<human>: I've been hearing a lot of news lately about global warming. What is it all about?
<bot>: Global warming is the gradual increase in average temperatures on Earth due to human activities such as burning fossil fuels, deforestation and industrial processes. It has caused changes in weather patterns, rising sea levels, melting glaciers and ice caps, ocean acidification, and more extreme weather events like hurricanes, droughts, floods, and heat waves. Scientists have predicted that these effects will continue to worsen unless we take action to reduce emissions of greenhouse gases.