Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
6
Climate change
Objectives
1.
Students are able to explain the mechanisms of climate change
2.
Students are able to describe the consequences of climate change globally (this
comes from a film)
3.
Students are able to list the main gases and sectors causing climate change and
the countries that pollute more than others
4.
Students can describe how the climate is predicted to change in East
Africa/Tanzania
Materials needed
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Film: Climate change, the state of science https://www.youtube.com/watch?v=_EWOrZQ3L-c
Flip chart of the mechanism of climate change (greenhouse gasses trapping heat)
Flip chart of a pie chart showing the gasses that cause climate change
Flip chart to describe the sectors that contribute to climate change
Flip chart on the worst pollutants (countries)
Laminated pictures on the predicted rainfall and temperature changes in Tanzania
Leave to do task: Consequences of climate change in Tanzania.
What consequences do increased rainfall, raised temperature and unpredictable weather patterns
(droughts and heavy rains, missing rainy seasons) bring in Tanzania? Think especially about 1. urban
areas, 2. agriculture (cropping in highlands and lowlands and livestock keeping) and 3. infrastructure
(roads, bridges). Make lists in the exercise books. No materials needed for leave-to-do task.
Sequence of the lesson
List to the students the learning objectives as above
1. Define the concepts and give central background information. Elicit from
students as much as possible:
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Climate change is a significant and lasting change in the statistical distribution of weather
patterns over periods ranging from decades to millions of years. It may be a change in average
weather conditions, or in the distribution of weather around the average conditions.
How it is known to take place? Scientists actively work to understand past and future climate by
using observations and theoretical models.
The term is now often used to refer specifically to climate change caused by human activity, as
opposed to changes in climate that may have resulted as part of Earth's natural processes. In
this sense, especially in the context of environmental policy, the term climate change has
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Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
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become synonymous with anthropogenic global warming. (anthropogenic=produced by
humans)
Within scientific journals, global warming refers to surface temperature increases while climate
change includes global warming and everything else that increasing greenhouse gas levels will
affect.
The difference between weather and climate: Weather refers to the conditions at one
particular time and place, and can change from hour to hour, day to day, and season to season.
Climate, on the other hand, refers to the long-term (decades at least) average pattern of
weather in a place. Long-term data are needed to determine changes in climate.
Does ozone hole cause global warming? No. Ozone depletion is a different problem, caused
mainly by CFCs (like Freon) once used in refrigerators and air conditioners. In the past, CFCs
were also used in aerosol spray cans, but that use was banned in the 1970s. CFCs deplete the
stratospheric ozone layer that protects life on Earth from excess ultraviolet light that can cause
skin cancer and cataracts in humans and other damage to plants and animals. An international
agreement has phased out most uses of CFCs but the ozone layer is only just beginning to
recover, partly because these chemicals remain in the atmosphere for a long time.
The most authoritative source of information on climate change is the UN Intergovernmental
Panel on Climate Change (IPCC) which draws upon the collective wisdom of many hundreds of
scientists from around the world.
Describe the mechanism of global warming, i.e. the Green house effect
1. Sun shines to the earth and warms the
earth
2. Geenhouse gasses form a layer in the
atmosphere and hinder the passage of the Infra
red rays (warmth) back to the space
Picture from http://www.articlesbase.com/k-12-educationarticles/global-warming-and-mechanism-6291127.html
2. Show the film for the first time.
Then show the film for the second time and ask students to list all the consequences of climate
change mentioned on the film. Stop the film in-between to give them time to write.
Temperature raise, heat waves more often and last longer, Arctic will warm faster than global average,
sea ice will vanish for summer, sea level raise will accelerate (cities in coastal areas are vulnerable), in
general wet areas will get wetter and dry areas dryer, monsoons are likely to become longer, down
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Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
pours likely to intensify, acidity of the ocean has increased 26% since the start of the industrial
revolution.
3. What gases are greenhouse gasses, what sectors are the worst, which countries
are the biggest polluters ?
Certain gases that trap heat are building up in Earth's
atmosphere.
1. The primary culprit is carbon dioxide, released
from burning coal, oil and natural gas in power plants,
cars, factories, etc. (and to a lesser extent when forests
are cleared).
2. The second is methane, released from rice
paddies, both ends of cows, rotting garbage in landfills,
mining operations, and gas pipelines.
