Transcript Factors that Affect Climate

Weather and Climate
• Weather – atmospheric conditions over
a short period of time (day), studied by
meteorologists.
• Climate – atmospheric conditions over
a long period of time (months and
years), studied by climatologists.
• Of main interest is precipitation and
temperature.
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Identify the factors
that affect climate
and explain
how each
affects climate.
North or South of the Equator makes a difference
on the temperature and the wind patterns
High Latitudes: Warm when the poles are tilted towards the
sun and Cool when the poles are tilted away from the sun
Low Latitudes: Between the tropic of Cancer
and Tropic of Capricorn, warm hot climates
THE EARTH’S AXIS - Seasons
The earth’s axis is tilted from the vertical by 23 ½ degrees.
The earth's orbit and tilt
A common misconception is that the seasons are caused by
how far the earth is from the sun.
In Canada, we are actually closer to the sun in the winter time
by about 900 000 kilometers.
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As we move from December to June the number of daylight hours
increases due to the tilt of the axis (earth surface receives more
direct sunlight). June to December daylight hours get shorter earth
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cools.
Summer – Energy
more intense
Winter – Energy less
intense
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How does latitude
affect climate?
Temperature
As latitude ________,
increases the average
decreases
annual temperature _________.
0°
Latitude
90°
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How does closeness to a large
body of water affect climate?
moderates the temperature.
Water __________
Cooler summers. _______
Warmer winters.
_______
Cities A & B are located
at the same latitude.
City B is closer to a large
body of water.
Its temperature line is
flatter (moderated).
Washington DC - Man made body of water. Why?
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The leeward
sides of the
Adirondacks &
Catskills
receive much
less
precipitation
The windward sides of the
Adirondacks & Catskills
receive a great deal more
precipitation
How does the
Orographic Effect
affect climate?
cool, moist
Windward Side: ___________
warm, dry
Leeward Side: _____________
Temperature drop of 1ºC for
each 100 m of elevation.
We live in the troposphere.
Temperature decreases
with elevation.
During summer, temperature is strongly controlled by elevation -- cold at the
higher reaches of the Alaska and Brooks Ranges, and warmer in the lowlands.
How does elevation
affect climate?
Temperature
increases the average
As elevation _________,
annual temperature __________.
decreases
Elevation
Water covers 70% of the earth’s
surface.
Water has a high heat capacity.
Water serves as a reservoir of
heat.
Ocean currents distribute the
absorbed heat around the world.
The primary
forces for
surface ocean
currents are:
1. Solar Heating
2. Winds
3. Gravity
4. Coriolis Effect
• Ocean currents enable the flow of energy from the tropics to
polar regions and back.
• Large ocean currents are constrained by the continental
masses found bordering the three oceanic basins.
Continental borders cause these currents to develop an
almost closed circular pattern called a gyre.
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How do ocean currents
affect climate?
Warm Currents: warmer climate
Cold Currents: cooler climate
WINDS
Wind Currents
Winds are due to the
relationship between air
temperature and air
density.
Changes in air pressure
cause movement of air.
Movement of air is called
WIND.
Global Winds
The jet stream are high
speed winds which travel
all around the earth. They
form at the boundary
between cold air and warm
air masses.
Cool air masses move
towards the equator.
Warm air masses move
towards the poles
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Upward movement - air lifts off the surface as the air is heated. This creates
an area of low pressure.
Downward movement -there is a piling up effect. This creates an area of high
pressure.
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Carioles Effect change of direction due to rotation
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cumulus
nimbus
(rain)
A cold front occurs when a
more dense air mass pushes
under a less dense air mass.
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cumulonimbus
cumulus
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Stratus (layer)
A warm front occurs when a less
dense air mass rides up over a
more dense air mass.
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Cirrus
Stratus
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