What are the consequences of climate change? (WJEC Eduqas GCSE Geography B): Revision Note

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The notes on this page cover part 2.4.3 of the WJEC Eduqas GCSE B Geography.

2.4.3 What are the consequences of climate change?

The consequences of climate change for people and environments.

Coverage must include the consequences on at least two of the following:

• Farming and food supply

• Wildlife and habitats

• Water and water supplies

• Where people live and population movement

• Tourism and tourist destinations

Consequences of climate change on farming and food supply

• Wheat and maize yields have been negatively impacted in many regions since 1960

• Crop yields are estimated to continue reducing by over 20% as temperatures increase

• The effects are that rice and soybean yields have been smaller in all major production regions 

• The largest impact has been on the price and production of food for daily consumption

  • Production has decreased

  • Prices have increased

• A changing pattern of rainfall will also threaten crop production

  • Too little rain and crops will fail

  • Too much rain and crops will rot in the fields

• Suitable areas for agriculture will change

  • Farmers may have to change their crops 

  • Areas that could grow certain crops will have to change

    • Wheat grown in the USA will have to be grown in Canada

    • This would negatively affect the USA's economy while boosting Canada's

• Reduced availability of water will mean that irrigation is limited or impossible

• Food shortages will lead to malnutrition and famine

Consequences of climate change on wildlife and habitats

• Animals and habitats are adapted to the climate in which they live

• Any changes in the climate will impact on the wildlife and the habitats in those areas

Impact of climate change on biodiversity

• Climate change can lead to habitat loss, changes in the food web and extreme weather events

• All of these can reduce biodiversity

  • For example, coral bleaching due to increased sea temperatures reduces the variety of species in coral reefs

  • This can reduce the ability of coral reefs to cope with other changes, like ocean acidification or increased tropical storms

Impact of climate change on habitat fragmentation

• Rising temperatures and changing precipitation patterns can shift habitats, leading to fragmented landscapes

• Climate change can fragment habitats in various ways:

  • Increased desertification: expanding deserts can divide ecosystems, making it harder for species to find resources and migrate

  • Increased rates of forest fires: more frequent and intense fires can break up forest ecosystems, isolating populations and reducing biodiversity

  • Melting polar ice caps: loss of ice habitats can fragment the habitats of polar species like polar bears and penguins, affecting their ability to hunt and reproduce

  • Species in mountainous regions might be forced to move to higher altitudes, creating isolated populations

• These changes reduce the resilience of ecosystems by isolating species and limiting their ability to adapt to new conditions

Changes in biomes

Movements of biomes

• Biomes, such as forests, grasslands and tundra, may shift towards the poles or higher altitudes as species (including plants) shift ranges to find suitable climates

  • For example, in North America, temperate forests are moving northward, slowly replacing boreal forests

  • As species move to new areas or experience changes in their habitats, they may face new competition, predation, or disease

Transformation of existing biomes

• Current biomes may change in structure and composition

  • For example, the Arctic tundra is transforming into shrubland as warmer temperatures allow shrubs to grow

• Seasonal cycles are changing, e.g.

  • Plant species are producing flowers earlier in the year

  • Animals are producing young earlier in the year

  • Bird migratory patterns may lose their synchronisation with their habitats, leading to a change in migration patterns

• Polar ice and glaciers are retreating; it is thought that there may soon be no summer ice in the arctic if rates of warming there continue

  • The loss of glacier ice from mountain ranges may affect the water supplies of many people and surrounding wildlife

Loss of unique biomes

• Some biomes may disappear if conditions become unsuitable for the species that inhabit them

  • For example, alpine regions may lose their unique flora and fauna as temperatures rise and snow cover decreases

  • This can lead to declines in population numbers and even extinction in some cases

Consequences of climate change on water and water supplies

• Climate change can lead to alterations in precipitation patterns

  • This results in changes in water availability

• Some regions may experience increased rainfall and flooding

• Others may face more frequent and severe droughts

  • These both impact water resources for agriculture, drinking water, and ecosystems

  • There will be reduced availability and quality of freshwater resources due to the changes in precipitation patterns and increased evaporation

Water stress

• Water stress occurs when available water resources are not sufficient to meet the demand

• The number of people suffering water stress is increasing

  • Approximately 4 billion people around the world suffer water stress for at least one month a year

• The UN Predicts that 5 billion people could face water shortages by 2050

Impact of climate change on where people live

• Almost 32 million people were displaced by weather-related hazards in 2022

  • Over 200 million people may be forced to move by 2050

• The causes of the displacement include:

  • Rising sea levels

  • Drought

  • Food and water shortages

  • Increased health risks

Rising sea levels

• Sea levels have been rising faster in recent years

• Increased storm frequency and severity

• These will both lead to increased flooding

  • Increased flooding lead to displacement of large numbers of people

• The migration of people from the south of Bangladesh

  • People are relocating to urban areas due to coastal erosion and flooding caused by sea level rise

Drought

• Less frequent precipitation and increased evaporation lead to drought

• As areas become drier, they become more vulnerable to drought

• In parts of East Africa between 2020 and 2022 there were five failed rainy seasons

  • This displaced over 1.2 million people in Somalia

• From 2011 to 2017, California experienced extreme drought conditions

• By January 2014, the entire state was in a drought emergency, with Central Valley being the worst-affected area

• With continued lower than normal precipitation and overdependence on the Colorado River, water supplies dropped

Food and water shortages

• Food shortages and price spikes following extreme weather events, such as hurricanes or droughts

  • Water rationing in Cape Town, South Africa, during a prolonged drought leading to severe water shortages (2017-2018)

  • Decline in wheat yields in Australia due to heat stress and reduced rainfall

  • Outbreak of coffee leaf rust in Central America resulting in significant losses for coffee farmers

Increased health risks

• Increased temperatures and lack of precipitation may lead to the spread of diseases:

  • Italy has experienced cases of malaria since 2017, when it was previously a malaria-free area

  • An additional 280 million people may be affected by malaria

  • Waterborne diseases are more likely to spread

• Heat waves may become more frequent

• Heatstroke, dehydration and sunburn increase during heat waves

  • Heatwaves in Europe (2003) resulted in thousands of deaths, particularly among vulnerable populations such as the elderly

• Stagnant air during heat waves increases air pollution levels:

  • Respiratory diseases increase and those suffering from respiratory illnesses such as asthma may be more affected 

• Increased temperatures negatively affect people with cardiopulmonary diseases

• Diets may be restricted by food shortages leading to malnutrition and famine

Impact of climate change on tourism

• Places which are popular with tourists are often reliant on their climate as part of the attraction

• The tourist industry in these areas may be negatively affected by an increase in:

  • Tropical storm frequency and severity

  • Water shortages

  • Melting of snow and ice leading to the closure of ski resorts

• In the Caribbean tourism makes a significant contribution to the economies of many countries

  • Tourism employs over 700,000 people

• Many Caribbean countries' popularity is due to their climate

• Changes to the climate which are already occurring in the Caribbean include:

  • Average temperature has increase by over 1^°C since the 1950s

  • An increase in water temperatures

  • Drought

  • Changes in coral reefs

  • More severe and frequent storms

• The 2017 hurricane season was particularly severe with Hurricane Irma and Marie causing destruction over many islands

  • Over 90% of Dominica's buildings were destroyed

• In 2020, there were 30 named storms, many of which caused devastation to people living in the Caribbean

  • These all impacted on the tourist industry

  • Many tourist resorts did not reopen; others took many months, even years to rebuild