1. Rain Shadow and Greenhouse Effect
Unit 3: Meteorology Part 2

2. Kohala Mountain, Hawaii
Why is one side of the mountain dry and barren, while the other side is full of vegetation?

3. Cascade Mountain Ranges

4. Let’s Review…. As warm air rises, it COOLS.
Cool air has a LOWER capacity which means the air can hold LESS water
Water condenses and turns into clouds
Precipitation occurs
As cool air sinks, it WARMS
Warm air has a HIGHER capacity which means the air can hold MORE water
Water evaporates from the land and causes clouds to disappear
Dry, desert-like conditions

5. The Rain Shadow WINDWARD SIDE LEEWARD SIDE PREVAILING WESTERLIES
5. As air travels over the mountain, it begins to sink.
4. PRECIPITATION! Rain, snow, or hail
1. Water Evaporates = cool, wet air
6. Water evaporates causing dry environments
3. As the air rises, it expands & cools more. Water condenses and clouds form.
PREVAILING WESTERLIES
2. Air is FORCED upward by the mountain range
PACIFIC OCEAN
OREGON
CASCADE MOUNTAINS
IDAHO

6. Living in Idaho, we experience the Rain Shadow Effect every day
Living in Idaho, we experience the Rain Shadow Effect every day. Idaho’s weather comes in from the __________ Ocean and crosses the ______________ or coastal Mountains. As the air comes in off the ocean, it rises up the side of the mountains. As it rises, it (expands/contracts) and (warms/cools). This causes the relative humidity to (increase/decrease). When air becomes saturated (condensation/evaporation) will occur to form clouds. This occurs on the (windward/leeward) side of the mountains.
Once air crosses over the top of the mountain range it flows down to east or (windward/leeward) side. As the air flows down, it sinks and (expands/contracts) as the air begins to warm. The relative humidity (increases/decreases) as the air warms producing very (moist/dry) weather. This makes the (windward/leeward) side of the mountain the rain shadow side.
PACIFIC
CASCADE

7. How is weather affected by human actions?

8. Severe weather is powered by…
ENERGY
Severe weather is powered by…
1. Fusion in the sun produces energy in the form of radiation
2. Earth absorbs the radiation
3. Unequal heating of the Earth.
6. Energy released into the atmosphere powers hurricanes, tornados, etc.
5. Clouds form by releasing energy from water
4. Differences in air pressure

9. The more energy that is absorbed by Earth’s surface, the more severe weather we get!

10. The Greenhouse Effect 2. Reflected Radiation
Energy that is reflected by the Earth’s surface is REABSORBED by greenhouse gases
The Greenhouse Effect
Absorbed Radiation
Earth absorbs radiation from the sun
3. Greenhouse Gases
Greenhouse gases emit the radiation back to the Earth.

12. Greenhouse Gases result in Global Warming
1. Carbon Dioxide
Burning of coal, oil, fossil fuels, etc…
Deforestation (clearing of forests); Less trees/plants that are able to remove CO2 from the atmosphere
Volcanoes, fires, and respiration (breathing)
2. Methane
Garbage buried in landfills
Animal waste
3. Water vapor due to increased evaporation
4. Chlorofluorocarbons (CFCs)
Refrigerants and aerosols

13. So What? Polar ice caps are melting Increases in strong storms
Rise in sea level
Increases in strong storms
Hurricanes get strength from warm ocean water