ESS Standard Topic 6.2

Climate Change

Climate

The atmospheric conditions expected in a particular area over a long period of time. The two main factors are:

• Average temperature with it’s seasonal variations

• The average amount and distribution of precipitation

Weather

The specific conditions being experienced at a particular time or over a short period, can change rapidly and includes:

• Temperature

• Humidity

• Air pressure

• Wind Speed

Climate Graphs

Shows the temperature and precipitation patterns month to month for a defined area.

Climate change

The long-term, sustained changes in the average global weather conditions. Encompassing global warming but broader in range.

Anthropogenic

Human activity - have caused concentrations of atmospheric carbon dioxide to rise significantly with the main acceleration in the last 50 years with the spread of industrialisation and human population increase

Tree Rings

Can give up to 2,000 years of clues for ancient climates. Large rings (warm and wet) Small rings (cold and dry)

Deposited Sediments

Ancient ocean floor sediments, deposited during the last ice age, reveal information about past ocean oxygen levels and their relationship with atmospheric carbon dioxide. 

Old Data / Inferences

Can give up to 2,000 years indicating growth and patterns. E.g. Paintings, Diary entries, Frost Fairs, Sakura blooming periods.

Ice Cores

Form layers of snow and ice layers over up to 800,000 years of insight into historical temperatures, solar intensity, ocean conditions and volcanic eruptions through the dust, pollen, ash and gas bubbles within them.

The Local Ecological Impacts of Climate Change

Biome shifts, species adaptation/evolution, changes to productivity and biodiversity, reduced ecosystem resilience, and ecosystem tipping points

How does Climate impact ecosystems?

Ecologically it affects the resilience of ecosystems and leads to biome shifts.

Biome Shifts Local

• As temperature and precipitation change, biomes may shift to a higher altitude or latitude as the organisms of an ecosystem seek the temperatures they are adapted to.

• Results in invasive species entering ecosystems, which can harm native plants and animals already under stress from the changing climate.

Species Adaption/Evolution Local

• Changes in temperature and precipitation force species to adapt or relocate. 

• Behavioural changes, like altering migration or pollination times, and physical changes, such as growing thinner fur. 

• Species unable to adapt quickly face extinction.

Productivity and Biodiversity Local

• Traditionally colder regions see growth in productivity while other areas may experience losses in productivity and biodiversity

• Rapid climate changes can outpace the ability of species to adapt, leading to declines in ecosystem resilience.

Reduced Ecosystem Resilience Local

• Ecosystems accustomed to stable conditions lose resilience if disturbances become too frequent or severe. 

• Ecosystems with low natural resilience, e.g the tundra, are especially vulnerable.

Examples of Reduced Ecosystem Resilience leading to tipping points. Local

• Desertification in the Sahel: Increased temperatures and decreased rainfall turn fertile land into desert.

• Amazon Rainforest to Savannah: Deforestation and climate change may transform the rainforest into a Savannah.

• Coral Bleaching: Warmer ocean temperatures cause corals to lose their algae and die, disrupting marine ecosystems, as seen in the Great Barrier Reef.

Changes in Ocean Circulation Global

The Atlantic Meridional Overturning Circulation (AMOC) may slow down, impacting global ecosystems. As warming temperatures affect ocean currents, which regulate global climate.

Sea Level Rise Global

• Melting polar ice caps and glaciers, along with thermal expansion of oceans, raise sea levels. 

• This impacts coastal ecosystems, increasing soil salinity and threatening marine biodiversity.

• This salinity increase harms plant species not adapted to high salt concentrations. 

• Mangroves, while salt-tolerant, can only withstand certain levels of salinity. 

• Excessive salt can stunt their growth and reduce their reproductive success.

Monsoon Rains Global

Climate change can intensify monsoon rains, causing severe flooding in some regions while causing droughts in others due to shifts in monsoon patterns.

Tropical Cyclones Global

Warmer ocean temperatures fuel stronger cyclones with higher winds and more rainfall, damaging coastal ecosystems. 

Impacts on Health

• Rising temperatures lead to more frequent, intense heat waves, causing health issues like heatstroke and dehydration. 

• Warmer climates also increase the spread of diseases such as malaria and dengue fever.

Impact on Food Security

• Unpredictable weather (including droughts and floods) damages crops and reduces food production. 

• This results in higher food prices and shortages, particularly affecting poorer regions

Water Scarcity

• Changes in rainfall and melting glaciers reduce freshwater availability, impacting drinking supplies, agriculture, and industries. 

• This water scarcity disproportionately affects the poor and women, raising environmental justice concerns

Economic Impact

• Natural disasters like hurricanes and wildfires, intensified by climate change, destroy property and disrupt businesses, causing financial losses. 

• Industries dependent on weather, such as agriculture and tourism, are also negatively impacted

Example of Economic Impacts

Acapulco Mexico: suffered a devastating hurricane in 2023, intensified by climate change, causing significant damage and exemplifying the greater consequences for low-income countries.

Displacement and Migration

• Severe weather and rising sea levels can force people to leave their homes.

• Coastal and island areas will become uninhabitable due to seawater intrusion on freshwater supplies, leading to large numbers of climate refugees and potential regional conflict.

Environmental Migration

The movement of people to another state or location as the result of the environmental conditions of their previous settlement being too severe.

Ice-albedo Positive Feedback

1. Ice has a high degree of albedo (reflectivity)

2. Larger ice caps on the Earth reflect more of the Sun’s energy back out. 

3. Reducing these caps and ice levels on Earth leads to more absorption of the Sun’s energy resulting in a warmer planet.

Permafrost thawing Positive Feedback

1. Rising temperatures thaw permafrost (less permafrost), releasing more methane and carbon dioxide. 

2. These gases increase the greenhouse effect, causing further warming that accelerates permafrost thaw.

Increased Cloud cover Negative Feedback

1. Rising temperatures increase evaporation from bodies of water

2. Creates more clouds

3. Increases albedo (more reflected light) 

4. Decreases amount of radiation absorbed which decreases temperature  

Forest Fires Positive Feedback

1. Forests absorb and store carbon dioxide. 

2. Increased temperatures and droughts lead to more frequent and intense forest fires. 

3. Burning trees release stored carbon dioxide, enhancing the greenhouse effect, causing further warming that increases the risk of forest fires.

More Plant growth Negative Feedback

1. Higher levels of CO₂ increases plant growth 

2. Therefore more CO₂ is absorbed 

3. Slows down climate change 

Use of the Planetary boundaries Model

The model was made to quantify the limits of the Earths nine major regulating systems and determining the safe operating space of human economic activity to prevent reaching tipping points.