Ocean acidification: Since the start of the Industrial Revolution, the acidity of the ocean surface has increased about 30%
Sea level rise: Global sea level rose about 17 centimeters (6.7 inches) in the last century. The rate in the last decade, however, is nearly double that of the last century.
Warming oceans: The oceans have absorbed much of this increased heat, with the top 700 meters (about 2,300 feet) of ocean showing warming of 0.302 degrees Fahrenheit since 1969.
Shrinking ice sheets: The Greenland and Antarctic ice sheets have decreased in mass.
Declining Arctic sea ice: Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades.
Extreme events: The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950.