Climate change is documented by decades of measurements across atmosphere, oceans, ice sheets, and ecosystems. These statistics tell a consistent story of a warming world with accelerating impacts.
Temperature Rise
Global average temperature has risen approximately 1.2°C (2.2°F) since pre-industrial times. The past decade was the warmest on record. Each of the last four decades has been successively warmer than any preceding decade since 1850.
Atmospheric CO2
Atmospheric CO2 concentration has risen from 280 ppm pre-industrial to over 420 ppm today—the highest level in at least 800,000 years. Annual emissions exceed 36 billion tonnes of CO2, with concentrations rising about 2.5 ppm per year.
Ocean Changes
Oceans have absorbed over 90% of excess heat trapped by greenhouse gases. Sea surface temperatures are at record highs. Ocean acidity has increased 30% since pre-industrial times as seawater absorbs CO2.
Ice Loss
Arctic sea ice volume has declined by 75% since 1979. Greenland and Antarctic ice sheets lose over 400 billion tonnes of ice annually. Global glacier mass has decreased every year for over 30 consecutive years.
Extreme Weather
Heat waves are 5 times more likely than in pre-industrial times. Heavy precipitation events have increased by 30% globally. Economic losses from weather disasters exceed $300 billion annually.
Looking Forward
Without dramatic emissions reductions, temperatures could rise 2.5-4°C by 2100. Each tenth of a degree brings additional impacts. The statistics underscore the urgency of climate action.