The “very concerned” number marks an uptick from 2017. In June of that year, just after President Donald Trump announced his plans to pull the United States out of the Paris climate change agreement, only a third said they were very concerned about climate change. The most recent poll was conducted as protesters around the world geared up for marches ahead of the United Nations’ upcoming climate summit .

Two-thirds of Americans say they’re at least somewhat concerned about climate change, a new HuffPost/YouGov poll finds, with 42% describing themselves as “very concerned.”

But the poll also finds a significant generational divide within the GOP: 69% of Republicans under age 45 describe themselves as at least somewhat concerned about climate change, compared to just 38% of those age 45 and older. There’s not a similar difference based on age among Democrats.

Eighty-eight percent of Democrats now say they’re at least somewhat concerned and 65% that they’re very concerned. By contrast, 52% of Republicans say they are at least somewhat concerned, with just a quarter saying they’re very concerned.

Sixty-one percent of Americans say the U.S. should take a global leadership role in trying to prevent climate change, while just 20% say it should not. However, only about a quarter think the U.S. currently is taking such a leadership role, while half say it’s not. Only 23% say the U.S. has done more than most other countries to address climate change, with 35% saying it’s done less, 23% that it’s done as much as other countries, and the remainder that they’re unsure.

Among registered voters, 65% say the issue will be at least somewhat important to their vote in the next presidential election, with 42% saying it’ll be very important. Democrats have an edge on the topic: 48% of voters say they trust the party more to handle climate issues, compared to 34% who trust the Republicans.

Use the widget here to further explore the results of the HuffPost/YouGov survey, using the menu at the top to select survey questions and the buttons at the bottom to filter the data by subgroups.

Here’s a look at some other recent polling on climate change and the environment:

• Most American teenagers “are convinced that humans are changing Earth’s climate and believe that it will cause harm to them personally and to other members of their generation,” according to a new Washington Post-Kaiser Family Foundation poll. Roughly a quarter of 13-to-17-year-olds say they’ve taken action on climate change, either by participating in a walkout or rally, or by writing to a public official. A majority say climate change makes them feel “afraid” and “angry,” but also “motivated.”

• A 57% majority of Americans now call climate change a major threat to the well-being of the country, a Pew Research survey in July found, up from 40% six years ago. Nearly all the change is among Democrats, with Republican opinion largely unchanged.

• Trump “gets some of his worst marks from the American people when it comes to his handling of climate change,” AP-NORC polling in August found. Sixty-four percent disapprove of Trump’s climate change policies. About two-in-three say corporations and the government have a responsibility to combat climate change.

The HuffPost/YouGov poll consisted of 1,000 completed interviews conducted Sept. 17-18 among U.S. adults, using a sample selected from YouGov’s opt-in online panel to match the demographics and other characteristics of the adult U.S. population.

HuffPost has teamed up with YouGov to conduct daily opinion polls. You can learn more about this project and take part in YouGov’s nationally representative opinion polling. More details on the polls’ methodology are available here.

Most surveys report a margin of error that represents some but not all potential survey errors. YouGov’s reports include a model-based margin of error, which rests on a specific set of statistical assumptions about the selected sample rather than the standard methodology for random probability sampling. If these assumptions are wrong, the model-based margin of error may also be inaccurate. Click here for a more detailed explanation of the model-based margin of error.