Weather

1
Weather
2
The Answer is blowing in the wind

• Earths Circulatory System
• Heats and cools
• Transports
• Is this a good thing?

3
In the troposphere

• temperature
• pressure
• humidity
• precipitation
• sunshine
• cloud cover
• wind direction
• wind speed

These properties change to at any given point in
time to produce weather
Climate vs. Weather?
4
Masses of Air Move

• warm or cold
• wet or dry
• high or low pressure

Movements causes weather changes

• Warm front
• less dense
• rises condenses
• clouds form and rainfall at lower altitudes

• Cold front
• more dense
• close to ground
• high winds thunderstorms

5
Atmospheric pressure changes weather
HIGH - cool, dense air drops to surface and warms
to produce fair weather LOW - warm, less dense
air spirals to center of mass air condenses to
produce heavy rainfall
LOW PRESSURE
HIGH PRESSURE
Heat released radiates to space
Condensation and precipitation
Cool, dry air
Rises, expands, cools
Falls, is compressed, warms
Flows toward low pressure, picks up moisture and
heat
Warm, dry air
Hot, wet air
Moist surface warmed by sun
6
Weather Extremes

• Tornadoes
• Hurricanes
• Typhoons (Pacific)
• Hurricanes (Atlantic)

Occur over land
Tropical Cyclones are like tornadoes that occur
over the ocean
Are there any benefits to these disasters?
7
Prince Williams Sound
Gulf of Alaska
Risk of Tornadoes
CANADA
Highest
High
Medium
UNITED STATES
Low
Grand Banks
Hurricane Frequency
High
Moderately high
Atlantic Ocean
MEXICO
8
Climate

• Temperature
• Precipitation
• Seasonal Variations
• Extreme weather potential

The general pattern of atmospheric or weather
conditions
Driven by planetary winds and ocean currents
9
Climate
is
the average weather patterns for an area over a
long period of time (30 - 1,000,000 years).
It is determined by
Average Temperature
and
Average Precipitation
which are influenced by
latitude
altitude
ocean currents
and affects
what they grow and eat
where people live
how people live
10
Regional Climates are affected by global winds

• Latitude longitude (equatorial effects)
• Tilt of Axis cause seasons

Are we closer to the sun during the summer?

• Rotation of Earth transfers heat and water from
  one area to another
• Fluctuations in Solar Output
• Properties of Air Water

11
Cold
Cool Temperate
Warm Temperate
Tropical
(equator)
Tropical
Warm Temperate
Cool Temperate
Cold
Fig. 6.6a, p. 125
Climate type
12
Easterlies (from the east)
Westerlies (from the west)
60N
Northeast tradewinds
30N
(Doldrums)
equator
Southeast tradewinds
Prevailing Winds!
30S
Westerlies
Easterlies
60S
Deflections in the paths of air flow near the
earths surface 
Initial pattern of air circulation
Fig. 6.6b, p. 125
13
Warm ocean current
Warm temperate
Highland
Polar (ice)
Cold ocean current
Dry
Major upwelling zones
Subarctic (snow)
Fig. 6.4, p. 124
River
Tropical
Cool temperate
14
Spring (sun aims directly at equator)
Winter (northern hemisphere tilts away from sun)
Solar radiation
Summer (northern hemisphere tilts toward sun)
Fig. 6.5, p. 124
Fall (sun aims directly at equator)
15
Regional Climates are affected by ocean currents

• Everything we just talked about currents are
  driven by winds rotation
• Density of water (Thermohaline effect - salt and
  temps)

What are some benefits of this ocean churning?
16
El Niño
Drought
Unusually high rainfall
Unusually warm periods
Fig. 6.11, p. 127
17
El Nino Southern Oscillation

• Westerlies weaken
• Surface water along N S Amiercan warms
• No normal upwellings

• Decline in populations of fish species
• Extreme weather conditions
• Unusually mild weather

18
Wind
Movement of surface water
Diving birds
Fish
Upwelling
Zooplankton
Phytoplankton
Nutrients
Fig. 6.9, p. 126
19
Surface winds blow westward
EQUATOR
SOUTH AMERICA
Warm waters pushed westward
AUSTRALIA
Warm water
Thermocline
Cold water
Normal Conditions
20
Winds weaken, causing updrafts and storms
Drought in Australia and Southeast Asia
EQUATOR
Warm water flow stopped or reversed
SOUTH AMERICA
AUSTRALIA
Warm water deepens off South America
Warm water
Thermocline
Cold water
El Niño Conditions
Fig. 6.10b, p. 127
21
El Nina

• Follows El Nino
• more Atlantic hurricanes
• colder winters
• more ppt in Pacific NW
• more rain in SE Asia
• more wildfires

22
Topography Affects Climate

• Microclimates - local climatic conditions
• Mountain ranges cool winds blowing inland - RAIN
  SHADOW

23
a Winds carry moisture inland from Pacific Ocean
b Clouds, rain on windward side of mountain range
c Rain shadow on leeward side of mountain range
4,000/75
3,000/85
2,000/25
1,800/125
1,000/25
Moist habitats
1,000/85
15/25
Fig. 6.14, p. 129
24
Vegetation Effects

