The global average surface temperature is higher than it was in the mid-1800s, and each of the last four decades has been warmer than the previous one. This increase in temperature is called climate change, and it has been caused mostly by human activities such as burning fossil fuels (oil, gas and coal). These activities cause heat-trapping greenhouse gases to be released into the atmosphere, which raises Earth’s atmospheric temperature. Other natural processes can also contribute to climate change, but their effects are being overwhelmed by human activities.
Climate change can harm people in many ways, including making severe weather events more frequent and intense. Flooding, droughts, wildfire and sea level rise all increase as a result of climate change. The number and severity of heat waves are also increasing. The changing climate may cause some plants and animals to move from their natural habitats, and some species will not be able to adapt to these changes and could become extinct. In addition, changes in temperature can influence the distribution of diseases, such as malaria, which is caused by mosquitoes whose ranges are affected by the climate.
It is possible to slow or stop the harmful effects of climate change by reducing emissions of heat-trapping greenhouse gases and by managing land and water resources. Some countries are already taking steps to reduce their greenhouse gas emissions, and many governments and businesses are working to develop technologies that will help limit future warming.