What is Climate Change?

Climate change means long-term changes in temperatures and weather patterns. These changes can be natural, for example due to a change in solar activity or volcanic eruptions.  However, since the beginning of the 19th century, human activities have been the main cause of climate change, mainly due to the burning of fossil fuels such as coal, oil and gas.

Burning fossil fuels releases greenhouse gases that act as a blanket surrounding the Earth, trapping the sun's heat and increasing the temperature. The main greenhouse gases contributing to climate change are carbon dioxide and methane. These gases are released, for example, when gasoline is burned in cars or when coal is used to heat buildings. Deforestation and deforestation also release carbon dioxide. Agriculture and oil and gas operations are the main sources of methane emissions. The key sectors contributing to the production of greenhouse gases are energy, industry, transport, construction, agriculture and land use.

Humans are responsible for global warming

Climatologists have proven that human activities are responsible for most of the global warming over the past 200 years. Activities like those above produce greenhouse gases that are causing the world to warm faster than at any time in the last 2000 years.

The average surface temperature of the Earth is currently 1.2°C warmer than it was in the late 18th century (before the Industrial Revolution) and is warmer than at any time in the last 100,000 years. The last decade (2011–2020) was the warmest on record, and each of the last four decades has been warmer than any previous decade since 1850. Many people think climate change just means warmer temperatures, but rising temperatures are only part of the problem. The earth is a system where everything is interconnected, and changes in one area can affect other areas.

Consequences of climate change

The consequences of climate change include intense droughts, water shortages, severe wildfires, rising sea levels, floods, melting polar ice, catastrophic storms and declining biodiversity.

Effects on people

Climate change affects health, the ability to grow food, housing, safety and employment. Some groups of people are more vulnerable to the effects of climate change, such as residents of small island states and developing countries. These communities already face problems such as rising sea levels and salt water seeping into drinking water, leading to the displacement of entire communities and the risk of famine due to prolonged droughts.

Every increase in global warming matters

UN reports indicate that limiting global warming to a maximum of 1.5°C would help avoid the worst impacts of climate change. However, current policies predict a temperature increase of 3°C by the end of the century. Climate-changing emissions come from all parts of the world, but some countries produce more emissions than others. The largest emitters are China, the United States, India, the European Union, Indonesia, the Russian Federation and Brazil, which together account for approximately half of global greenhouse gas emissions.

Necessary measures

Solutions to climate change can bring economic benefits, improve quality of life and protect the environment. There are global frameworks and agreements such as the Sustainable Development Goals, the United Nations Framework Convention on Climate Change and the Paris Agreement that guide progress. The three main categories of measures include reducing emissions, adapting to climate impacts and financing the necessary adaptations.

Switching from fossil fuels to renewable energy sources such as solar and wind power will reduce climate-changing emissions. Emissions must be halved by 2030 to limit warming below 1.5°C. The use of coal, oil and gas needs to be reduced, while fossil fuel reserves should remain in the ground to avoid catastrophic levels of climate change.

Adapting to the consequences of climate change protects people, households, businesses, livelihoods, infrastructure and natural ecosystems. Adaptation must be a priority for the most vulnerable people with the least resources to cope with climate risks. The return on investment can be high – for example, disaster early warning systems can save lives and property and bring benefits of up to ten times the initial cost.