1. Climate
Chapter 14

2. Climate

3. What is climate? What is the definition of climate from Chapter 12?
Long term variations in weather for an area
What is climatology?
The study of Earth’s climate

4. Normals
Climate data is compiled from meteorological records continuously.
This data is averaged on a monthly or annual basis for 30 years to determine the normals.
What is a normal?
Standard value for a location
Do not describe daily weather conditions

5. Normals

6. What Causes Climate? Latitude: How would latitude affect climate?
Amount of solar radiation received at any one place differs. What areas receive the most?
Tropics
2. Topographic Effects
Large bodies of water heat and cool slowly
What does this mean for costal areas?
Remain warmer in winter
What do you think mountain climates are like?
Usually cooler due to higher elevation

7. Latitude

8. Topographic Effects

9. What Causes Climate? 3. Air Masses
Areas where air masses form have similar climate to the air mass itself

10. Climate Classification
Two Factors used:
1. Temperature
2. Amount of Precipitation
Koeppen classification system
Based on average monthly temp. and precipitation values

11. Tropical Climates Constant high temperatures
Most have large amounts of rain
Some have dry winters (Savannas)
Dramatic vegetation

12. Dry Climates 30% of Earth’s land area Largest climatic zone Deserts
Low precipitation
Scarce vegetation
Hot, tropical air

13. Mild Climates Humid Subtropical: SE United States
Subtropical high-pressure systems over oceans in summer
Warm, muggy weather during the summer
2. Marine West Coast: West United States
Constant inland flow of air off ocean
Mild winters, cool summers
Abundant precipitation
3. Mediterranean: Italy and Spain
Warm Summers

14. Continental Climate Three Zones Clashing tropical and polar air masses
Warm Summer
Cool Summer
Subarctic
Clashing tropical and polar air masses
What occurs when this happens?
Tornadoes
Rapid and violent changes in weather; extreme temperatures; A lot of precipitation in summer

15. Polar Climates Coldest regions on Earth Precipitation is low
Heat radiation by Earth’s surface is low.
Too low to produce strong convection currents
What do convection currents produce?
Heavy precipitation

16. Microclimate
A localized climate that differs from the main regional climate
Heat Islands
Buildings and concrete cause climate to be warmer than surrounding rural areas
Concrete radiates a lot of heat back in to the air

17. Heat islands

18. Ice Ages Periods of extensive glacial coverage.
Average global temperature decreases by 5°C
Most recent ended about 10,000 years ago

19. Short-Term Climate Change:
Seasons: short-term periods of climatic change
Caused by regular
variations in daylight,
temperature, and
weather patterns.
Tilt of Earth
Orbit of Earth
Amount of sunlight

20. Short-Term Climate Change
El Nino: warm ocean current
Occasionally develops off South America
Warms air on South American coast

21. Natural Climate Change
Solar Activity
Maunder minimum: low sunspot activity corresponds to unusually cold climatic episode
Earth’s Orbit: varies from circular to elliptical
What do you think happens when the orbit goes from circular to elliptical?
Elliptical=Earth passes closer to the sun=warmer temps
Earth’s Wobble: Earth does not always point to the North Star which changes effects of seasons
Volcanoes: How would this affect climate?
Volcanic ash can block solar radiation

22. Greenhouse Effect Retention of heat by the atmosphere Global warming:
Keeps Earth from getting too hot or too cold
Global warming:
Theory that the release of too much CO2 in the atmosphere is causing an increase in global temperatures
Deforestation contributes to global warming