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Chapter 14
Weather Vs. Climate Weather: Conditions of the
atmosphere at a particular time
and place, for short periods of
time (days).
Climate: Long-term averages of
weather (Averaged over 30 yrs).
Weather Vs. Climate Example: What is the current weather in Benton County?
How would you describe the climate of Benton
County?
Factors Which Create Climate Zones
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Factors Which Create Climate Zones
Many factors affect climate:
1. The Sun
Radiation given off by the Sun.
Latitude affects amount of radiation
received.
Solar radiation absorbed or
reflected.
The Sun
Factors Which Create Climate Zones
2. Volcanic Eruptions
Factors Which Create Climate Zones
3. Elevation (mountains)
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Factors Which Create Climate Zones
4. Large bodies of water
(oceans)
Coastline vs. inland
Ocean currents
Factors Which Create Climate Zones
5. Global Wind Patterns
#1 Sun: Radiation Given Off by the Sun
The amount of radiation given
off by the Sun varies.
Sunspots = “Storms” that erupt
and send solar flares and
energy into space.
11-year cycle (solar min-max)
#1 Sun: Radiation Given Off by the Sun
Many sunspots = warmer temp.
Few sunspots = colder temp.
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#2 Sun: Effect of Latitude The further you travel from the equator, the colder it gets. Why?
The Sun’s radiation hits higher latitudes less direct.
Equator has DIRECT rays.
Poles have INDIRECT rays.
#2 Sun: Effect of Latitude Because the Earth is tilted:
During part of the year, each
pole receives no sunlight.
Polar Night ~ 6 Months!
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#3 Sun: Solar radiation absorbed or reflected
Earth’s surface features
determine if radiation is
REFLECTED or absorbed.
The poles are cold not only
because of their latitude, but
also because ice reflects much
of the incoming radiation.
#3 Sun: Solar radiation absorbed or reflected Feedback Loops Positive Feedback Loop:
Exaggerates and makes
changes more extreme
Negative Feedback Loop:
Brings systems back to normal
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Feedback Loops Ice Age Positive Feedback Loop
Low Sunspot Activity = lower
temperatures.
Low Temp = more ice and snow
Ice and snow reflect more solar
radiation
Temperature gets even colder.
2. Volcanic Eruptions Large eruptions release
aerosols into atmosphere
Aerosols = small particles.
Aerosols block solar radiation
and cause short-time cooling
for up to a few years.
2. Volcanic Eruptions
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3. Elevation (Mountains) Mountain climates are cooler,
as atmospheric temperature
decreases with altitude.
High elevations may allow snow
to form in the tropics.
One side of the mountain is
drier than the other.
3. Elevation (Mountains)
Inland Vs. Coastal Temperature
Find Indiana. What is the
average minimum temperature?
Travel to the east or west coast
at the same latitude. What is
the average minimum
temperature?
Inland Vs. Coastal Temperature
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Inland Vs. Coastal Temperature
Places of the same latitude
should receive the same
amount of solar radiation.
What might explain this
difference in temperature?
A. Coastline Climate Vs. Inland
Water heats and cools slower
than land. (doesn’t get as cold
in the winter, or as hot in the
summer)
Coastline cities are “insulated”
by the breeze coming off the
water.
A. Coastline Climate Vs. Inland
Coastline cities have more
“moderate” climate.
Inland cities have more extreme
climate (hotter in the summer,
colder in the winter) than inland
cities.
Inland Vs. Coastal Temperature
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B. Ocean Currents
Ocean currents circulate
Earth’s heat energy.
The effect of ocean currents on
climate depends on the
direction of the current.
B. Ocean Currents
From Equator, warm water is
moved towards the poles.
From poles, cold water is
moved towards the Equator.
B. Ocean Currents B. Ocean Currents
From Equator, warm water is
moved towards the poles.
From poles, cold water is
moved towards the Equator.
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5. Latitude and Global Wind Global wind patterns affect
precipitation.
Much rain & rainforests at low latitudes.
Little rain & deserts at 30 Lat.
Mid-latitudes: Our weather comes from the west.
Tropical: Hurricanes come from the east.
5. Latitude and Global Wind 5. Latitude and Global Wind Global wind patterns affect
precipitation.
Much rain & rainforests at low latitudes.
Little rain & deserts at 30 Lat.
Mid-latitudes: Our weather comes from the west.
Tropical: Hurricanes come from the east.
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14.2: Climate Classifications
Climates are classified based
on three main characteristic
1. Temperature: monthly and
annual averages
2. Precipitation patterns
3. Vegetation
Tropical Moist Climates
Year-round average
temperature above 67F (18C)
Located between 23.5N and
23.5S latitude.