3. Third are chlorofluorocarbons (CFCs) and
similar chemicals, which are also implicated in the
separate problem of ozone depletion.
4. Nitrous oxide from fertilizers and other
chemicals.
Which human activities are the worst causes of
climate change?
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Energy Supply (26% of 2004 global
greenhouse gas emissions) - The burning of coal,
natural gas, and oil for electricity and heat is the
largest single source of global greenhouse gas
emissions.
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Industry (19%) - Greenhouse gas emissions
from industry primarily involve fossil fuels burned
on-site at facilities for energy. This sector also
includes emissions from chemical, metallurgical,
and mineral transformation processes not
associated with energy consumption.
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Land Use, Land-Use Change, and
Forestry (17%) - Greenhouse gas emissions from
this sector primarily include carbon dioxide (CO2)
emissions from deforestation, land clearing for agriculture, and fires or decay of peat
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Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
soils. This estimate does not include the CO2 that ecosystems remove from the
atmosphere. The amount of CO2 that is removed is subject to large uncertainty,
although recent estimates indicate that on a global scale, ecosystems on land remove
about twice as much CO2 as is lost by deforestation.
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Agriculture (14%) - global greenhouse gas emissions) - Greenhouse gas emissions
from agriculture mostly come from the management of agricultural soils, livestock,
rice production, and biomass burning.
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Transportation (13%) - Greenhouse gas emissions from this sector primarily involve
fossil fuels burned for road, rail, air, and marine transportation. Almost all (95%) of
the world's transportation energy comes from petroleum-based fuels, largely gasoline
and diesel.
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Commercial and Residential Buildings (8%) - Greenhouse gas emissions from this
sector arise from on-site energy generation and burning fuels for heat in buildings or
cooking in homes. (Note: Emissions from electricity use are excluded and are instead
covered in the Energy Supply sector.)
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Waste and Wastewater (3%) - The largest source of greenhouse gas emissions in this
sector is landfill methane (CH4), followed by wastewater methane (CH4) and nitrous
oxide (N2O). Incineration of some waste products that were made with fossil fuels,
such as plastics and synthetic textiles, also results in minor emissions of CO 2.
Who are the big polluters?
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Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
4. Does anyone know how the climate is predicted to change in Tanzania?
Rainfall?
All climate prediction models agree that rainfall will increase in Tanzania or will not change.
Unpredictability will increase (floods, droughts). Show the laminated pictures.
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Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
How does the temperature change in Tanzania?
All climate prediction models agree that temperature will increase. Show the laminated
pictures.
http://www.ifpri.org/publication/east-african-agriculture-and-climate-change0http://hdgc.epp.cmu.edu/teachersguide/teachersguide.htm
http://www.epa.gov/climatechange/ghgemissions/global.html
Introduce the ‘leave-to-do task’.
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Environmental Science Clubs in Mwanga, Tanzania
Liana, 2014 (www.liana-ry.org)
Introduction to the Nature club teacher
Consequences of climate change in Tanzania
What consequences do increased rainfall, raised temperature and unpredictable weather patterns
(droughts and heavy rains, missing rainy seasons) bring in Tanzania?
Think especially about
1. Urban areas
2. Agriculture (cropping in highlands and lowlands and livestock keeping) and
3. Infrastructure (roads, bridges).
Make lists in the exercise books.
Some ideas for the teacher (this is not an exhaustive list):
1. Urban areas:
 Flooding is especially dangerous in urban areas if drainage is not efficient
and surface is sealed by tarmac
 Extreme heat in urban areas can even kill old people
 Water shortages
 Coastal towns are in danger of extreme weather conditions like tsunamis
 Raising sea level threatens coastal towns
 Landslides can be dangerous if close to mountains (heavy rains cause
them)
2. Agriculture:
 Crops are not adapted to changing climate
 As climate becomes more unpredictable farmers find it harder to manage
their crops (esp when to plant)
 Unpredictable and more extreme climate can lead to losing an entire crop
to drought or to flooding (and one never knows which)
 Water shortage in the countryside during droughts
 Drying rivers or flooding rivers
 Extreme climate conditions can break terraces, irrigation furrows and
other farm structures
 Landslides are dangerous for life and destroy villages and fields
3. Infrastructure:
 Extreme climate conditions such as flooding break infrastructure like
bridges, buildings and roads and it can be very costly to maintain and
repair
 Landslides can break roads and buildings
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