Global Climate

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Global Climate
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Keys to Climate
Temperature Regimes Climate the annual cycle of
prevailing weather conditions at a given place,
based on statistics taken over a long period What
determines temperature? 1. Latitude?Variation in
insolation?Temperature 2. Locationmaritime or
continentalmoderates that variation
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Keys to Climate
Global precipitation regions 1. Wet equatorial
belt 2. Trade-wind coasts 3. Tropical deserts
and steppes 4. Midlatitude deserts 5. Moist
subtropical regions 6. Midlatitude west
coasts 7. Arctic and polar deserts
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Keys to Climate

• Global Precipitation
• Seasonal precipitation patterns
• Uniformly distributed
• Summer precipitation maximum
• Winter precipitation maximum

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Climate Classification
Air Mass Source Regions
Group I Low-Latitude Climates Group II
Midlatitude Climates Group III High-Latitude
Climates
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Climate Classification
Dry and Moist Climates

• Dry Climates total annual evaporationannual
  precipitation
• Semiarid (steppe)
• Arid
• Moist Climates enough rain to keep soil moist
  all year, sustain year- round flow of larger
  streams
• Support forests or prairies
• Wet-dry Climates alternate wet and dry seasons

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Climate Classification
Highland Climates

• Usually cool
• Temperatures decrease with altitude
• Usually Moist
• Orographic precipitation

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Climate Classification
Climograph graph on which two or more climate
variables are plotted for each month of the year
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Climate Classification

• Seasonal Precipitation Patterns
• Equatorial regions wet all year
• Trade winds bring rain to equatorial/tropical
  east coasts
• Tropical deserts underlie subtropical high
  pressure cells

• Eastern sides of midlatitude continents warm
  moist air from western sides of subtropical highs
• Midlatitude west coasts subtropical highs block
  rainfall in summer

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Climate Classification

• Temperature Patterns
• Latitude temperatures drop from equator to poles
• Location continental interiors have greater
  range in temperature than coastal regions
• Elevation temperatures drop with elevation

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Low-Latitude climates (Group I)

• Four low-latitude climates
• Wet equatorial 2. Monsoon and trade-wind coastal
• 3. Wet-dry tropical 4. Dry tropical

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Low-Latitude climates (Group I)

• 1.Wet Equatorial Climate moist climate of the
  equatorial zone with a large annual water surplus
  and uniformly warm temperatures through the year
• Controlled by ITCZ
• Warm, moist mE and mT air masses
• Heavy convectional rainfall
• Uniform temperatures through the year
• Low-latitude rainforests

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Low-Latitude climates (Group I)

• 2. Monsoon and trade-wind coastal climate moist
  climate of low latitudes showing a strong
  rainfall peak in summer and short period of
  reduced rainfall in low-sun season
• Abundant rainfall
• Strong seasonal pattern
• Monsoon winds bring moist air to west coasts
• Trade winds bring moist air to east coasts
• Low-latitude rainforests

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Low-Latitude climates (Group I)

• 3. Wet-dry tropical climate climate of the
  tropical zone characterized by a very wet season
  alternating with a very dry season
• Very dry season at low sun
• ITCZ is far away
• Very wet season at high sun
• ITCZ is nearby
• Savanna vegetation

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Low-Latitude climates (Group I)

• 4. Dry Tropical Climate climate of the tropical
  zone with high temperatures and low rainfall.
• Center and east sides of subtropical high
  pressure cells
• Extreme heat, large daily temperature range
• Generally between 15º and 25º N and S
• Arid deserts and semiarid steppes

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Midlatitude Climates (Group II)
Six midlatitude climates 5. Dry Subtropical
6. Moist Subtropical 7. Mediterranean 8.
Marine West-coast 9. Dry midlatitude 10. Moist
Continental
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Midlatitude Climates (Group II)

• 5. Dry Subtropical Climate dry climate of the
  subtropical zone, transitional between the dry
  tropical climate and the dry midlatitude climate
• Poleward extension of dry tropical climate
• High annual temperature range
• Arid and semiarid subtypes

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Midlatitude Climates (Group II)

• 6. Moist Subtropical Climate moist climate of
  the subtropical zone, characterized by a moderate
  to large annual water surplus and a strong
  seasonal temperature cycle
• Eastern sides of continents, between 20º and 35º
  N and S
• mT air from western side of subtropical high
  pressure cells
• Warm humid summers, abundant rainfall
• Mild winters, ample rainfall
• Forest vegetation

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Midlatitude Climates (Group II)

• 7. Mediterranean Climate climate type of the
  subtropical zone, characterized by the
  alternation of a very dry summer and a mild,
  rainy winter
• Wet winter, dry summer
• West coast of continents
• Located between 30º and 45º N and S
• Vegetation shrubs and trees with hard leaves to
  resist water loss (sclerophylls)

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Midlatitude Climates (Group II)

• 8. Marine West-Coast Climate Cool, moist climate
  of west coasts in the midlatitude zone, usually
  with abundant precipitation and a distinct winter
  precipitation maximum
• Abundant precipitation, winter maximum
• Frequent cyclonic storms
• Mild winters, low annual temperature range
• West coasts, between 35º and 60º N and S

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Midlatitude Climates (Group II)

• 9. Dry Midlatitude Climate dry climate of the
  midlatitude zone with a strong annual temperature
  cycle and cold winters
• Interior of North America and Eurasia
• Within the rainshadow of mountain ranges
• Large annual temperature range
• Arid and semiarid, desert and steppe

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Midlatitude Climates (Group II)

• 10. Moist Continental Climate moist climate of
  midlatitude zone with strongly defined winter and
  summer seasons and adequate precipitation
  throughout the year
• Cold winters, warm summers
• Located in the polar-front zone
• Ample precipitation
• Forests and tall grasslands

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High-Latitude Climates (Group III)
11. Boreal Forest Climate Cold climate of the
subarctic zone in the northern hemisphere with
long, extremely severe winters and several
consecutive months of frozen ground

• Long cold winters, short, cool summers
• Source region for cP air masses
• Greatest range of temperature
• Boreal forests--needeleaf

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High-Latitude Climates (Group III)
12. Tundra Climate Cold climate of the arctic
zone with eight or more months of frozen ground

• Polar and arctic air masses
• Permafrost below surface
• Saturated soil in summer
• Tundra vegetationlow herbs and shrubs