Scientific evidence is growing that man–made emissions of greenhouse gases are having a noticeable effect on the earth's climate. Globally, seven of the ten warmest years on record were in the 1990s. In the future, the earth's climate could warm by as much as 3oC over the next 100 years. The social, environmental and economic costs associated with this could be huge. Climate change is one of the most serious environmental threats facing the world today. Its impacts will be felt across the world, as sea level rise threatens the existence of some small island states and puts millions of people at risk. Temperature increases, drought and flooding will affect people's health and way of life, and cause the irreversible loss of many species of plants and animals.