1. Earth’s Weather and Climate

2. Our Weather and Climate
The condition of the atmosphere at a certain time and place.
Changes daily
Climate
The overall weather patterns of an area
Changes occur over long periods of geologic time

3. Solar Energy Earth receives energy from the sun by radiation.
Radiation is the transfer of energy as electromagnetic waves.
The suns radiation enters Earth as
Visible light
Infrared waves - heat
Ultraviolet radiation

4. Solar Energy from the Sun
Energy from the sun is transferred around Earth by radiation and convection.

5. Energy from the sun creates convection currents in the atmosphere and oceans

6. Convection Currents
Convection is the transfer of thermal energy by the circulation of liquids and gases.
Warm air or water rises
It’s less dense
Cool air or water sinks
It’s more dense

7. Ocean Currents Warm water rises and cooler water sinks

8. Wind and Ocean Currents
Influence Earth’s Weather and Climate

9. Temperature of Our Oceans
Ocean water cools down and warms up much slower than land or air.
Oceans keep temperatures for nearby land much more moderate.
Temperatures are less extreme
Doesn’t get too cold or too hot
This keeps coastal areas cooler in the summer and warmer in the winter.

10. Land and Sea Breezes
Winds caused by uneven heating of air above ocean water and land.
Land heats up and cools down much faster than ocean water.
Land gets much hotter during the day and much cooler at night.

11. Coastal Areas experience Sea Breezes during the day

12. Coastal Areas also Experience Land Breezes at Night

13. Sea Breezes by Day Land Breezes by Night

14. Valley and Mountain Breezes

15. Ocean Currents Stream like movements of water in oceans
Heat is transferred around the world by ocean currents through convection.
Over ½ the heat that reaches the Earth from the sun is absorbed by the oceans surface.

16. Surface Currents Currents at or near the surface of the ocean
Caused by WINDS!
Affect weather and climate for coastal regions around the world.
Warm currents originate at the Equator
Cold currents originate at the Poles

17. Deep Water Currents Deep currents far below the surface of the ocean.
Water is cold and salty which makes it more dense and sinks to the ocean floor.

18. Currents Trade Places
Water from deep currents get warmer as they reach the equator and starts to rise.
Water from surface currents get colder as they reach the poles and starts to sink
Heat is transferred by convection currents, in our oceans. Warm water rises and cold water sinks

19. Ocean Water Currents

20. Changes in Ocean Currents
El Nino – the warming of water
in the Pacific Ocean
La Nina – the cooling of water
in the Pacific Ocean

21. Causes Changes in Weather
El Nino Weather
Rain and flooding along the Pacific Coast
Tornadoes and thunderstorms in South US
Fewer than normal hurricanes in the Atlantic
La Nina Weather
Snow and rain on the west coast
Cold weather in Alaska
Warm weather in the rest of the USA
Drought in the south west
More hurricanes in the Atlantic

22. Warm air rises and cool air sinks
Wind currents
Warm air rises and cool air sinks

23. Wind Currents Created by differences in Air pressure
Caused by unequal heating of the Earth from the sun
Equator – Warm, less dense air
Low air pressure
Poles – Cold, more dense air
High air pressure

24. Atmospheric/Air Pressure
The force of the air pushing on any surface.
Measured in Millibars
Decreases with altitude
Changes with air temperatures
Creates wind!

25. Barometer – Measures Air Pressure

26. Air Pressure Weather Map Isobars – Lines on a weather map that show equal Atmospheric Pressure
H = High Pressure L = Low Pressure

27. Convection Cells of Air Create Winds

29. Jet Streams High-speed winds that can reach up to
500 km/hour high up in the sky.

30. Wind Speed
Measured by an anemometer
Digital

31. Weather Map showing Isobars and Windspeed/Direction

32. Air Masses – large bodies of air that have similar temperature and moisture throughout

33. Types of Air Masses Continental - form over land; dry
Maritime - form over water; wet
and
Tropical - form in a tropical region; warm
Polar – form in a polar region; cold

34. Air Masses mP – Maritime Polar Cold and Wet
cP – Continental Polar Cold and dry
mT – Maritime Tropical
Warm and Wet
cT – Continental Tropical
Warm and Dry

35. Air Masses

36. Fronts Boundary that forms between two different air masses
4 types of fronts: Cold, Warm, Occluded, Stationary

37. Cold Front When a cold air mass replaces a warm air mass
Produces colder temperatures and more precipitation

38. Warm Front When a warm air mass replaces a cold air mass.
Creates warmer temperatures and some precipitation.

39. Weather Map

40. The amount of moisture or water vapor in the air.
Humidity
The amount of moisture or water vapor in the air.

41. Relative Humidity
Relative Humidity – the amount of moisture the air contains compared with the maximum amount it can hold at a particular temperature.

42. Measuring Humidity Psychrometer Hygrometer Measures Relative Humidity
Measures Humidity
Psychrometer

43. Severe Weather Weather that can cause property damage and even death.
Thunderstorms
Tornadoes
Hurricanes

44. Thunderstorms
Intense weather systems that produce strong winds, heavy rain, lightning and thunder
Occur when warm, moist air rises rapidly in an unstable atmosphere.
Can cause high winds, hail, flash floods, and tornadoes.

45. Tornadoes
A rotating column of air that has high wind speeds and low central pressure that touches the ground.
Starts as a funnel cloud formed from a cumulonimbus cloud
Produced by thunderstorms
75% occur in the US

46. Wall Cloud

47. Wall Cloud – Take Cover

48. Hurricanes Most powerful storms on Earth
Form in warm ocean waters by the equator
Fueled by warm water and moist air
Die out over cold water and land

49. Hurricanes, Typhoons, Cyclones Form in warm ocean waters by the equator