Transcript Climate Literacy

Understanding Climate Change
MAST
October 22, 2010
Mort Sternheim [email protected]
Rob Snyder [email protected]
STEM Education Institute
University of Massachusetts Amherst
The Context for Climate Change Education
Is Earth’s temperature rising?
If so, how much are temperatures rising?
If so, why are temperatures rising?
http://www.arctic.noaa.gov/detect/global-temps.shtml
Factors that influence Earth’s climate include:
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Solar Activity.
The eccentricity of Earth’s orbit.
The tilt of Earth’s axis
Volcanic eruptions.
Earth’s albedo.
Atmospheric composition.
Ocean variability.
Climate change education provides opportunities for teachers
to meet state and national science learning standards.
Examples of Massachusetts Science and Technology/Enginneering Framework
learning standards include:
• Identify ways in which ecosystems have changed throughout geologic time in
response to physical conditions, interactions among organisms, and the actions
of humans. Life Science; Grades 6-8 (Page 53).
• Describe the effects on the environment and on the carbon cycle of using both
renewable and nonrenewable sources of energy. Earth and Space Science; High
School (Page 34).
• Analyze changes in population size and biodiversity that results from natural
causes, changes in climate, human activity, and the introduction of invasive,
non-native species; Biology High School (Page 56).
However, it is very important to understand that knowledge and
inquiry skills developed in each of the sciences contributes to
climate literacy.
An Example of a Climate Literacy Resource
Each essential principle in Climate Literacy: A Guide for Individuals and
Communities is supported by fundamental concepts comparable to those
underlying the National Science Education Standards and the AAAS
Benchmark for Science Literacy.
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A climate-literate person:
understands the essential principles of Earth’s climate
system.
knows how to assess scientifically credible information
about climate.
communicates about climate and climate change in a
meaningful way and
is able to make informed and responsible decisions
with regard to actions that may affect climate
http://www.globalchange.gov/resources/educators/climate-literacy
Climate Change Education Also Provides
Opportunities for Students To:
1. Develop Spatial Thinking
 Interpret maps, diagrams, graphs, charts, animations and
models.
2. Develop Temporal Thinking
 Understand how the history of climate change is
discovered and future changes predicted.
3. Understand Earth as a Complex System
 Explore feedbacks that occur between and among
components of Earth’s Climate System.
4. Learn in the Field
 Collect and analyze real time data and observations.
How Geoscientists Think and Learn, Kastens et al., EOS,Transactions,
American Geophysical Union; August 4, 2009, p. 265
1. Examples of spatial thinking questions
associated with climate change education
• Why does Earth’s rotation, axial tilt and orbital
motion result in seasonal changes in lengths
of daytime and the angle of incidence of
sunlight?
• How might changes in the Earth’s orbit and
axial tilt influence Earth’s natural climate
cycles?
For many students, diagrams have limited value
illustrating why the seasonal change
http://okfirst.mesonet.org/train/meteorology/Seasons.html
Today’s “midday” altitude at 11:36 AM of the sun
in the Boxborough area is 36.6°.
(Sunrise was at 6:10 AM. Sunset will be at 4:50 PM.)
gnomon
sun altitude angle
θ
Sun shadow of the gnomon
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http://www.usno.navy.mil/USNO/astronomical-applications/data-services/alt-az-us
A “Globe Walk”
A model of the Earth/Sun system daily and seasonal
changes in the angles of incidence of sunlight.
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Put a model of the sun in the center of the room.
Move a model Earth to its position in orbit for today’s date.
Locate a point on Earth for Boxborough (42.5°N).
Rotate Boxborough to midday.
Use a straw to point from Boxborough to the model sun.
Use another straw to point from Boxborough to a point south
of Boxborough.
• Measure the angle formed by the two straws.
The Globe Walk can also demonstrate seasonal changes
in the length of daytime.
Natural Climate Cycles
Milutin Milankovitch is credited with
formulating a theory that describes one cause
of climate change. His theory stated that
Earth’s axial tilt and orbital eccentricity
influenced Earth’s climate. His theory can be
explored using the “Globe Walk.”
http://en.wikipedia.org/wiki/Milankovitch_cycles
The Holocene Epoch began about 12,000 years ago. The
result was the end of the most recent ice age.
The early Holocene warming was
due principally to orbital changes as
suggested by the Milankovitch
Theory.
Note: the differences between
aphelion and perihelion distances
are greatly exaggerated in these
diagrams.
2. Examples of temporal thinking questions
associated with climate change education.
• How do we “go back in time” to construct a long
term history of CO2 levels in the atmosphere?
• How do those ancient levels of CO2 compare with
present day concentrations?
• How can we infer the long term history of Earth’s
temperature using stable isotopes of oxygen?
• Is there a connections between the pattern of
change in CO2 levels and the pattern of changes in
Earth’s temperatures?
Climate Scientists have been collecting data to construct a recent
history of CO2 concentrations in the atmosphere.
