SEV2a Natural Climate Change

Natural Climate Change

SEV2. Obtain, evaluate, and communicate information to construct explanations of stability and change in Earth’s ecosystems.

a. Analyze and interpret data related to short-term and long-term natural cyclic fluctuations associated with climate change. 

(Clarification statement: Short-term examples include but are not limited to El Niño and volcanism. Long-term examples include but are not limited to variations in Earth’s orbit such as Milankovitch cycles.)

Natural Climate Change

Weather or Climate

Short-Term Environmental Change

Long term Environmental Change

Cyclical fluctuations

ENSO, El Niño and La Niña

Volcanism

Milankovitch cycles

Continental Drift

Plate Tectonics

Multiple Choice

These multiple sources (rain fall, lake levels and satellite data) are averaged to measure changes in:

• Climate
• Weather

Multiple Choice

Blizzards, Heatwaves, High winds are all examples of __________________ events.

• Climate
• Weather

Multiple Choice

Which of these best describes climate rather than weather?

• Wind speed is changing as a storm moves through an area.

• The temperature is decreasing in a slow-moving cold front.

• Annual high temperatuers in the summer have increased over many decades.

• The rainfall during one year was greater than the rainfall during the next year.

Short-Term

Environmental

Changes

Short-term environmental changes, like
droughts, floods, and fires do not give
populations time to evolve to the change
and force them to move or become
extinct.

These changes typically occur over days to
hundreds of years.

Here are some examples of short-term
environmental changes.

Multiple Choice

What timeframe do short-term environmental changes take place over?

• days to weeks

• days to centuries

• weeks to centuries

• days to thousands of years

Volcanoes emit sulfur
dioxide and ash.

The ash blocks sunlight
and cools the earth.

The sulfur dioxide is
heated by the sun in the
atmosphere and becomes
sulfuric acid. The sulfuric
acid also blocks sunlight
and cools the earth.

These effects can last
from 1 - 3 years.

Multiple Choice

What is the main effect of volcanic eruptions on the climate?

• Long-term warming

• Short-term cooling

• Increased precipitation

• Enhanced greenhouse effect

Multiple Choice

Which gas released during volcanic eruptions has a cooling effect on the climate?

• Carbon dioxide (CO2)

• Sulfur dioxide (SO2)

• Methane (CH4)

• Nitrous oxide (N2O)

Multiple Choice

How long does a volcanic eruption affect the climate?

• 2-3 months

• 100-200 years

• 1-2 weeks

• 1-3 years

What looks different about this map?

Why is it important?

The Pacific is the largest ocean on the planet, so a significant change in its surface temperatures lead to changes in atmospheric winds. This can affect temperature, rainfall and vegetation in faraway places.

In normal years, trade winds push warm water, and its heavier rainfall, west to Indonesia. The warmer waters in the west and relatively colder waters in the east Pacific reinforce the pattern and strength of the trade winds.

Multiple Choice

What does the term ENSO refer to?

• El Nine/ Nothern Oscillation

• Enchiladas Not Sweetened Horita

• La Nina/ Southern Oscillation

• El Niño/ Southern Oscillation

ENSO

Today we are looking at
short term climate change
caused by cyclical
fluctuations in the Pacific
Ocean’s surface temps that
impact weather all over the
globe. They are called El
Niño and La Niña.

Multiple Choice

What is the El Niño-La Niña cycle?

• A cycle of volcanic eruptions

• A cycle of ocean acidification

• A cycle of sea level rise

• A cycle of sea surface temperature changes

What is El Niño

It is the occasional warming of the
eastern and central Pacific Ocean
around the equator. The warmer water
tends to get only 1 to 3 degrees
Celsius above the average
sea-surface temperatures for that
area, although in the very strong El
Niño of 1997-98, it reached 5 degrees
or more above average in some
locations.

A change of 3 degrees Celsius
corresponds to a change of 5.4
degrees Fahrenheit.

Multiple Choice

Is El Niño a short-term or long-term environmental change?

• Short-term. It lasts a year or two before fluctuating back to a normal year.

