Evidence of Climate Change

CO 2 levels historically rose and fell below 300 ppm. Increase since Industrial Revolution: now reached 400 ppm.

The pattern of global temperature follows the pattern of CO 2 levels

Global temperature rise 1.4 degrees F rise since all 10 of the warmest years occurred in the past 12 years.

Warming oceans Top 2,300 feet of ocean warmed degrees F since Warmer water absorbs more sunlight—warms even more Warmer water expands—sea levels rise

Flowing meltwater from the Greenland ice sheet Shrinking ice sheets The Greenland and Antarctic ice sheets have decreased in mass.

Republic of Maldives: Vulnerable to sea level rise Sea level rise Global sea level rose 6.7 inches in the last 100 years. Predict sea level to rise about 3 feet by the end of this century.

Declining Arctic sea ice Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades.

Glacial retreat Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska and Africa.

Extreme events The number of record high temperature events increasing increasing numbers of intense rainfall events. Formerly “once in a century” storms becoming more common

Ocean acidification More CO2 = more acidity Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30%

Is climate change real? With this evidence plus changes happening in plant and animal life 97% of scientists believe climate change is real AND that it is caused by humans