Transcript Slide 1

Meteorology 10 - Weather and Climate
Fall 2008
CHAPTER 13
FOCUS: defining climate zones
Global
Climate
Chapter 13: Global
Climate
• A world with many climates
• Climatic classification - the Köppen system
• The global pattern of climate
A World with Many
Climates
TEMPERATURE VS PRECIPITATION
These climates can be categorized based on scale
Microclimate:
Mesoclimate:
Macroclimate:
Global climate:
• The fact that land masses heat up and
cool off more quickly than do large bodies
of water means that variations in
temperature between summer and winter
will be far greater over continental interiors
than along the west coastal margins of
continents.
– Global temperature variations
Global Temperatures
• controls on climate (7):
- intensity of sunshine and its variation with
latitude
- distribution of land and water
- ocean currents
- prevailing winds
- location of high and low pressure areas
- mountain barriers
- altitude
• ‘bending’ of isotherms near continents
Figure 13.1: Average annual sea-level temperatures throughout the world (°F).
Fig. 13-1, p. 355
Global Precipitation
• relationship to areas of rising and sinking
air
• influence of ITCZ
• influence of orographic uplift and rain
shadows
• Precipitation is most abundant where air rises,
and least abundant where it sinks.
Fig. 13-2, p. 356
Stepped Art
Fig. 13-2, p. 356
Climatic Classification the Köppen System
Each group contains subregions that describe special regional characteristics
such as; seasonal changes in temperature and precipitation
Scheme criticized – but revised; lengths of growing seasons and average
summer temperatures
Climatic Classification - the
Köppen System
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Tropical moist climates
dry climates
moist midlatitude climates with mild winters
moist midlatitude climates with severe winters
polar climates
criticisms of the Köppen climate classification
system
• The Köppen climate classification system was
first published in 1918.
Fig. 13-6, p. 361
Stepped Art
Fig. 13-6, p. 361
The Global Pattern of
Climate
The Global Pattern of Climate
• Major features of Earth’s climate
distribution
• local variations within larger climate
regions
Tropical Moist Climates
(Group A)
• tropical wet (Af) **what are the temp & precip indicators**
• Tropical rain
forests and monsoons
are included in this
category.
Tropical Moist Climates
(Group A)
• tropical monsoon (Am)
Tropical Moist Climates
(Group A)
• tropical wet and dry (Aw)
Dry Climates (Group B)
• arid (BW)
• Deserts and steppes are included in this category.
Dry Climates (Group B)
• semiarid (BS)
Moist Subtropical Mid-Latitude
Climates (Group C)
• humid subtropical (CfA)
• Hot, muggy summers
and relatively mild
winters are typical
of this category.
Moist Subtropical Mid-Latitude
Climates (Group C)
• marine (CfB)
Moist Subtropical Mid-Latitude
Climates (Group C)
• Mediterranean (Cs)
Moist Continental Climates
(Group D)
• humid continental with hot summers (Dfa)
• This category is sometimes referred to as a
Mediterranean climate.
Moist Continental Climates
(Group D)
• humid continental with cool summers (Dfb)
Moist Continental Climates
(Group D)
• subpolar (Dfc)
Polar Climates (Group E)
• polar tundra (ET)
• This climate is not necessarily found at in the polar
regions; it is sometimes found at high altitudes. There,
however, it is called a Highland climate (Group H).
Polar Climates (Group E)
• polar ice caps (EF)
Highland Climates (Group H)
• altitude effects are similar to latitude
effects
How a rainshadow effect works…
Stepped Art
Fig. 13-5, p. 360
• The hottest places on earth tend to occur in the subtropical
deserts of the NH, where clear skies and sinking air, coupled
with low humidity and a high summer sun beating down upon
a relatively barren landscape, produce extreme heat
• The coldest places on earth tend to occur in the interior of
high-latitude land masses. The coldest areas on the NH are
found in the interior of Siberia and Greenland, whereas the
coldest area of the world is the Antarctic
• The wettest places in the world tend to be located on the
windward side of mountains where warm, humid air rises
upslope. On the downwind (leeward) side of a mountain there
often exists a “dry” region, known as a rain shadow
Let’s look at some records….
Figure 1, p. 359
SUMMARY
KEY TERMS