Direct solar radiation all year.
Lots of clouds and rain.
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Dry Climates
Low/deficient precipitation
annually.
Found at 30N and 30S latitude
Dry Climates
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Mid-Latitude Climates
Mild Winters
30-60N to 30-60S
Oceans “insulate”: More stable temperatures.
Cold Winters
30-60N to 30-60S
Inland, middle of continent
Polar Climates
60-90N to 60-90S
Extremely cold winters and
summers due to indirect
sunlight.
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Four Sphere System
Earth can be divided into 4 systems that each have a specific role.
Lithosphere
Hydrosphere
Biosphere
Atmosphere
Lithosphere
What makes up the lithosphere?
(List 4 components)
Rocks
Minerals
Volcanoes
Fossil Fuels
Lithosphere
What are the major occurrences
in the lithosphere?
The Rock Cycle
Plate Tectonics
Earthquakes
Volcanoes
Lithosphere
When decomposing organic
matter in sediments is subjected
to intense heat and pressure,
what does it turn into?
Coal, petroleum, natural gas.
(Carbon sources)
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Hydrosphere
How much of the Earth is covered by
water?
What is water in the atmosphere
called?
What happens when water vapor in
the atmosphere cools?
Hydrosphere
Biosphere List 4 examples of parts of the biosphere:
Plants, Animals, Fungi, Bacteria…
What cycles outside of the biosphere are
important for living things?
The water cycle
The nitrogen cycle
The carbon cycle
The phosphorus cycle
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Consider the Following:
Where does the oxygen plants produce come from?
Atmosphere What two main gasses make up 99% of the air in the
atmosphere?
Nitrogen: 78% Oxygen: 21%
What are 3 major greenhouse gasses?
Carbon Dioxide (CO2)
Methane (CH4)
Water Vapor (H2O)
Greenhouse gasses therefore make up less than 1% of the total gasses in the atmosphere.
The Carbon Cycle Most of Earth’s carbon—about 65,500
billion metric tons—is stored in rocks. The rest is in the ocean, atmosphere, plants, soil, and fossil fuels.
What is a hydrocarbon? Where are most found?
In what form is carbon found in the oceans?
Calcium Carbonate (CaCO3) and Carbon Dioxide (CO2)
Hydrocarbons
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Hydrocarbons Hydrocarbons
The Carbon Cycle In what form is carbon found in the biosphere?
Sugars, Protein, Methane (CH4)
In what form is carbon found in the atmosphere?
Carbon Dioxide and Methane
Which sphere of Earth contains the least amount of Carbon?
The atmosphere.
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Sources of Greenhouse Gases Carbon Dioxide: CO2
There are 4 main greenhouse gases: CO2, CH4, N2O, and H2O
Today, only 5% of CO2 in the atmosphere comes from natural processes such as cellular respiration.
95% of ATMOSPHERIC CO2 comes from human activity, such as combustion.
Most abundant human caused GHG
Sources of Greenhouse Gases Methane: CH4
Compared to CO2, there is much less CH4 in the atmosphere.
BUT, it can trap 20x more heat than CO2.
YET, it has a short lifespan and breaks down with time.
Sources: Livestock digestion, landfill waste, burning fossil fuel.
Sources of Greenhouse Gases Nitrous Oxide: N2O
Only a small amount in the atmosphere.
BUT, it can trap 300x more heat in than CO2
Natural Sources: Soil and ocean release N2O into the atmosphere.
Human Sources: Agriculture, fuel combustion in motor vehicles.
Sources of Greenhouse Gases Water Vapor: H2O
Most abundant GHG in the atmosphere.
Has the biggest impact on temperature compared to all the other GHGs
Traps 2/3rds of all the heat trapped by the atmosphere.
Water vapor is in constant flux between the hydrosphere, atmosphere, and biosphere.
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Sources of Greenhouse Gases Water Vapor: H2O
Changes in its movement between these systems could have a significant impact on the warming and cooling of the atmosphere.
Yet, water vapor levels have been constant throughout history, so it does not appear to be responsible for the warming Earth is undergoing.
Greenhouse Effect Vs. Global Warming
Greenhouse Effect
Traps just enough heat to keep Earth at a habitable temperature.
We NEED the greenhouse effect
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Greenhouse Effect Vs. Global Warming Global Warming
Increase in Earth’s global temperatures BEYOND the Greenhouse Effect.
Primarily due to increased CO2 levels due to humans burning fossil fuels.
