Climate Change and Global Warming: Causes, Impacts and Mitigation

Meaning: climate change vs global warming

• Global warming refers to the long-term increase in Earth’s average temperature mainly due to greenhouse gas emissions.
• Climate change is a broader term. It includes global warming and other long-term changes such as rainfall pattern changes, extreme weather events and sea-level rise.

Exam line: Global warming is one major cause/component of climate change.

Greenhouse effect and greenhouse gases

The greenhouse effect is the warming of Earth’s surface because certain gases trap heat in the atmosphere.

Main greenhouse gases:

• carbon dioxide (CO2)
• methane (CH4)
• nitrous oxide (N2O)
• water vapour (H2O)
• ozone (O3)
• industrial gases (CFCs/HFCs)

Natural greenhouse effect makes Earth habitable, but enhanced greenhouse effect due to human emissions causes global warming.

Causes of climate change (human and natural)

Human causes (major)

• burning fossil fuels in transport, power plants and industries
• deforestation (reduces carbon absorption)
• agriculture and livestock (methane)
• use of fertilisers (nitrous oxide)
• industrial processes and refrigerants

Natural causes (minor/long-term)

• volcanic eruptions (aerosols)
• solar radiation variation
• long-term earth orbital changes

Impacts on environment, economy and health

Environmental impacts:

• melting glaciers and polar ice
• sea-level rise and coastal flooding
• biodiversity loss and ecosystem disturbance
• more frequent extreme events (heatwaves, droughts, heavy rainfall)

Economic impacts:

• crop loss and food insecurity
• damage to infrastructure due to floods/storms
• increased energy demand (cooling)

Health impacts:

• heat stress and heat stroke
• spread of vector-borne diseases
• respiratory problems due to increased pollution and smoke

Evidence/indicators (temperature, ice melt, sea level)

• rising global average temperature
• retreating glaciers and reduced snow cover
• rising sea levels
• changes in rainfall patterns
• increasing frequency of extreme weather

Mitigation measures (reduce emissions)

Mitigation focuses on reducing greenhouse gas emissions and increasing carbon sinks.

Measures:

• switch to renewable energy (solar, wind)
• energy efficiency in homes and industries
• public transport, EVs and fuel standards
• afforestation and preventing deforestation
• waste management and methane capture
• cleaner production and low-carbon technologies

Adaptation measures (reduce vulnerability)

Adaptation means adjusting to climate impacts.

Examples:

• drought-resistant crops and improved irrigation
• flood control measures and early warning systems
• water conservation and rainwater harvesting
• climate-resilient infrastructure
• heat action plans in cities

International initiatives (basic): UNFCCC, Paris Agreement

• UNFCCC: global framework for climate action.
• Paris Agreement: aims to limit temperature rise by reducing emissions and supporting clean development.

Countries submit plans and work together for mitigation and adaptation.

Role of individuals and communities

• save electricity and use energy-efficient appliances
• use public transport/carpool
• reduce waste and practise 3Rs
• plant and protect trees
• support clean energy and awareness campaigns

Small actions multiplied by many people create large impact.

Key terms explained

• Greenhouse effect — heat trapping by gases.
• Carbon footprint — total greenhouse gas emissions from activities.
• Mitigation — reducing emissions.
• Adaptation — adjusting to impacts.
• Carbon sink — forests/oceans absorbing CO2.

Quick recap (1-minute revision)

• Global warming = rising temperature; climate change = wider long-term changes.
• Greenhouse gases trap heat; human activities enhance greenhouse effect.
• Impacts: ice melt, sea rise, extreme events, crop/health problems.
• Solutions: mitigation (cut emissions) + adaptation (reduce risk).