Yale Program on Climate Change Communication

3. Perceived Risks of Global Warming

3.1. Six in ten Americans think global warming is affecting weather in the United States.

The impacts of global warming are starting to be felt in the United States. According to the 2014 U.S. National Climate Assessment:http://nca2014.globalchange.gov/highlights/overview/overview

“Residents of some coastal cities see their streets flood more regularly during storms and high tides. Inland cities near large rivers also experience more flooding, especially in the Midwest and Northeast. Insurance rates are rising in some vulnerable locations, and insurance is no longer available in others. Hotter and drier weather and earlier snow melt mean that wildfires in the West start earlier in the spring, last later into the fall, and burn more acreage. In Arctic Alaska, the summer sea ice that once protected the coasts has receded, and autumn storms now cause more erosion, threatening many communities with relocation.”

In line with this assessment, six in ten Americans (59%) think global warming is affecting weather in the United States, with about half thinking weather is either being affected “a lot” (25%) or “some” (27%). Only 5% think global warming is not affecting U.S. weather, while 10% said global warming is not happening. One in four (26%) said they did not know or did not provide a response.

The percentage of Americans who think global warming is affecting the weather “a lot” or “some” has risen slightly since the question was first asked in 2013, from 48% to its current level of 52%.

3.2. About one in three Americans think people in the U.S. are being harmed “right now” by global warming.

Only about one in three Americans (35%) think people in the U.S. are being harmed by global warming “right now.”

3.3. Most Americans think global warming is a relatively distant threat, although more are coming to understand that it will harm people.

Americans are most likely to think that future generations of people (71%), plant and animal species (71%), and the Earth (70%) will be harmed a “great deal” or a “moderate amount” by global warming. A majority also think people in developing countries (62%), the world’s poor (62%), people in the U.S. (58%), and their own grandchildren (56%) or children (50%) will be harmed.

They are less likely to think that those closest to them – people in their community (48%), their family (47%), themselves (43%), and members of their extended family living outside the U.S. (41%) will be harmed.

Although Americans perceive global warming as a relatively distant threat, since our March 2015 survey, the number of Americans who think climate change will cause harm to humans has increased substantially. More Americans now think global warming will harm: People in developing countries (+9 percentage points since March 2015; see Data Tables), people in the U.S. (+9 points), the world’s poor (+9 points), future generations (+7 points), their own family (+5 points), them personally (+6 points).

3.4. Four in ten Americans say they have personally experienced the effects of global warming, two in three say they have not.

Four in ten Americans (40%) say they have personally experienced the effects of global warming. Six in ten (60%) 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 the surveys began in 2008.

3.5. Four in ten Americans think there is at least a 50% chance that global warming will cause humans to become extinct. One in four think there is less than a 10% chance. 

Four in ten Americans (39%) think the odds that global warming will cause humans to become extinct are 50% or higher. That includes 6% who think there is at least a 90% chance global warming will cause human extinction.

However, a majority of Americans (58%) think the odds of human extinction from global warming are less than 50%, with one in four (26%) saying there is less than a 10% chance.