1. Lesson Overview Lesson OverviewClimate Lesson Overview 4.1 Climate

2. Lesson Overview Lesson OverviewClimate THINK ABOUT IT When you think about climate, you might think of dramatic headlines: “Hurricane Katrina floods New Orleans!” or “Drought parches the Southeast!” But big storms and seasonal droughts are better described as weather rather than climate. What is climate, and how does it differ from weather? How do climate and weather affect organisms and ecosystems? climate

3. Lesson Overview Lesson OverviewClimate Weather and Climate Weather is the day-to-day condition of Earth’s atmosphere. Climate refers to average conditions over long periods of time Climate is rarely uniform even within a region. Environmental conditions can vary over small distances, creating microclimates. Ex: Northern Hemisphere: south-facing sides of trees and buildings receive more sunlight, and are often warmer These differences can be very important to many organisms. Weather & Climate

4. Lesson Overview Lesson OverviewClimate Roll Cloud roll cloud

5. Lesson Overview Lesson OverviewClimate Factors That Affect Climate What factors determine global climate? Water cycle, Latitude, altitude & winds, air pressure, ozone, shape of land, natural disaster eg volcanoes, people!

6. Lesson Overview Lesson OverviewClimate EFFECTS OF HUMIDITY ON THE HUMAN BODY " Humidity" refers to the presence of water vapor in the atmosphere. Warm air rises, cool air sinks relative humidity–how close to saturation is water vapor EX: Colder air cannot hold as much water vapor as warmer air. So: as temperature, the relative humidity will, and likewise, as temperature, the relative humidity will This is why desert areas, even with temperatures 20 deg. warmer than humid areas, can feel cooler to you.

7. Lesson Overview Lesson OverviewClimate Latitude: due to curvature of Earth-Temperatures decrease as you move away from the equator. Altitude & Winds: Locations at a higher altitude have colder temperatures. Oceans heat up and cool down much more slowly than land. coastal locations tend to be cooler in summer & warmer in winter than places inland at the same latitude and altitude. Air Pressure: Low pressure- air is usually rising, cools, condenses and forms clouds High pressure-sinking dry air, usually sunny

8. Lesson Overview Lesson OverviewClimate Relief (shape of Land): Mountains receive more rainfall because as air is forced over the higher ground it cools and condenses Slopes facing the sun are warmer. south facing slopes in the northern hemisphere are usually warm and slopes facing north in the southern hemisphere are warmest.

9. Lesson Overview Lesson OverviewClimate Human influence Burning of Fossil fuels: CO2 The number of trees being cut down has also increased, reducing the amount of carbon dioxide that is taken up by forests. “greenhouse gases” function like glass in a greenhouse, allowing visible light to enter but trapping heat through a phenomenon called the greenhouse effect.

10. Lesson Overview Lesson OverviewClimate Coriolis Force "Coriolis force" -deflection due to the Earth’s rotation As air moves from high to low pressure in the northern hemisphere, it is deflected to the right by the Coriolis force. In the southern hemisphere, air moving from high to low pressure is deflected to the left by the Coriolis force. The Coriolis force is zero right at the equator. effect