Global Temperature and Carbon Dioxide (CO2)
Measurements from thermometers and satellites unequivocally show that climate is warming. Each of the last three decades has been much warmer than the one before it, with each one setting a new and significant record for the highest global temperature. Confirmation of global warming also comes from melting glaciers, rising sea levels, arctic sea-ice retreat, reduced snow cover, and other changes. Long records of past climate show that the warming of the past 50 years is clearly unusual in a long-term context.