and weather patterns
These changes are a result of the amount of solar radiation a location receives
Cause by tilting of the Earth as it revolves around the Sun

4. Short-Term Changes
El Nino: warm ocean current that develops off the western coast of South America that causes short-term climatic changes felt worldwide
Extended periods of rain cause warmer temperatures leading to heavier than usual rainfall and flooding in some areas

5. Natural Changes
Climate changes are natural and have been occurring for many years
Solar Activity: sunspot cycles can cause warmer and colder temperatures on Earth
Earth’s Orbit: the Earth’s orbit goes from circular to elliptical over the course of a 100,000 year cycle

6. Natural Changes
Earth’s Wobble: over a period of 26,000 years Earth wobbles as it rotates. This will eventually lead to a change in Earth’s seasons
Volcanic Activity: large amounts of ash get caught in the atmosphere, blocking the Sun and causing cooler than normal conditions

7. The Greenhouse Effect
Greenhouse Effect: natural heating of Earth’s surface by certain atmospheric gases, which helps keep Earth warm enough to sustain life
This is necessary for life to survive on Earth

8. Greenhouse Effect & Global Warming
An increase in the Greenhouse Effect could lead to temperatures in excess of what we could survive (470+˚ C)
The balance of the gases that cause the Greenhouse Effect (mainly CO2) is vital to regulating Earth’s temperature
Adding to the amount of greenhouse gases in the atmosphere can cause the overall average temperature of the Earth to rise

9. Global Warming
Global Warming: rise in global temperatures due to increases in atmospheric CO2
Deforestation: removal of trees lowers the amount of organisms using CO2 to live, thus increasing the amount in the atmosphere
Burning Fossil Fuels: burning of fossil fuels releases CO2 as a waste product