The Overheated Earth
Global mean temperatures on land and in the oceans have been slowly increasing over at least the last 50 years. The science confirms that this warming trend is primarily due to the accumulation of greenhouse gases in the Earth’s atmosphere. The principal greenhouse gas is carbon dioxide, but methane and nitrous oxide also contribute to the warming trend. Global warming is changing the Earth’s climate in ways that are causing severe harm to tens of millions of vulnerable people, fragile ecosystems, and global biodiversity. Natural disasters are becoming more frequent and more destructive. Sea levels are rising—threatening coastal cities and vulnerable communities around the world. Millions of people are living in low-elevation coastal zones that will eventually be flooded by the rising oceans and extreme weather. The greater incidence of drought and floods is deepening poverty and driving millions of people from their homelands, seeking refuge in less threatening environments. Climate change is increasingly a factor in intensifying regional conflicts. Climate-driven migration is becoming a global problem. Scientists are increasingly recognising that the changing climate is in fact a climate crisis.