• Releases water
• casts shadows
• changes movement of winds

Urban Effects

• Asphalt Concrete
• Buildings
• Cars

25
Cool air descends
Warm air ascends
Land warmer than sea breeze flows onshore
Fig. 6.15a, p. 130
26
Cool air descends
Warm air ascends
Land cooler than sea breeze flows offshore
Fig. 6.15b, p. 130
27
Cell 3 North
Cold, dry air falls
Moist air rises rain
Polar cap
Cell 2 North
Arctic tundra
Evergreen coniferous forest
60
Cool, dry air falls
Temperate deciduous forest and grassland
Cell 1 North
Desert
30
Moist air rises, cools, and releases moisture as
rain
Tropical deciduous forest
Tropical rain forest
0
Equator
Tropical deciduous forest
30
Cell 1 South
Desert
Temperate deciduous forest and grassland
Cool, dry air falls
60
Cell 2 South
Polar cap
Cold, dry air falls
Moist air rises rain
Fig. 6.8, p. 126
Cell 3 South
28
3
198283
199798
El Nino conditions
La Nina conditions
2
1
Temperature/Change (F)
0
-1
-2
1950
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
Year
Fig. 6.12, p. 128
29
(a)
(b)
(c)
Rays of sunlight penetrate the lower atmosphere
and warm the earth's surface.
The earth's surface absorbs much of the incoming
solar radiation and degrades it to
longer-wavelength infrared radiation (heat),
which rises into the lower atmosphere. Some of
this heat escapes into space and some is absorbed
by molecules of greenhouse gases and emitted as
infrared radiation, which warms the lower
atmosphere.
As concentrations of greenhouse gases rise,
their molecules absorb and emit more infrared
radiation, which adds more heat to the lower
atmosphere.
Fig. 6.13, p. 128
30
Tropic of Cancer
Equator
Tropic of Capricorn
Semidesert, arid grassland
Arctic tundra (polar grasslands)
Desert
Boreal forest (taiga), evergreen
coniferous forest (e.g., montane coniferous
forest)
Tropical rain forest, tropical evergreen forest
Mountains (complex zonation)
Temperate deciduous forest
Tropical deciduous forest
Ice
Temperate grassland
Tropical scrub forest
Fig. 6.16, p. 131
Dry woodlands and shrublands (chaparral)
Tropical savanna, thorn forest
31
Polar
Subpolar
Temperate
Desert
Tropical
Desert
Fig. 6.17, p. 132
32
Low
Alpine Tundra
Montane Coniferous Forest
Elevation
Deciduous Forest
Tropical Forest
High
Tropical Forest
Temperate Deciduous Forest
Northern Coniferous Forest
Arctic Tundra
Low
High
Moisture Availability
Fig. 6.18, p. 133
33
Fig. 6.19a, p. 133
Tropical desert (Saudi Arabia)
34
Fig. 6.19b, p. 133
Temperate desert (Reno, Nevada)
35
Fig. 6.19c, p. 133
Polar desert (northwest China)
36
Red-tailed hawk
Producer to primary consumer
Gambel's quail
Primary to secondary consumer
Yucca
Jack rabbit
Collared lizard
Secondary to higher-level consumer
All producers and consumers to decomposers
Fungi
Fig. 6.20, p. 134
37
Fig. 6.21a, p. 137
Tropical grassland (savanna) (Harare, Zimbabwe)
38
Fig. 6.21b, p. 137
Temperate grassland (Lawrence, Kansas)
39
Fig. 6.21c, p. 137
Polar grassland (arctic tundra) (Fort Yukon,
Alaska)
40
Cape buffalo
Wildebeest
Beisa oryx
Topi
Warthog
Thompson's gazelle
Waterbuck
Grant's zebra
Dry Grassland
Moist Grassland
Fig. 6.22a, p. 138
41
Giraffe
African elephant
Gerenuk
Black rhino
Dik-dik
East African eland
Blue duiker
Greater kudu
Bushbuck
Dry Thorn Scrub
Riverine Forest
Fig. 6.22b, p. 138
42
Golden eagle
Producer to primary consumer
Primary to secondary consumer
Secondary to higher-level consumer
All producers and consumers to decomposers
Prairie dog
Bacteria
Fungi
Fig. 6.23, p. 139
43
Long-tailed jaeger
Producer to primary consumer
Grizzly bear
Caribou
Primary to secondary consumer
Mosquito
Secondary to higher-level consumer
Arctic fox
Horned lark
All consumers and producers to decomposers
Lemming
Fig. 6.24, p. 140
44
Fig. 6.25, p. 141
45
Fig. 6.26a, p. 142
Tropical rain forest (Manaus, Brazil)
46
Fig. 6.26b, p. 142
Temperate deciduous forest (Nashville, Tennessee)
47
Polar evergreen coniferous forest (boreal
forest, taiga) (Moscow, Russia)
Fig. 6.26c, p. 142
48
Harpy eagle
Ocelot
Blue and gold macaw
Producer to primary consumer
Primary to secondary consumer
Squirrel monkeys
Climbing monstera palm
Secondary to higher-level consumer
Katydid
Green tree snake
All producers and consumers to decomposers
Tree frog
Ants
Bromeliad
Fig. 6.27, p. 143
Fungi
Bacteria
49
45
Emergent layer
Harpy eagle
40
35
Toco toucan
Canopy
30
Height (meters)
25
20
Wooly opossum
15
10
Shrub layer
Brazilian tapir
5
Black-crowned antpitta
0
Fig. 6.28, p. 144
50
Broad-winged hawk
Producer to primary consumer
Hairy woodpecker
Primary to secondary consumer
Gray squirrel
White oak
Secondary to higher-level consumer
White-footed mouse
White-tailed deer
All producers and consumers to decomposers
Shagbark hickory
Racer
Wood frog
Fungi
Fig. 6.29, p. 146
Bacteria
51
Blue jay
Producer to primary consumer
Primary to secondary consumer
Balsam fir
Secondary to higher-level consumer
Moose
Wolf
All producers and consumers to decomposers
Bebb willow
Snowshoe hare
Fungi
Starflower
Bunchberry
Fig. 6.30, p. 147
Bacteria
52
Fig. 6.31, p. 148