Understanding Climate Change: Causes and Effects

What Is Climate Change?

• Climate change can happen naturally, but human activities like burning fossil fuels are accelerating warming by emitting greenhouse gases such as carbon dioxide and methane, which trap heat and raise global temperatures.Energy, industry, agriculture, and waste disposal are major emitters of greenhouse gases.
• Greenhouse gas concentrations are at their highest levels in 2 million years, continuing to rise.
• The Earth is about 1.1°C warmer than in the 1800s, and the last decade was the warmest on record.
• Temperature rise impacts other areas due to the interconnected nature of the Earth's systems
• Consequences: intense droughts, water scarcity, severe fires, rising sea levels, flooding, melting polar ice, catastrophic storms and declining biodiversity.
• Climate change affects people's health, food production, housing, safety, and work.
• Vulnerable populations, such as those in small island developing States, are already experiencing climate impacts.
• Sea-level rise and saltwater intrusion have displaced entire communities.
• An increase in "climate refugees" is expected.
• Limiting global temperature rise to 1.5°C can help avoid the worst climate impacts and maintain a habitable climate.
• Current carbon dioxide emissions could increase global temperature by as much as 4.4°C by the end of the century.

Taking Action

• Emissions that cause climate change come from every part of the world; some countries produce much more than others.
• The 100 least-emitting countries generate 3% of total emissions.
• The 10 largest emitters contribute 68%.
• Everyone must act on climate change, those who create more of the problem have a greater responsibility.
• Solutions exist to the climate change challenge that can deliver economic benefits, improve lives, and protect the environment.
• Global agreements like the UN Framework Convention on Climate Change and the Paris Agreement help to guide progress.
• Three broad categories of action: cut emissions, adapt to climate impacts, and finance required adjustments.
• Switching energy systems from fossil fuels to renewables like solar can reduce emissions.
• A growing coalition of countries is committing to net zero emissions by 2050.
• ~50% of emissions cuts must be in place by 2030 to keep warming below 1.5°C.
• Fossil fuel production must decline by ~6% per year between 2020 and 2030.
• Adapting to climate consequences protects people, homes, businesses, livelihoods, infrastructure, and natural ecosystems.
• Adaptation is needed everywhere, prioritize for the vulnerable with fewer resources to cope with climate hazards.
• Early warning systems for disasters can save lives and property, and can deliver benefits up to 10 times the initial cost.
• Climate action requires significant financial investments.
• Climate inaction is more expensive.
• Industrialized countries need to fulfil their commitment to provide $100 billion per year to developing countries.

Explore the causes and far-reaching effects of climate change, including greenhouse gas emissions from human activities and the resulting consequences such as droughts, fires, and rising temperatures. Understand the impact of energy, industry and agriculture on climate. Learn what's causing the earth to warm.