1. What Causes Weather?

2. We should have discovered that land and water do not heat up at the same rate. If things went correctly, we should know that land heats up & cools down faster than water. Therefore, the sun will heat up land quicker than oceans.

3. That means that the hot air over land rises and cool air from over the ocean will blow in to take its place.

4. This uneven heating of the Earth causes hot air to rise and cold air to sink, leading to movement of air in the atmosphere.

5. atmosphere A blanket of air surrounding the Earth
made up of gases, water, dust, & other small particles
It is divided into layers, based on temperature
troposphere, stratosphere, mesosphere, thermosphere

6. Troposphere Bottom layer of the atmosphere
most of Earth’s weather occurs here
8 miles thick (13 km)
Supersonic aircraft fly in this layer

7. Stratosphere 2nd layer of the atmosphere contains the ozone layer
some aircraft fly in this layer
21 miles (50 km)

8. Mesosphere Third layer of the atmosphere coldest layer
this is the layer where meteors burn up
50 miles (80 km)

9. Thermosphere The top layer of the atmosphere very high temperatures
gradually merges into space
196 miles (320 km)

10. Air pressure Gravity pulls on air
lower in the atmosphere means greater air pressure
cold air is heavier than warm air
when cold air sinks it forces up warm air

11. Wind Movement of air air is constantly moving 3 reasons
gravity, temperature, Earth’s rotation
moves from high to low or cold to warm

12. Local Wind A wind that results from a local difference in temperature
wind blowing in from the sea over a beach during the day
wind blowing from land to water at night

13. Prevailing winds Global winds always blow in the same direction
caused by uneven heating of the Earth’s surface and rotation
creates many circles of air
moves in curved paths

14. ???????? What two factors cause prevailing winds?
In what layer of the atmosphere does most weather occur?
In what layer is the ozone layer?
What drives all weather on the Earth?
Why is the climate warmer near the equator?