Science: why is there a need to act?
Scientists, researchers, and affected people around the world report changes beyond the natural variation of temperatures on land and in the ocean, as well as abnormal trends in the timing of seasons, in rainfall patterns, and in many other systems. The science on climate change is clear. There is no question that these abnormal changes result from global warming due to an increased greenhouse effect caused by the vast amounts of greenhouse gases added to the atmosphere by human activities.
In response to this, an international climate regime has developed. Governments, intergovernmental organizations, non-governmental organizations, businesses, research bodies, civil society and more are working together to build the science and knowledge that allow us to tackle the causes and threats of climate change.