• Short-term. It lasts for a decade before changing back to a normal year.

• Long-term. It lasts a year or two before fluctuating back to a normal year.

• Long-term. It lasts for a thousand years before changing back to normal.el nino

Multiple Choice

What is the effect of La Niña on sea surface temperature?

• It causes a rise in temperature

• It has no impact on temperature

• It leads to a decrease in temperature

• It results in extreme temperature fluctuations

Surface Currents

We know surface currents change during ENSO.
Look carefully at how the air currents change and the changes that makes to where it rains.

Storms change location, droughts and floods can occur, fish can move to different locations, and agriculture is also affected.

Multiple Choice

Which phenomenon increases global temperature during the El Niño phase?

• Warmer water and heavier rainfall

• Cooler water and drought conditions

• Neutral sea surface temperature

• Increased ocean acidification

Study this map showing
the expected effects of El
Niño and La Niña.

Find Georgia on the map. What happens to our weather during ENSO?

ENSO Weather

Multiple Choice

Which Georgia weather conditions are associated with El Niño?

• increased temperature, increased precipitation
• decreased temperature, increased precipitation
• increased temperature, decreased precipitation
• decreased temperature, decreased precipitation

Multiple Choice

During an El Niño year, there is increased precipitation in the Southern United States, but the north is warmer and dry. Where does the moisture causing the precipitation in the South come from?

• the Pacific Ocean

• the Gulf of Mexico

• the polar jet stream

• the southern Atlantic OceanUS wea

Long-Term

Environmental

Change

Long-term environmental
change takes place over
thousands to hundreds of
thousands of years.

Remember that the Earth is
4.5 billion years old and
100-200 years are short-term
when compared to the age of
the Earth.

Evolution and

Adaptation

Long-term environmental
changes to our climate
happen so slowly that
populations are able to
evolve and adapt to the
changing climate.

When the climate changes
too fast, populations do not
have enough time to evolve
and many go extinct.

Milankovitch Cycles

Milankovitch
hypothesized that
changes in Earth’s
position as it orbits
the sun affects the
amount of solar
radiation that enters
our atmosphere
causing changes in
Earth’s climate.

Multiple Choice

What are Milankovitch cycles?

• Cycles of volcanic eruptions

• Cycles of ocean current changes

• Cycles of Earth's orbital changes

• Cycles of atmospheric temperature variations

Glacial periods on Earth
happen very regularly. This
matches the Milankovitch
Cycles. These changes
affect the advance and
retreat of glaciers

These cycles change
when and where the sun’s
heat hits the earth. It
doesn’t change the
amount of solar energy.

Multiple Choice

What is the impact of Earth's orbital changes on climate?

• They cause rapid climate fluctuations

• They lead to long-term cooling

• They trigger ice ages

• They have no significant impact on climate

Earth has changed over it's lifetime.

Why do the continents move?

They sit on top of plates that slide over
the liquid rock inside
the earth.

This is called Continental Drift. The
changes can affect ocean currents by altering the shape of ocean basins. This change in shape can redirect the flow of currents, creating new patterns and altering existing ones.

Multiple Choice

How do continental drift changes affect ocean currents?

• They have no impact on ocean currents

• They cause changes in wind patterns

• They alter the shape of ocean basins

• They lead to increased precipitation

Remember that oceans absorb a lot of heat and play a big role in precipitation amounts.

Areas around the coast typically experience milder seasons and more precipitation.

As the continents
shifted, so did the
climate.

Multiple Choice

What is the role of ocean currents in the climate system?

• They regulate atmospheric temperature

• They cause volcanic eruptions

• They control solar variations

• They distribute heat energy and regulate weather

Multiple Choice

What is the average duration of the El Niño-La Niña cycle?

• A few months

• A few years

• A few decades

• A few centuries

Multiple Choice

What are some natural causes of climate change?

• Human activities, volcanic eruptions, and ocean currents

• Solar variations, internal variability, and continental drift

• Earth's orbital changes, volcanic eruptions, and ocean currents

• Ocean currents, solar variations, and human activities