Yale Program on Climate Change Communication

3. Perceived Risks of Global Warming

3.1. Increasing numbers of Americans say they have personally experienced the effects of global warming.

More than four in ten Americans (44%) say they have personally experienced the effects of global warming, while over half (56%) say they have not.

The number of Americans who say they have personally experienced the effects of global warming is at its highest level since our surveys began in 2008, and has increased by 14 percentage points over the past three years.

3.2. Four in ten Americans think people in the U.S. are being harmed “right now” by global warming.

About four in ten Americans (42%) think people in the U.S. are being harmed by global warming “right now,” the highest level since our surveys began in 2008 and seven percentage points higher than in our May 2017 survey.

3.3. Half of Americans think they or their family will be harmed by global warming, although they think others will be harmed more.

Increasing numbers of Americans understand that global warming will cause harm. They are most likely to think that plant and animal species (75%, +4 percentage points since our last survey in May 2017), future generations of people (75%, +4 points), people in developing countries (71%, +9 points), the world’s poor (71%, +9 points), and people in the U.S. (67%, +9 points) will be harmed a “great deal” or a “moderate amount” by global warming. Half or more also think people in their community (55%, +7 points), their family (54%, +7 points), and they themselves (50%, +7 points since May 2017) will be harmed. These levels of perceived risk are the highest since our survey began in 2008.

3.4. Most Americans think global warming will have future impacts.   The majority of Americans think global warming will have significant impacts over the next 20 years. Six in ten or more think global warming will cause more melting glaciers (67%), severe heat waves (64%), droughts and water shortages (63%), floods (61%), severe air pollution (60%), or intense hurricanes (60%).  At least half think global warming will cause more forest fires (59%), extinction of plant and animal species (59%), famines and food shortages (58%), or abandoning of large coastal cities due to rising sea levels (52%).

When asked which one impact they are most worried about, Americans say droughts and water shortages (12%), melting glaciers (10%), extinctions (9%), intense hurricanes (8%), and famines and food shortages (8%).