Urban areas are particularly vulnerable to the impacts of climate change. The density of people and assets within a relatively small geographical area means higher risks. Replacing natural vegetation with artificial surfaces and buildings creates unique microclimates with different temperatures, moisture levels, wind direction and rainfall patterns. There are limited open spaces to absorb runoff, which makes cities especially vulnerable to flooding. Vast expanses of pavement and other artificial surfaces trap heat and make cities hotter during summer, even at night. All this is amplified by the changing climate and linked with other socioeconomic changes. Demographic trends such as urbanisation and increased competition for water are leading to regional water scarcity. An ageing population means that more people are vulnerable to heatwaves. Cities must take steps to ensure they are prepared for the future — not just to avert environmental disasters, but to enhance the quality of life and prosperity of generations to come.
Use the activities below to design a teaching session on adaptation to climate change.
Ask your students to raise their hands if they have seen a disaster movie in which a modern city is wiped out by a tidal wave or other disaster caused by runaway climate change. Explain that, in contrast to the Hollywood version, climate change is typically a slower process, with gradual impacts. Nevertheless, there is clear evidence that the world’s climate is dramatically changing, and that it will have an impact on our lives.
Point out to your students that we are already experiencing changes to the climate that may be bellwethers of the future. Summers are now on average 2ºC warmer, and heavy rainfall events five times more frequent, than 30 years ago. Every year is hotter than the previous, and increasingly severe typhoons and hurricanes are hitting coastal areas around the globe. In the coming decades, we can expect extreme weather events of increased frequency and intensity. In fact, what’s considered extreme weather today — for example heatwaves and thunderstorms — could be routine by 2050. Sea levels are projected to rise by 30 to 40 cm by then.
Explain that preparation is always cheaper and more effective than reaction or recovery. Some risks can be mitigated or avoided at a small cost and with careful planning. A city can’t turn away an approaching hurricane, but an early warning system can save a great many lives by giving people enough time to find shelter. The ability to withstand such shocks is called resilience. Adaptation is the process of identifying climate risks and opportunities, assessing the options for managing them, and implementing the most sustainable measures to moderate the risks and exploit the opportunities. Because the climate will continue to change throughout the century, along with our responses to it, adaptation should be seen as a journey rather than a destination.
Offer some examples of the compound benefits of adaptation. Increasing and interlinking a city’s green spaces, for instance, can help with the absorption of floodwater and rainwater and reduce the urban heat island effect, making the city more resistant to heatwaves and more energy efficient. The increased greenery absorbs noise and air pollution, improves water and energy security, and contributes to the physical and mental health of residents. Green roofs and walls utilise existing infrastructure to improve local microclimates in a similar way. Even a patch of grass counts! Urban communities can green their neighborhoods in many small ways — by kerbside tree planting, park renovation, the construction of courtyard gardens, or supporting urban wildlife (e.g. putting up birdhouses or bat boxes).
Ask your students to write an essay about what their city might look like in 2050, and the kind of threats they envision. Ask them to read the case study on Barcelona’s water shortage for inspiration.
Before they start writing, draw up a list together with your students of the climate change–induced vulnerabilities and threats that may affect them. Prepare in advance some examples of environmental problems over the last five years. Ask students to mark on a city map any areas that are at risk or that are particularly vulnerable to climate change.
Water war in Barcelona
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Start the discussion by listing some of the impacts of climate change: tidal flooding (due to the rise in sea level), fluvial flooding (rivers and streams), surface water flooding (from heavy rainfall and the overburdening of storm drains), extreme snowfall, long and frequent heatwaves or excessively high temperatures, extreme weather events (e.g. windstorms), food or water shortages due to drought, excessive air pollution, disease outbreaks (including food-borne diseases and diseases carried by animals or insects, or by pests that have appeared only recently due to a change in the local climate), and ambient noise.
Discuss how climate change has had, or will have, an impact on your own city. What can be done to mitigate or prevent these risks?
Share some examples of what a city can do to reduce the severity of heatwaves and the urban heat island effect:
Share some examples of what cities can do to reduce the severity of drought:
Discuss what your school can do to adapt to climate change. Share the following ideas, based on what other schools have done:
Share the case study on rain gardens with your students and discuss with them the possibilities for an urban garden or a green space project in your school.
Encourage students to volunteer for disaster relief organisations in times of need and organise first aid training.
Rain gardens in London
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