Global warming is one of the most serious environmental problems of our time. Scientists say that the average temperature of the Earth is rising every year. As a result, glaciers are melting, and sea levels are increasing. Some islands may disappear completely, and polar bears may lose their natural home. Global warming is caused by human activity: people burn fossil fuels, cut down forests and produce too much pollution. However, people can change the situation. Modern technologies allow us to use renewable resources such as wind and solar power. Moreover, many countries are developing electric transport to reduce harmful emissions. If more governments support these ideas, future generations will have a chance to live on a healthy planet. Protecting the environment is a responsibility we all share.