MET 112 Global Climate Change - Lecture 4
Dr. Eugene Cordero
San Jose State University
Outline
 Energy balance: a latitudinal perspective
 Seasons
 Atmospheric circulation; quick view
 Climate game
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 Insolation – Incoming solar radiation
 Solstice – day of the year when the sun shines directly over 23.5
°S or 23.5°N
 Equinox – days of the year when the sun shines directly over the equator
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 The Sun’s angle of incidence:
– Lower sun angle, less incoming energy
– Higher sun angle, more incoming energy
 Length of time the Sun shines each day:
– Summer season, more sun hours
– Winter season, less sun hours
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What month do you think this graph represents?
a) December b) March c) June d) September
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What month do you think this graph represents?
0 of 70
1. December
2. March
3. June
4. September
0% 0% 0% 0%
D ec em be r
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M ar ch
S ep te m be r
Ju ne
12

 On June 21 st , at what latitude is the sun directly overhead at noon?
 On September 22 nd , at what latitude is the sun directly overhead at noon?
 How many hours of daylight are present at the
South Pole on February 20 th ?
 Where would you expect to have longer days;
45 ° N on June 21 st or 50 °S on Dec 21 st ?
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On June 21 st , at what latitude is the sun directly overhead at noon?
1. Equator (0)
2. 23.5
°N
3. 23.5
°S
4. 90 °N (north pole)
5. 90 °S (south pole)
0 of 70
0% 0% 0% 0% 0%
E qu at or
(0
)
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23
.5
°N
23
.5
°S
90
°N
(n or th
p ol e)
90
°S
(s ou th
p ol e)
16

Where would you expect to have longer days;
45 ° N on June 21 st or 50 °S on Dec 21 st ?
1. 45 °N
2. 50 °S
3. They are the same
4. Impossible to tell
0 of 70
0% 0% 0% 0%
C ho ic e
O ne
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C ho ic e
Tw o
C ho ic e
Th re e
C ho ic e
Fo ur
17

On September 22 nd , at what latitude is the sun directly overhead at noon?
1. Equator (0)
2. 23.5
°N
3. 23.5
°S
4. 90 °N (north pole)
5. 90 °S (south pole)
0 of 70
0% 0% 0% 0% 0%
E qu at or
(0
)
MET 112 Global Climate Change
23
.5
°N
23
.5
°S
90
°N
(n or th
p ol e)
90
°S
(s ou th
p ol e)
18

How many hours of daylight are present at the South Pole on February 20 th ?
1. 0 hours
2. 6 hours
3. 12 hours
4. 18 hours
5. 24 hours
0 of 70
0% 0% 0% 0% 0%
0 ho ur s
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6 ho ur s
12
h ou rs
18
h ou rs
24
h ou rs
19

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 A majority of the sun’s energy enters the Earth system in the tropics.
 The tropics thus becomes quite warm, while the poles relatively cool.
 The atmosphere attempts to bring the tropics and high latitude into equilibrium
– Weather systems ultimately act to bring warm air to higher latitudes and cold air to lower latitudes.
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Annual Surface Temperature

 Indicate the warmest and coldest areas of the
Earth.
 Consider the temperature at 60N latitude.
Indicate on the map the coldest and warmest places at 60N.
 What is the temperature difference between these locations
 What factors might explain this temperature difference?
 Why is there not a similar difference seen at 60S?
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Annual Surface Temperature
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 Latitude
– Higher latitude climates are generally
(cooler/warmer)
– Lower latitudes climates are generally
(cooler/warmer)
 Mountains
– Higher altitudes climate are generally
(cooler/warmer): cooler temperatures
– Windward side of mountains are generally
(cooler/warmer) and (wetter/drier), than leeward side
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 Latitude
– Higher latitude climates are generally
(cooler/warmer)
– Lower latitudes climates are generally
(cooler/warmer)
 Mountains
– Higher altitudes climate are generally
(cooler/warmer): cooler temperatures
– Windward side of mountains are generally
(cooler/warmer) and (wetter/drier), than leeward side
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 Seasonal temperature and precipitation patters are generally attributable to:
 Latitude
 Mountains and highlands
 Land and water location
 Prevailing winds
 Pressure and wind systems
 Ocean currents
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 Ocean Temperatures
– Coasts of continents are affected by ocean temperatures: Generally less temperature extremes compared to interior of continents
– Cold oceans: generally produce cooler/drier conditions
– Warm oceans: generally produce more warm/humid conditions
31
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Cold ocean
Warm ocean
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Dry
Humid
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 Rising and sinking motion associated with low and high pressure affects climate
 Areas where pressure seasonally low,
–
Tropics: rainy
 Areas where pressure seasonally high,
–
Subtropical high (30N/3OS): warm and dry
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January Average sea-level Pressure and surface wind pattern
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July Average sea-level Pressure and surface wind pattern
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A_B_D_ let’s check out clicker id’s out
1. E Q U
2. I E B
3. E L O
4. O U W
0 of 70
0% 0% 0% 0%
E
Q
U
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I E
B
E
L
O
O
U
W
41

