Scientists might have a PR problem in the United States.

In the eyes of the American public, scientists are seen as respectable and competent — but not necessarily trustworthy, according to a new study.

If scientists want to soften their image, they might try to seem a little more friendly and warm, the researchers said. [6 Politicians Who Got the Science Wrong]

More than 100 adult volunteers were asked in an online survey to rate 42 professions by their perceived warmth (a mixture of friendliness, trustworthiness and good intentions) and competence.

The results showed that stereotypes were pervasive. Teachers, nurses and doctors were seen as both warm and competent. On the other end of the spectrum, prostitutes, garbage collectors and dishwashers were seen as neither warm nor competent. Some jobs, such as writers, police officers and bus drivers, fell in relatively neutral territory. But scientists engendered mixed feelings: They were lumped into the high-competence, low-warmth corner with lawyers, CEOs, engineers, accountants and researchers.

For the second part of their study, Susan Fiske, a professor of psychology and public affairs at Princeton University, and Cydney Dupree,a graduate student in Fiske's lab, focused on the perception of climate scientists — a group for whom credibility and trustworthiness could be all-important for influencing public policy.

Fiske and Dupree asked a new group of 52 online participants to rate, on a five-point scale (1 being the lowest), how much they agreed with each of the following explanations for why climate scientists argue that human activity is largely responsible for climate change worldwide:

Climate scientists wish to: lie with statistics; educate the public; make a simple story into something quite complicated; save the Earth; save humanity; show the public how intelligent and superior to others they are; gain more money from the government for their research; pursue a liberal agenda; save the environment; be provocative; and hurt big corporations.

Climate scientists averaged a fairly good rating of 4.35 across three of the positive motives: to educate the public, save humanity and save the environment. On the distrustful items, climate scientists earned an average rating of 2.16, which is lower than the midpoint (2.5) but still not "cause for celebration," the researchers wrote. Responses varied, and some participants were clearly more distrustful than others. Fiske and Dupree found that the biggest risk factor for public distrust of scientists was the perception that the main motivation of these researchers is gaining grant funding. (This item had a an average ranking of 3.58.)

Overall, the results suggest climate scientists seem to be less distrusted than scientists in the generic sense. (But the researchers noted that the sample of participants in the second poll was slightly more educated and slightly more liberal than the U.S. population in general.) And any distrust of climate scientists might actually stem from factors other than a lack of knowledge.

"People are not idiots," Fiske said in a statement. "The public's issue with science is not necessarily ignorance."

Previous studies have shown that people increasingly know more about the causes behind climate change, so communicating climate science starts with some advantages, the researchers argued.

"Climate science communicators have effectively conveyed much evidence, which should encourage their continuing to educate and communicate," Fiske said. "Just like other communication, science communication needs to continue to convey warmth and trustworthiness, along with competence and expertise."

What might conveying warmth entail? The researchers say climate scientists might want to highlight their good intentions of educating the public, saving humanity and protecting the environment. Climatologists might want to back off arguments strongly intended to persuade; otherwise they risk being perceived as agenda-driven. The researchers wrote that communicating uncertainty is actually "essential to building credibility" in public opinion.

The findings were published last week in the journal Proceedings of the National Academy of Sciences.

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