The record-breaking high temperatures across much of North America appear to be shaping people’s thinking, a survey finds

The warm temperatures that have scorched much of the US appear to be influencing Americans’ acceptance of climate science, with a new poll finding a record level of public confidence that the world is warming due to human activity.

Planet at its hottest in 115,000 years thanks to climate change, experts say Read more

A long-running survey of American attitudes to climate change has found that 73% of people now think there is solid evidence of global warming. A further 60% believe that this warming is due, at least in some part, to human influences.

Both of these findings are record highs in a twice-yearly survey that has been conducted by the University of Michigan and Muhlenberg College since 2008. The latest poll was conducted during May, which was hotter than any May recorded in the contiguous US in 124 years of record keeping, according to the National Ocean and Atmospheric Administration, eclipsing the 1930s during the Dust Bowl era.

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“There’s lots of evidence that contemporary weather is a contributing factor to belief in climate change,” said Chris Borick, director of the Muhlenberg College Institute of Public Opinion. “But there are other factors. People are telling us they are experiencing a climate that isn’t what they remember in the past and the evidence itself, such as declining polar ice, is having an effect. Americans are moving to a lot more confident space on this.”

But there remains a yawning ideological divide when it comes to climate change in the US. The survey found that while 90% of Democrats accept there is solid evidence of climate change, only 50% of Republicans feel the same.

However, Borick said that messaging from those who deny or obfuscate climate science has shifted away from outright rejection of temperature data. While Donald Trump has previously called climate change “bullshit” and a Chinese-inspired hoax, he has rarely spoken of the issue while president apart from framing action to address it as economically costly.

“The talking points have turned more to the cost to mitigate climate change rather than deny its existence,” Borick said. “That said, if you want one factor that influences your view on climate change, it’s party affiliation. Age, race and gender don’t even come close.”

The hot temperatures have persisted in much of the country since the May survey, with Los Angeles hitting a monthly overnight record of 79F (26.1C) on 7 July. Chino, near Los Angeles, saw a record temperature of 120F (48.9C), while Death Valley in California reached 125.6F (52C) on 8 July.

About 80 million Americans have been placed under heat warnings in recent weeks, with cities such as Denver, Colorado and Cheyenne, Wyoming, both experiencing record temperatures.

The heat has been fierce on the US east coast and Canada, too. About 70 deaths have been blamed upon a punishing heatwave experienced in and around Montreal, with further deaths recorded in New York and Pennsylvania due to the high temperatures.

Facebook Twitter Pinterest Children play in a water fountain in Battery Park, in New York, on 2 July as the temperature reached 35C. Photograph: Alba Vigaray/EPA

A string of warm days in New York City helped trigger a return to smog-like conditions on 2 July, when the temperature in the city reached 95F (35C).

Researchers who flew a light aircraft taking measurements over a hazy New York were astonished to find that the ozone concentration was 150 parts per billion. This far exceeds the Environmental Protection Agency’s eight-hour average ozone health standard of 70 parts per billion. The high ozone readings have continued, with preliminary data for Tuesday showing 85 parts per billion in New York.

Ground-level ozone is created when pollutants react to intense sunlight, potentially causing haze or smog. This can cause serious health problems and even death for people who are elderly, sick or who have respiratory conditions.

“This is a disturbingly high level, we were very surprised at the results,” said Russell Dickerson, a professor at the University of Maryland’s department of atmospheric and oceanic science. “The sky was very gray. It reminded me of Beijing. It was like what New York used to be like, before it cleaned itself up.”

Overall air quality in the US has improved markedly in recent decades following the introduction of federal clean air rules. Ozone levels have remained stubbornly high in New York, however.

“We are trying to work out why this is but the recent high level could well be because of the hot, stagnant weather, with weak winds,” Dickerson said. “It’s a public health concern. I’d certainly advise people to stay indoors during the hottest part of the day.”