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Climate and climate change
Weather: The state of the atmosphere at a particular
place at a particular moment.
Climate: The long term weather patterns of an area.
This is what gives us the average daily high and low
temps.
Six main factors that cause climate:
1. latitude:
The more distance from the equator = colder average
temperatures.
The lower the latitude the higher the angle of insolation.
The higher the angle the hotter the average
temperature.
Tropics: Area of latitude between 23.5degrees north and
South latitude.
Temperate zone: between 23.5 and 66.5 North and
South
Polar zone: Between 66.5 and 90 North and South
Latitude.
The number of day light hours varies greatly based on
latitude.
In the tropics there is no summer or winter and the
average amount of day light is 12 hours.
Half way between the poles at 45 degrees a summer
day can be as long as 16 hours and a winter day can be
as short as 8.
At 90 degrees, the day light can last 24 hours a day.
So why are the poles so much colder? The angle of
insolation (sun light) is much lower.
2. Atmosphereic circulation patterns:
Wind Belts: Winds that flow around the planet in a
given direction for a given latitude:
Ex: Prevailing westerlies drives storms in the U.S.
from the west to the east.
2. Atmosphereic circulation patterns:
Three important properties of air illustrate how air
circulation can affect climate:
1. Cold air sinks because it is more dense than
warm air. As it sinks it will compress and
warm.
2. Atmosphereic circulation
patterns:
2. Warm air rises. As it rises
it expands and cools.
3. Warm air can hold more
water vapor than cold air.
There for as the rising
warm air cools, the vapor
may condense and form
clouds and precipitation.
The air flow there for determines where it will be dry and
where it will be wet.
30 degrees where air flows apart (high pressure) = dry
0 degrees where air flows together (low pressure) = wet
2. Atmosphereic circulation patterns:
-Air masses: A large volume of air that has the
characteristics of temperature and humidity.
-Fronts: The leading edge of an air mass.
1. Cold
2. Warm
3. Occluded
4. Stationary
3. Oceanic circulation patterns:
Like the wind belts,the ocean currents also
redistribute heat.
Ex: The North Atlantic drift brings heat to Europe.
4. Local geography:
-Coastal areas are cooler in the summer and
warmer in the winter than inland regions (due to
the high specific heat of water).
4. Local geography:
-Climbing in altitude will decrease the
temperature
Orographic lifting
-Windward side of mountain is wet (ex Seattle)
-Leeward side of mountain is dry (rain shadow)
5. Solar activity:
The Sun has an 11 year
Sun Spot cycle.
The more Sun Spots =
warmer temperatures.
1. Solar activity can
vary. A decrease in
sunspot activity has been
linked to cooler
temperatures,
Maunder Minimum: From
1645-1716, few sun
spots were detected,
resulting in the “Little Ice
Age”
6. Volcanic activity and meteorite impacts:
Either event can throw a large amount of dust
and ash into the air which blocks and diminishes
the amount of Sun light that can reach the Earths
surface.
14.2 Climate Classification
Koeppen Classification system: Classifying climates
on the basis of temperature, amount of precipitation
and to a lesser extent types of vegetation.
14.2 Climate Classification
The following is a list of the various climates:
-Tropical: Warm and often wet
-Mild: Found near water and are humid
-Dry: More evaporation then precipitation
-Continental: 3 sub types, warm summer, cool
summer and sub arctic
-Polar: Passed the Continental climates 66.5
degrees North and south latitude.
-High elevation: A type of a micro climate (Local
climate different from main regional climate) where
you climb in elevation and it is colder
14.2 Climate Classification
MicroClimates: A localized climate that differs from
the main regional climate.
Heat Islands: The presence of many concrete
buildings and large expanses of asphalt can create
an area of higher temperatures. ex NYC is often 10
degrees warmer than it’s surrounding suburbs.
14.3 Climate Changes
Ice Ages: Period of extensive Glacial coverage
The last one ended 10,000 years ago
*Created most of the lakes in NY
This represented an average global drop in temp of 5 degrees
Featured below is the rare bionic penguin which moves really,
really fast.
14.3 Climate Changes
Short term Climatic Changes
Seasons: Caused by variations in sunlight both in duration and
angle. This is caused by the tilt of the Earth as it revolves
around the Sun. ***Some scientists have speculated that the
enormous penguin population in the South Pole has caused this
tilt. JK people, JK.
14.3 Climate Changes
We apologize for the notes on the previous page, those
responsible have been sacked.
El Nino: Warm ocean current that occasionally develops off
the western coast of South America. This can alter the normal
storm track and bring storms to Southern North America.
***No, really, a penguin once bit my sister, it was awful!
14.3 Climate Changes
We apologize for the notes on the previous page, those responsible for
sacking those responsible, have been indeed been sacked.
Changes can be natural:
1. Solar activity can vary. A decrease in sunspot activity
has been linked to cooler temperatures,
Maunder Minimum: From 1645-1716, few sun spots were
detected, resulting in the “Little Ice Age”
2. Earth’s orbit can change. In a 100,000 year cycle Earth’s
orbit goes from elliptical to circular (warmer temps to cooler
temps).
3. Earth’s Tilt varies: between 22.1-24.5 over 41,000 years
4. Earth’s Wobble: Over a period of 26,000 years, the Earth
changes its tilt direction. In about 14,000 our “north star”
will be Vega, not Polaris.
Volcanic Activity: Dust from explosions can cool temperatures
14.4 The Human Factor
The Greenhouse Effect:
When radiation from the sun is trapped in Earth’s atmosphere
by “Greenhouse gases” such as Carbon Dioxide
The Sunlight (short wave: more intense) is strong enough to go
through the atmosphere, but when reflected off of Earth’s
surface, turns into infra red (long wave: not intense) and can
not escape. This acts like a greenhouse in which the heat is
trapped inside. This activity can result in Global Warming. As
trees are cut down, this increase the amount of CO2 in the
atmosphere, and will speed up the process. The Ice caps could
melt, and flooding will occur. This would be very bad for
penguins.
1. Which is not a variable that greatly affects
climate?
A. Distance from the Sun
B. Topography
C. Air masses
D. Latitude
2. Which is not a variable that greatly effects
Long term climate change?
A Solar activity can vary
B. Earth’s orbit can change
C. Earth’s Tilt varies
D. Solar and lunar eclipses.
3. Which is not part of the Koeppen Classification
system?
A. Temperature
B. vegetation.
C. Amount of precipitation
D. Air
Currents
4. What happens to Sun light after it hits the
Earth?
A. It turns into infrared radiation
B. It is all reflected by the clouds
C. It is all absorbed by water
D. The ozone layer blocks all incoming radiation
***Bonus
Draw a diagram showing the concept of global
warming. Be sure to show a difference in the
wave length of the in-coming solar radiation vs
the out going radiation.