Natural Processes that Change Climate Volcanic Eruption Ocean Circulation Solar Activity Earth Motions CO 2 fluctuations Ocean acidification Objective:2.6.2 Explain changes in global climate due to natural processes.

Natural Processes that Change Climate Volcanic Eruptions The presence of volcanic ash, dust, and aerosols in the air increase the amount of solar radiation that is reflected back into space. This causes Earth’s lower atmosphere to cool.

Eruption of the Eyjafjallajökull volcano in Iceland video. Eruption of the Eyjafjallajökull volcano in Iceland video. What are the possible affects on weather in the area?

Natural Processes that Change Climate Ocean Circulations Changes in ocean circulation also can result in short- term climate fluctuation. The sun’s energy & the emission of greenhouse gases into the atmosphere can alter the temperature and circulation patterns of the atmosphere-ocean system. EX: El Niño Example: El Nino

Natural Processes that Change Climate Solar Activity The formation of sunspots appears to correspond with warm periods in Europe and North America. Sunspot link Sunspot link Sunspots are darker, cooler areas on the surface of the sun, in a region called the photosphere. They are caused by interactions with the sun’s magnetic field.

Natural Processes that Change Climate Earth Motions Geographic changes in Earth’s land and water bodies cause changes in climate Changes in the shape of Earth’s orbit and the tilt of Earth’s axis affect global climates.

Natural Processes that Change Climate CO 2 Fluctuations Changes in plant growth rates CO 2 levels fall during the growing season and rise in the winter

Natural Processes that Change Climate Ocean Acidification Decrease in the ocean’s pH levels. CO 2 is absorbed by the ocean and forms carbonic acid. Coral Reefs: High levels of CO 2 negatively affects corals making their shells. 50% of coral reefs have been destroyed Ocean Acidification

Human Impact on Climate Changes The Greenhouse Effect Is a natural warming of both Earth’s lower atmosphere and Earth’s Surface. Major Gases: Water vapor and Carbon dioxide, methane, nitrous oxide Makes life as we know it possible on Earth

Explain the greenhouse effect. Include a diagram which shows the change in wavelength.

Just like a greenhouse, the gases in the atmosphere ---especially CO absorb re-radiated infrared energy.

Name the three primary gases which absorb infrared (IR) energy

Why is the ozone layer important? It protects the Earth from UV which damages crops and causes cancer in humans.

Check for Understanding? 1. Which natural process causes Earth's lower atmosphere to cool? 2. What corresponds with warm periods in Europe and North America? 3. What decreases in the ocean to cause ocean acidification?

Human Impact on Climate Changes The Greenhouse Effect Cont. Humans have added more greenhouse gases to the atmosphere in the past 200 years. Greenhouse Effect clip NASA's link

Human Impact on Climate Changes Global Warming As a result of increases in CO 2 as well as other greenhouse gases, global temperatures have increased. Affects multiple natural events like the weather and melting the polar ice caps.

Human Impact on Climate Changes Global Warming Global Warming clip NASA Global Warming Facts

Check For Understanding 1. Compare and contrast the greenhouse effect and global warming. 2. What is the relationship between burning fossil fuels and climate change? Explain.

Agree or Disagree? 5. ____ There are no processes that can change climate. 6. ____The Greenhouse effect is the natural warming of Earth’s lower atmosphere and surface. 7. ____ Global warming is the result of increased greenhouse gases, like CO2, being released by humans.

El Nino verses La Nina El Ni ñ o Trade winds weaken Warm ocean water replaces offshore cold water near South America Irregular intervals of three to seven years Wetter than average winters in NC La Ni ñ a  Normal conditions between El Nino events  When surface temperatures in the eastern Pacific are colder than average  The southern US is usually warmer and dryer in climate

Explanation of El Nino Another look at El Nino

© Occurs: three to seven years © The warm countercurrents in the Pacific become unusually strong and replace normally cold offshore waters with warm equatorial waters. © Characterized by unusually warm ocean surface temperatures El Nino Southern Oscillation: ENSO

El Niño A warming of the Pacific Ocean. Winters: West = Stormy South = Cold, wet Northeast = warmer El Niño A warming of the Pacific Ocean. Winters: West = Stormy South = Cold, wet Northeast = warmer

Think about it… Brainstorm what negative effects you think would be likely to accompany the rise in temperature, including natural disasters. Think about the impacts on weather… Droughts, floods, mudslides, hurricanes, typhoons… El Nino Video

Cause and Effect El Nino Cause: Develop when easternly winds weaken. Warm surface air creates more thunderstorms over the central and eastern pacific Effect: Subtropical jet stream is energized, storms lead to frequent mudslides in SO. CAL. And a wet winter in the Southern US

La Niña A cooling of the Pacific Ocean. Dry in southeast. Cool, wet in northwest. La Niña A cooling of the Pacific Ocean. Dry in southeast. Cool, wet in northwest.

Cause and Effect La Nina Cause: Stronger than normal trade winds push warm water farther west Effect: Polar jet stream is amplified, brings cold air to northwest. Subtropical jet stream moves northward bringing moisture, heavy rains, and mountain snows to the Pacific Northwest. El Nino and La Nina Visualization

Man made Causes Burning of hydrocarbons – Fossil fuels (oil & coal), releases CO2 and pollutes the atmosphere. Population Increase - means more food and methods of transportation. -- more fossil fuels must be burned to produce methane = manure ---- more agriculture, more methane

Man made Causes Deforestation -- the trees that convert our CO2 to oxygen are being demolished because we're using the land that we cut the trees down from as property for our homes and buildings.