There are well-understood physical mechanisms by which changes in the amounts of greenhouse gases cause climate changes. The US National Academy of Sciences and The Royal Society produced a booklet, Climate Change: Evidence and Causes (download here), intended to be a brief, readable reference document for decision makers, policy makers, educators, and other individuals seeking authoritative information on the some of the questions that continue to be asked. The booklet discusses the evidence that the concentrations of greenhouse gases in the atmosphere have increased and are still increasing rapidly, that climate change is occurring, and that most of the recent change is almost certainly due to emissions of greenhouse gases caused by human activities.
Further climate change is inevitable; if emissions of greenhouse gases continue unabated, future changes will substantially exceed those that have occurred so far. There remains a range of estimates of the magnitude and regional expression of future change, but increases in the extremes of climate that can adversely affect natural ecosystems and human activities and infrastructure are expected.
View the Climate Change in 60 seconds video:
Click below to browse the interactive booklet: