The pattern of weather that occurs in an area over many years. Determines the kinds of plants & animals that can live in an area and influences how people live. It’s the average of the area’s temperatures, precipitation, air pressure, humidity & the number of days of sunshine in the area.
What factors affect climate? 1. Latitude – the measure North & South from the equator, affected by direct solar radiation 1.Polar Zones – solar radiation hits at a lower angle, heat is spread out more, it’s never warm here 2.Tropical Zones – (the tropics) warmest areas due to the direct solar radiation 3.Temperate Zones – more moderate temps, most of the United States is in this zone
What factors affect climate? 2. Landforms Along similar latitudes, mountains are colder than other locations at sea level due to the higher elevation. There are fewer molecules available to absorb the heat at the higher altitudes and the atmosphere is thinner.
What factors affect climate? 3. Locations of lakes and oceans Large bodies of water can affect coastal areas by absorbing or giving off heat, making these areas warmer in the winter & cooler in the summer than inland areas at similar latitudes
What factors affect climate? 4. Ocean currents Currents are warmer near the equator. When they flow past higher latitudes, they warm the land that they pass. When they cool off and flow back towards the equator, they cool the air & climates of nearby land
Other factors affecting climate: Rain Shadows The side of the mountain facing the wind gets more rain because as the air rises & cools it drops its moisture (precipitation falls!) On the opposite side of the mountain air drops, heats up & dries the land (deserts found here)
How do cities affect climate? In large cities streets, buildings, and parking lots heat up. Air pollution traps this heat. Temperatures can be 5 degrees higher in the city than in rural areas.
Different Types of Climates: 6 types: tropical, dry, continental, mild, polar & high elevation Depending on the different climate, plants and animals have adapted to live in that area… HOW?
Plants & Animals Survive Due to: Structural Adaptations – fur on animals in cold regions, thick skin and prickles on cacti in deserts protect & help hold water Behavioral Adaptations-hibernation, desert turtles get the water they need from their food
Why do we have different seasons? Because the Earth is tilted at an angle. As it revolves around the Sun, areas receive more direct solar energy at different times of the year.
Major Climate Changes El Nino: Changes the winds to allow upper waters of the Pacific Ocean to flow towards South America, warming the oceans 1 – 7 degrees Can affect weather patterns Change the position & strength of the jet streams Changes atmospheric pressure in California Can cause droughts in Australia & Africa Affects monsoons in Indonesia
Major Climate Changes La Nina: Stronger than usual winds blowing across the Pacific Causes warm water to collect in the western Pacific May cause droughts in the southern U.S. & floods in the northwest U.S.
If fossils of tropical plants are found in arctic regions, what does it tell us about climate changes?
What has caused climate changes in the past? *Catastrophic events- Volcanic eruptions & meteor collisions can blow large amounts of ash & dust into the atmosphere *Varying amounts of energy given off by the sun possibly due to sunspots *Changes in the tilt of the Earth *Movement of plates affects the land & ocean distribution & heat transfer, which affects wind patterns & the amount of precipitation
Why are there changes in the climate now? The Greenhouse Effect The natural heating due to gases in the atmosphere trapping heat Common Greenhouse gases = water vapor, carbon dioxide & methane make life possible on Earth, but if they warm up too much, it’s a problem. It creates…
Global Warming The average global temperature of Earth is rising Results of global warming: melting glaciers would cause sea levels to rise which would increase flooding in coastal areas What causes global warming?
Choices PEOPLE make! 1.Burning fossil fuels – natural gas, coal & oil used for energy. All of these contain carbon which combines with oxygen to form carbon dioxide. This has caused a 25% increase in CO2 in the last 150 years! 2.Deforestation – destroying & cutting down trees increases CO2 levels because the trees are no taking in CO2 for the natural process of making wood & leaves
How do we reduce CO2 levels? Conserve electricity (means less fossil fuels are burned) Plant vegetation to help remove CO2 from the atmosphere naturally