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Class #20: Friday, October 20, 2010. The C and D Climate Types. The C climate types: moist, subtropical mid-latitude climates. General characteristics: humid with mild winters (average temperature between 27°F and 64°F); distinct summer and winter seasons, ample precipitation
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Class #20: Friday, October 20, 2010 The C and D Climate Types Friday, October 15, 2010
The C climate types: moist, subtropical mid-latitude climates • General characteristics: humid with mild winters (average temperature between 27°F and 64°F); distinct summer and winter seasons, ample precipitation • Extent: on the eastern and western regions of most continents, from about 25° to 40° latitude • Major types: humid subtropical (Cfa), marine (Cfb), and dry-summer subtropical or Mediterranean (Csa, Csb) Friday, October 15, 2010
Categorization of C climates • C Moist with mild winters • w dry winters • s dry summers • f wet all seasons (no dry season) • a summers long and hot • b summers long and cool • c summers short and cool • See table on page 480 for details Friday, October 15, 2010
Cfa: The humid subtropical climate • Found principally along the east coasts of continents 25° – 40° latitude; Southeastern section of the US, eastern China, and southern Japan. In SH, southeastern SA, Southeastern coasts of Africa and Australia • Hot muggy summers: under the influence of the western side of subtropical highs, where maritime tropical air flows poleward Friday, October 15, 2010
Cfa: The humid subtropical climate • Upper-level ridges produce devastating heat waves • High temperatures, dew points make summer weather more uncomfortable than the tropics • Winter weather can be quite changeable • Little snow • Adequate and well-distributed precipitation through the year Friday, October 15, 2010
Cfa: The humid subtropical climate • Summer thunderstorms are common • Tropical cyclones contribute to rainfall total in the US and China • Winter precipitation in mid-latitude cyclones • Vegetation: in southeast US, thick pine forest mixed with oak at higher latitudes • Example: Mobile, Alabama Friday, October 15, 2010
Cfb: West coast marine, or marine climate • Along the west coast of most continents, from latitude 40° to about 60°. • Dominated by prevailing winds from the ocean that moderate the climate (warmer winters, cooler summers) compared to farther inland. Summers are quite cool. If short, Cfc. • Limited in horizontal extent by coastal mountains Friday, October 15, 2010
Cfb: West coast marine, or marine climate • In western Europe, Cfb extends well inland • For much of the year, low clouds, fog, drizzle • Adequate precipitation in all months, from mP air masses, is light or moderate • Mountains enhance precipitation • Along NW coast of NA, less rain in summer, with northward migration of the subtropical high Friday, October 15, 2010
Cfb: West coast marine, or marine climate • Characterized by a low annual temperature range for such high latitudes • Frequent precipitation and overcast skies act to minimize daily variation in temperature • Dense forest of Douglas fir where precipitation is heavy • Example: Port Hardy, Vancouver Island, Canada Friday, October 15, 2010
Csa,b Dry-summer subtropical, or Mediterranean climate • On west coasts south of the Cfb climates • On the shores of the Mediterranean Sea • Summer dryness more pronounced than the Cfb climates • Mild (Csb) to hot (Csa) dry summers • Dryness due to the sinking air in the subtropical highs and their diversion of storms poleward in summer Friday, October 15, 2010
Csa,b Dry-summer subtropical, or Mediterranean climate • During winter, subtropical highs move south, and extratropical cyclones provide rain • Typically, mild wet winters • Csa: interior Mediterranean (Sacramento) • Csb: coastal Mediterranean (San Francisco) Friday, October 15, 2010
Csa,b Dry-summer subtropical, or Mediterranean climate • Csa • Summers are hot • Winters a little colder than Csb • Wider annual variation in temperature • Csb • Upwelling keeps air cool all summer • Often shrouded in low cloud and fog • Small annual range in temperature Friday, October 15, 2010
Csa,b Dry-summer subtropical, or Mediterranean climate • Snow is rare • Land supports chaparral, a scrubby type of low-growing woody plants and trees • Mediterranean Sea: summers not so dry as NA (far from subtropical high); also warmer (no upwelling) Friday, October 15, 2010
Cw climate type • Winter dry season • Associated with the winter monsoon in Asia • Prevailing winds around continental High • Northern India and portions of China • In lower latitudes, higher altitudes keep them from being tropical because they are too cool Friday, October 15, 2010