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