Chapter 8 Climatic Zones and Types

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Chapter 8 Climatic Zones and Types
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Climate Classification

• The Purpose of Classifying Climates
• to understand distribution of climates
• to compare climates of different places
• Ancient Greek Classification System

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Major Climate Groups

• Tropical Humid Climates (Zone A)
• Dry Climates (Zone B)
• Mild Midlatitude Climates (Zone C)
• Severe Midlatitude Climates (Zone D)
• Polar Climates (Zone E)
• Highland Climate (Zone H)

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Modified Köppen Climate Classification System
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Köppen Letter Code System
E D C B A B C D E
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Climate Regions of the World
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Empirical System

• Based on
• Temperature
• Precipitation
• Helpful to determine
• Origins
• Patterns
• Change

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World Distribution of Major Climates
Animation (Seasonal Pressure and
Precipitation Patterns)

• Three Questions
• Where are the various climate types located?
• What are the characteristics of each climate?
• What are the main dominant controls of these
  climates?

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Introduction toClimographs(example)
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Tropical Humid Climates (Zone A)

• Tropical Wet (Af)
• Tropical Monsoon (Am)
• Tropical Savanna (Aw)

• 15-20 degrees N/S of equator
• winterless, daily sun
• warm and moist
• ITCZ thermal convection/uplift

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Tropical Wet
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Tropical Monsoon
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Monsoonal conditions
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Tropical Savanna
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Tropical Savanna and the ITCZ
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Dry Climates (Zone B)

• 30 land area
• dry because lack of uplift
• deserts lt 10 rain/yr
• steppes 10-25 rain/yr
• rainfall is scarce, unreliable and intense

• Subtropical Desert (BWh)
• Subtropical Steppe (BSh)
• Midlatitude Desert (BWk)
• Midlatitude Steppe (BSk)

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Influence of Subtropical Highs
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Subtropical Desert and Steppe
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Midlatitude Desert and Steppe
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Mild Midlatitude Climates (Zone C)

• Mediterranean (Csa and Csb)
• Humid Subtropical (Cfa and Cwa)
• Marine West Coast (Cfb and Cfc)

• 30-60 degrees N/S
• variable because lack constant heat of tropics
  and continuous cold of polar areas
• alternating air masses

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Mediterranean
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Humid Subtropical
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Marine West Coast
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Severe Midlatitude Climates (Zone D)

• 40-70 degrees N
• broad temperature range (continentality) long
  cold winter, short summer
• variable precipitation, more near the coasts

• Humid Continental (Dfa, Dwa, Dfb and Dwb)
• Subarctic (Dfc, Dwc, Dfd, Dwd)

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Humid Continental
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Subarctic
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Polar Climates (Zone E)

• Tundra (ET)
• Ice Cap (EF)

• very cold, no significant warming
• dry, but little evaporation so humid

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Tundra
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Ice Cap
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Highland Climate (Zone H)
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• Highland dominant controls
• Altitude
• Slope aspect and slope angle
• Weather variability

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Global Patterns Idealized

• General Models of Climate Distribution

• Idealized seasonal precipitation patterns and
  climates along the west coasts of continents.

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Climatic Distribution in Africa A Practically
Perfect Example
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Global Climate Change

• Time scale of observations determine what
  patterns of change stand out in the record

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Global Climate Change

• Determining Climates of the Past
• Animation (End of the Last Ice Age)
• Dendrochronology
• tree ring samples
• Oxygen isotope analysis
• of oceanic sediments
• Ice cores
• O O
• Pollen analysis
• preservation in crustal
• materials

18 16
/
ratio
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Global Climate Change

• Causes of Long-Term Climate Change
• Animation (Orbital Variations and
• Climate Change)
• Volcanic activity and meteor impacts
• Fluctuations in orbital output
• Variations in Earth-Sun relations
• Greenhouse gas concentrations
• Feedback mechanisms
• The roles of the ocean

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• Climate Models
• Global Circulation Models (GCMs)
• Mathematical models of Earths climate system
• Computer simulation models of future climates (3)
• Climate prediction (IPCC)
• global average temperature increase
• global warming changes in global climates

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Global Consequences

• Climate changes will be observable in our
  lifetime
• Climates may warm 1 degree F per 25 years (on
  average)
• Precipitation will increase at higher latitudes
  and decrease at lower latitudes
• As sea ice melts, sea levels rise
• More atmospheric/oceanic disturbances
• hurricanes, tornados
• heat waves, droughts
• extremely variable conditions

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Activity

• Read Ch. 8
• In-class
• Hand out w/ specific climate type(s)
• Determination of climograph(s)
• 10 groups, 1 investigation per group
• Sign-in!