Climate Game
Names ___________________________
 Match the city with the corresponding climatology by indicating the appropriate letter
 Sacramento, California (38 °N) _____________
 Phoenix, Arizona (33 °N) _____________
 Denver, Colorado (40 °N) _____________
 Iquitos, Peru (4 °S)
 Mobile, Alabama (30 °N)
 Winnipeg, Canada (50 °N)
 Fairbanks, Alaska (65 °N)
_____________
_____________
_____________
_____________

City A
1. Sacramento, California
2. Phoenix, Arizona
3. Denver, Colorado
67%
4. Iquitos, Peru
5. Mobile, Alabama
14%
6. Winnipeg, Canada
7% 7%
0%
2% 2%
7. Fairbanks, Alaska
S ac ra m en to
, C al ifo
P rn ia rizo ho en ix
, A
D en ve r, na
C ol or ad o
Iq ui to s,
P er u
M ob ile
, A la
W in ni ba m a pe g,
C an ad a
Fa irb an ks
, A la sk a
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City B
1. Sacramento, California
2. Phoenix, Arizona
3. Denver, Colorado
72%
4. Iquitos, Peru
5. Mobile, Alabama
6. Winnipeg, Canada 14%
12%
0%
2%
0% 0% 7. Fairbanks, Alaska
S ac ra m en to
, C al ifo
P rn ia rizo ho en ix
, A
D en ve r, na
C ol or ad o
Iq ui to s,
P er u
M ob ile
, A la
W in ni ba m a pe g,
C an ad a
Fa irb an ks
, A la sk a
MET 112 Global Climate Change
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City C
1. Sacramento, California
2. Phoenix, Arizona
3. Denver, Colorado
67%
4. Iquitos, Peru
5. Mobile, Alabama
19%
6. Winnipeg, Canada
7%
5%
0%
2%
0% 7. Fairbanks, Alaska
S ac ra m en to
, C al ifo
P rn ia rizo ho en ix
, A
D en ve r, na
C ol or ad o
Iq ui to s,
P er u
M ob ile
, A la
W in ni ba m a pe g,
C an ad a
Fa irb an ks
, A la sk a
MET 112 Global Climate Change
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City D
1. Sacramento, California
2. Phoenix, Arizona
3. Denver, Colorado
84%
4. Iquitos, Peru
5. Mobile, Alabama
6. Winnipeg, Canada
9%
4%
0% 0% 0%
2%
7. Fairbanks, Alaska
S ac ra m en to
, C al ifo
P rn ia rizo ho en ix
, A
D en ve r, na
C ol or ad o
Iq ui to s,
P er u
M ob ile
, A la
W in ni ba m a pe g,
C an ad a
Fa irb an ks
, A la sk a
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City E
1. Sacramento, California
2. Phoenix, Arizona
3. Denver, Colorado
47%
4. Iquitos, Peru
20%
5. Mobile, Alabama
13%
9% 6. Winnipeg, Canada
7%
4%
0% 7. Fairbanks, Alaska
S ac ra m en to
, C al ifo
P rn ia rizo ho en ix
, A
D en ve r, na
C ol or ad o
Iq ui to s,
P er u
M ob ile
, A la
W in ni ba m a pe g,
C an ad a
Fa irb an ks
, A la sk a
MET 112 Global Climate Change
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City F
1. Sacramento, California
2. Phoenix, Arizona
3. Denver, Colorado
83%
4. Iquitos, Peru
5. Mobile, Alabama
6. Winnipeg, Canada
5% 5% 5%
0%
2%
0% 7. Fairbanks, Alaska
S ac ra m en to
, C al ifo
P rn ia rizo ho en ix
, A
D en ve r, na
C ol or ad o
Iq ui to s,
P er u
M ob ile
, A la
W in ni ba m a pe g,
C an ad a
Fa irb an ks
, A la sk a
MET 112 Global Climate Change
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