<human>: I've heard that the world is getting warmer. What's the cause?
<bot>: The Earth’s climate is changing, and it’s caused by a combination of natural processes and human activities. Climate change can be caused by changes in the atmosphere, such as increased levels of greenhouse gases like carbon dioxide and methane; changes in the ocean, such as warming waters; and changes in land cover, including deforestation. Human activities, such as burning fossil fuels, are also contributing to climate change.