Thousands of Nobel laureates, college professors, university presidents, writers and lawmakers are urging the 2016 U.S. presidential candidates to take some time to focus on science during this election cycle. More than 44,000 people have signed an online petition pushing for a presidential debate devoted to climate change, energy, health issues and water technology.

"Science topics are often kind of cast aside, and we want them to be reframed as 'These aren't science challenges, they are human challenges,'" said Sheril Kirshenbaum, who is a researcher at the University of Texas at Austin working to enhance the public's understanding of science and a co-founder of Science Debate, the group behind the push to overhaul what topics candidates discuss during live televised events.

The group first advanced the notion that science should be part of the political conversation during the 2008 presidential campaign. That year, only six of 300 presidential debate questions submitted by journalists were about climate change, the group found. "We were watching the campaigns and the debates leading up to 2008 election, and we were frustrated that science wasn't coming up at all," Kirshenbaum said.

Advocates hope the science-debate movement will gain more traction this year amid a growing national debate on whether climate change is making natural events, such as the wildfires in California, more frequent and dangerous. A discourse on science should reflect a candidate's values, not his or her knowledge of the periodic table of elements, Kirshenbaum said.

"We by no means want this to be a pop quiz," she said. "I think just it's about just getting a sense of what they would prioritize -- everything from funding of some of the science agencies to their plans for space exploration."

To some scientists, a debate focused on science would be pivotal in determining a candidate's leadership abilities and intelligence.

Climate scientist Jonathan Koomey, a research fellow at the Steyer-Taylor Center for Energy Policy and Finance at Stanford University, said he wants politicians to pay more attention to chemistry, climate, genetics and science education. He would be interested in a debate that covers what presidential hopefuls would do to cut carbon emissions. He also wants to know where candidates draw the line with genetic modification and how they would deal with the thousands of chemicals that have never been tested because of their longtime and widespread use by companies. In addition, Koomey cares about interdisciplinary education and wishes more scientists would work with other departments on solutions to problems.

"All of these issues deal with values and are technical, and it is the role of the politicians to explain how their values are not only consistent with science, but also how they will lead to a better society," Koomey said.

But are the odds stacked against a science debate? It doesn't help that science is at the bottom of the list when it comes to topics considered by Americans as they plan to cast their votes, according to a recent Gallup poll. Instead, voters said they are more likely to mull over the economy, foreign affairs, health-care policy, immigration, race relations, terrorism or wealth distribution when they vote.

Some Americans also do not believe that science should be an authoritative voice in policy. A 2015 study conducted by the University of Texas at Austin surveyed 2,000 registered voters to determine how strongly they felt that lawmakers should listen to scientists on 16 topics of policy, with 0 meaning not at all and 10 meaning very strongly. Researchers found that voters across all issues averaged 6.4, which indicated voters generally wanted politicians to take scientific findings into consideration. But the study shows the findings varied when analyzed by party: Democrats averaged 7.46, while Republicans and Independents scored 5.58 and 5.84, respectively.

Presidential-debate committees frequently crowd-source questions from journalists or voters who live near where the debate is held, but candidates have some influence on the subject matter of the questions, said Geoffrey Skelley, the media-relations coordinator at the University of Virginia Center for Politics. He said the complexity of scientific topics also may explain why those issues are often overlooked on the campaign trail.

"Anything with nuance is difficult to talk about on the campaign trail, especially in the 24-hour media world, which runs soundbites," Skelley said. "A candidate can talk about something complicated in front of an audience for an hour and then CNN may only run a 20-second comment that dumbs down what they said."

Critics of the science debate argue that such issues shouldn't be segregated from general topics that matter to voters. "Science plays a role to Iran nuclear weapons negotiations to climate change to health care," said Roger Pielke Jr., a professor at the University of Colorado and director of its Center for Science and Technology Policy Research. "The idea that we can carve off science and have a debate about it is unfair to science and to policy."

Sheila Jasanoff, a professor of science and technology studies at the Harvard Kennedy School in Cambridge, Massachusetts, noted that most debate formats leave little time to address technical issues.

"If there were to be a special debate, I would strongly favor calling it a 'science and society' debate, and not just a science debate," Jasanoff wrote via email. "I would not want to create a situation where candidates can retreat to uttering bland statements about how they value, respect, and revere science ... I would ask their views on funding for the social sciences, pointing out that Congress periodically wants to cut this; but I would insist they explain their position."

But Kirshenbaum says that part of Science Debate's mission is to not tolerate excuses like "I am not a scientist" from candidates who attempt to circumvent scientific issues.

"[Science is complex,] but so is the economy, so is foreign policy," she said. "These are all complex issues, and the candidates are not foreign diplomats, just as they are not scientists."