Since the Industrial Revolution, CO2 levels have increased 41%
Climate Change Positive and Negative Feedback Loops
Positive Feedback: Global Warming Negative Feedback?: Global Warming
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Consider the Following
What affect does global warming have on the oceans?
Global Warming Debate
There is no debate among scientists that climate change is occurring.
• The only debates scientists are having are about the potential outcomes.
• Predictions are difficult to make because climate is affected by many factors.
Global Warming Debate
Scientists are unable to directly test climate in the laboratory.
Relies on computer simulations to make predictions.
Global Warming Debate
The Debate:
Which of the following will increasing water vapor create?
"Everyone agrees that if you add carbon dioxide to the atmosphere, then warming will result, So the real question is, how much warming?“ –Andrew Dessler (Texas A&M)
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What will happen?
Positive Feedback: Increasing H2O vapor will trap
more heat and warming will continue
Negative Feedback: Increasing H2O vapor will create
clouds and block the Sun causing temperatures to stabilize.
Effects of Climate Change
There are direct correlations between an increase in greenhouse gases and: 1. Global temperature changes 2. Sea level changes 3. Weather event frequency
changes 4. Ocean acidification changes
Temperature Change
Both land and ocean temperatures are increasing
Land temperatures are increasing faster than water. Why?
Water has a higher specific heat:
the heat required to raise the temperature of a given substance by a given amount
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Temperature Change
More heat waves affecting mid-latitudes (Indiana)
Summer 2016 was one of hottest on record in the lower 48 states.
Every state was above average for temperature.
Temperature Change
Temperature Change
The amount of sea ice, glaciers, and permafrost has decreased due to melting.
Sea Ice Minimum 1984 Vs. 2012
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Temperature Change
Sea Level Change
Sea level has risen worldwide ~ 20cm since the 1960’s.
As oceans warm, the water molecules move faster, and the water expands. (volume increases)
Melting glaciers and ice sheets release more water.
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Weather Event Frequency Changes
• Increase in frequency of extreme weather events:
• Drought, hurricanes, flooding, blizzards
• Mid-latitude changes:
• Increase in rain in the winter and/or heavy snowfall
Weather Event Frequency Changes
Mediterranean & Africa:
Droughts have increased
Hurricanes:
Increased hurricane intensity and strength due to warmer oceans (not frequency!)
Move further towards poles before stopping. (pushing further N up the east coast)
Ocean Acidification Changes
Oceans are natural reservoirs for Carbon Dioxide (CO2).
As CO2 is absorbed, the oceans become more acidic (carbonic acid)
Effects: formation of coral, shells, crabs, snails, clams, affecting the entire reef system.
Ocean Acidification Changes
Oceans will NOT be able to continue absorbing CO2 at the rates it is being added.
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Effects of Climate Change on Agriculture Strategies to Limit Climate Change
Strategies are aimed at reducing atmospheric CO2
Clean Energy
(Wind, Solar, Geothermal)
International Awareness (Paris Agreement)
Developing Vs. Developed Nations
Developing:
Have less money to pay for the controls needed.
Money spent to limit GHGs would put their country in poverty.
Argue that developed countries caused climate change – developed nations should be the ones to pay.
Developed Vs. Developing Nations
Developed:
Think developing nations would have an economic advantage if they don’t have to follow the same regulations.
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Developed Vs. Developing Nations
Personal Awareness
What is your “carbon footprint”? How can you decrease it?
(Check out the link on the class website!)
Upwelling
Upward motion of ocean water.
Cold because it originates at the bottom of the ocean.
Usually occurs on the west coast of continents in the area of trade winds.
Upwelling
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Upwelling
Rich in nutrients
Supports abundant marine life
Good fishing off of Peru and California.
El Niño: Defined Unusually warm ocean water
off the west coast of South America
Equatorial winds blowing from West to East (opposite of normal equatorial winds)
Pushes hot moist air and water east towards N. and S. America
El Niño: Effects on Climate
Causes NW coast of South America to be warmer and wetter than normal.
Little upwelling – Commercial fishing suffers.
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El Niño: Effects on U.S.
Brings winter storms to California and SW U.S.
Warmer winter for entire US, including Indiana(dry).
Benefits: Upper winds prevent hurricane formation in the SE
La Niña: Defined
Unusually cold ocean water off the west coast of South America
Equatorial winds blowing stronger than normal from East to West
Pushes hot moist air and water away from N and S America
La Niña: Effects on Climate Can cause droughts to the
southern U.S.
Brings cooler temperatures and heavy precipitation to the pacific Northwest
Cold air pushes south and brings lake effect snow to Indiana.