This NOAA web site explains how data for this graph was collected.
http://www.esrl.noaa.gov/gmd/ccgg/trends/
Climate scientists drill deep into an ice sheet to study
Earth’s ancient atmosphere in trapped air bubble and
water molecules in the ice.
http://researchnews.osu.edu/archive/lonthmppics.htm
The concentration of CO2 (and other gases) in air
bubbles trapped in deep layers of ice reveals the
concentrations of greenhouse gases in ancient Earth’s
atmosphere.
Climate scientists use ice core data to develop an understanding
of the relationship between CO2 concentrations and Earth’s
temperature cycles.
http://www.epa.gov/climatechange/science/pastcc.html
Earth’s temperature history can be inferred from ratios of stable isotope in
water molecules in layers snow and ice at higher latitudes
Evaporates more readily
16
O
1
1
H
H
18
O
1
H
Condenses more readily
1
H
• A mass spectrometer determines the ratio of oxygen isotopes in an air
bubble in an ice core.
• During cold periods on Earth, the concentration of more massive and
thus less volatile 2H and 18 O in the ice is lower than during warm periods.
• During warmer periods, water containing more massive isotopes can
reach higher latitudes. This increases the proportions of 2H and 18 O in the
ice.
3. Complex system questions associated
with climate change education
• How do positive and negative feedbacks either
amplify or diminish climate change?
• How do plants and animals respond to the
results of positive and negative feedback in
Earth’s climate system?
Climate Feedback Mechanisms
Positive Feedback: Melting snow and ice reveals darker land
and water surfaces that were beneath the snow and ice.
Darker surfaces absorb more of the Sun’s energy which causes
more melting in a self reinforcing cycle. This positive feedback
loop, known as the ‘ice-albedo feedback’, amplifies the
warming of the atmosphere.
Negative Feedback: Increased evaporation of water from
warmer oceans could result in an increase in cloud cover. The
increased cloud cover would reflect more incoming sunlight.
This negative feedback loop would diminish the warming of
the atmosphere. (However, the water vapor itself is a
greenhouse gas, and this offsets the increasing cloud cover.)
The most dramatic temperature changes are
occurring in the Arctic region.
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Warmer and dryer inland summers.
Rapid changes in animal habitats.
The influx of invasive plant species.
A drying up of lakes and rivers.
A loss of spring ice melt.
A decrease in the late summer Arctic Ocean ice
(observed by remote sensing).
Note: 40% of the world’s population relies on supplies of high
latitude and high elevation snow and ice for their fresh water.
August Arctic Ocean Ice Extent
Source: NSIDC
Students can construct a model of a remote sensing
satellite to study an “Arctic landscape.”
• For example: they can use colored papers to model
transitions from ice to bare ground to vegetation.
The LED in the model satellite transforms different
colors that it receives into electrical signals
Paper Color
Trial #1
(millivolts)
Trial #2
(millivolts)
red
8.0
8.1
orange
11.5
11.2
yellow
10.7
10.4
green
3.7
3.7
blue
3.4
3.3
black
2.6
2.3
white
10.4
10.2
This graph indicates changes intensities of red, green,
and blue light detected by the camera (along a line
across the digital photograph of the “landscape”).
Analyzing Digital Images, http://www.lawrencehallofscience.org/gss/rev/ip/
4. Examples of Field Experiences
Students can:
• Measure albedo and the associated warming effects.
• Use a gnomon and its shadow to monitor changes in
the angle of incidence of sunlight.
• Monitor the budding of plants in the spring.
• Collect temperature and precipitation data and
compare their data with data published in daily
newspapers and on NOAA websites.
Measuring albedo
• Three ways to measure albedo
– Light meters. Point down, up,
find the ratio.
– LED’s and multimeters. (An LED
can detect light as well as emit
it.) Same idea as light meter.
– Digital camera and free ImageJ
software. Compare brightness
of Xerox paper vs snow, turf,
pavement ….
• Mastech Digital 4Range 200,000 Lux
Luxmeter , $55
(Amazon.com)
Surface color, angle of incidence and
temperature change
• Measure effects of
albedo
– Temperature changes of
light and dark materials
exposed to heat lamps
– Measure temperatures
of soil, turf, concrete,
asphalt, …
• Measure effects of angle of
incidence
Two Common Climate Change Educational Issues
• Concerns some students may have about their future
Many web sites provide examples of actions for
individuals and communities that reduce the impact of human
activity on climate change.
• The skepticism that some students have about climate change
A study of albedo, remote sensing, Earth’s seasons, and
other aspects of climate science can be studied independently
of the issue of climate change.
Climate Change Education
at UMass Amherst
The Science, Technology, Engineering and
Mathematics Education Institute (STEM Ed)
and the Climate System Research Center
(CSRC) have developed a wide range of
climate change education curriculum
materials and presentations.
They are available at:
www.umassk12.net/ipy