the third presidential debate , scheduled for wednesday, might seem like a rerun. chris wallace, the moderator and an anchor for fox news, has chosen topics familiar from previous debates, including debt, immigration, foreign affairs, the economy and the supreme court. notably missing is any mention of climate change, which was also almost ignored in the earlier debates. the fate of the planet has come up only in a single question asked by a member of the audience at the second debate, ken bone , who received more attention for his red sweater than for the fact that he works for a coal-fired power plant . michael d. mccurry, a chairman of the commission on presidential debates, said that the moderator and the candidates, not the commission, set the content. irena briganti, a spokeswoman for fox news, referred questions back to the commission. neither of the presidential campaigns responded to requests for comment. this lack of attention might lead some observers to conclude that americans are unconcerned about climate change, but some surveys tell another story. most americans say they are interested in climate change, but they just do not hear much about it. in some ways, this presidential election cycle has brought climate change closer to the forefront than any previous election, and the two campaigns could not provide a more stark contrast. hillary clinton has a published on her website a detailed plan for dealing with climate and energy issues, and the topic was given prominence at the democratic national convention, which included a short film by the director james cameron. last week, former vice president and climate crusader al gore joined mrs. clinton for a rally in miami, where they spoke of a warming planet and its possible effect on storms like hurricane matthew, which had just scraped the florida coast on its way to cause devastating flooding in north carolina . <u+201c>i can<u+2019>t wait to have al gore advising me when i am the president,<u+201d> she told the cheering crowd. but some of her positions, particularly her acceptance of natural gas as a <u+201c>bridge<u+201d> fuel from coal-burning power plants to renewable energy, are troubling to some in the environmental movement. many ardent environmentalists argue that all fossil fuel extraction and use must end, a contingent that would love to ban fracking , and whose philosophy is expressed in the twitter hashtag #keepitintheground. donald j. trump, going further than any previous presidential nominee, ha s said that climate change is a hoax , and has pledged to undo the obama administration<u+2019>s climate initiatives , including the paris climate agreement and the administration<u+2019>s clean power plan, which would require power plants to clean up their emissions. mr. trump has also vowed to expand fossil-fuel exploration . yet the topic still seems oddly distant, and not just because scandal and calumny have overshadowed so many other issues. despite the passion of activists and the issue<u+2019>s undeniable importance <u+2014> president obama has said that <u+201c>no challenge poses a greater threat to future generations than climate change<u+201d> <u+2014> no broad public fervor for the topic has emerged. according to a survey from the yale program on climate communication , 61 percent of americans say that climate change is at least somewhat important to them personally. yet the yale study also found that more than half of those who say they are interested in global warming or think it<u+2019>s important <u+201c>rarely<u+201d> or <u+201c>never<u+201d> talk about the issue with family and friends. in a different study , the yale group found that just a third of americans called protecting the environment and developing clean energy very or extremely important in their vote. among registered voters, party affiliation seems to determine how much they care about climate change . according to a report from the pew research center , 56 percent of registered voters who support mrs. clinton say they care about climate change a great deal. among those who support mr. trump, only 15 percent say the same. anthony leiserowitz, a research scientist at the yale school of forestry and environmental studies and the director of the climate change communication program there, referred to the lack of attention to the issue as an example of <u+201c> the spiral of silence ,<u+201d> a term borrowed from elisabeth noelle-neuman, a german political scientist. <u+201c>when nobody talks about the issue, the clear signal is that this isn<u+2019>t very important,<u+201d> dr. leiserowitz said. <u+201c>ultimately, it comes down to one of the most precious resources on the planet, human attention.<u+201d> he also said that when public figures such as president obama, pope francis and leonardo dicaprio talked about climate change, it could influence how much the public says they care about climate change, how often they search on google about the topic or post on social media. mr. obama<u+2019>s focus on the issue, dr. leiserowitz said, is <u+201c>part of the reason why global warming is no. 6 on the priority list among liberal democrats and it wasn<u+2019>t there before.<u+201d> this problem may be illustrated through the online activities of the clinton campaign, which has published 654 posts on facebook since aug. 1. just five of those posts focused on climate change, and those have not generated a great deal of user engagement. according to an analysis by the new york times, only one of the 100 posts that were most liked, shared and commented on mentions climate change: it offered a link to video of the appearance with mr. gore. jeff nesbit, who worked in the white house in 1991-92 under president george bush and now works with the climate communications organization climate nexus , said that debate moderators might be reluctant to bring up climate change. he explained that could be partly because the candidates<u+2019> positions are already so well known, but also because so many americans have already come to understand that climate change is real, and so <u+201c>it sounds as if they are siding with democrats simply by asking the question, because there<u+2019>s such an imbalance in the political world on the question.<u+201d> sam adams, the director of the united states climate initiative for the world resources institute, noted that while climate change was a strong part of mrs. clinton<u+2019>s platform, it still posed a political danger. the liberal wing of her party finds her too incremental in her attitude toward ending fossil fuel dependence, and more conservative democrats argue that a too-rapid shift to renewables will hurt coal and oil workers. <u+201c>it<u+2019>s not a risk-free issue for clinton to campaign on, either from the left flank or the right flank,<u+201d> he said. and sometimes, the question simply falls through the cracks. lester holt, the nbc anchor who moderated the first debate, did plan to ask about climate change, according to mark kornblau, a senior vice president for communications for nbc news and msnbc. he dropped it, mr. kornblau said, because <u+201c>the early part of the debate ran longer than we had hoped, because there were more interruptions and soliloquies than we expected.<u+201d> correction: october 19, 2016 an article on tuesday about the lack of discussion of climate change during presidential debates misstated part of the name of a school at yale university. it is the yale school of forestry and environmental studies (not sciences). julia simon contributed reporting. like the science times page on facebook. | sign up for the science times newsletter. a version of this article appears in print on october 18, 2016, on page d5 of the new york edition with the headline: little debating a climate divide. order reprints | today's paper | subscribe
for clinton and trump, there<u+2019>s little debating a climate change divide
john schwartz tatiana schlossberg