A photo taken on February 12, 2015 in Paris, shows the Eiffel Tower through thick smog. (AFP PHOTO / PATRICK KOVARIK)

Friday, members of the American Thoracic Society visited Congress to share results of a new survey that indicates . Health impacts from the changing climate are expected to increase as well, the doctors surveyed said.

The top concern doctors cited? Climate-related increased air pollution, which is already worsening illnesses in patients. Air pollution is known to cause lung cancer and has been linked to COPD, asthma and other respiratory illnesses, as well as heart attacks and heart disease. Without more stringent pollution control guidelines, the problem could get worse. Hot, humid weather also exacerbates the effect of existing ozone in the air, according to the EPA.

Allergies to mold and pollen as well as weather-related injuries and deaths, such as those from flooding or heat stroke, are the other top concerns among the M.D.s surveyed. The sick, the elderly, and people in poverty are particularly at risk for these and other effects, the group also said, according to post on the ATS's Congressional visit.

(MORE:)

In October, a report found that the majority of Americans — though they accept the science of human-caused climate change — .

The majority of people surveyed either skipped the question asking which health problems are related to climate, or said they didn't know. One in four (27 percent) named at least one health problem related to global warming, and 10 percent answered — wrongly — that there are no health problems associated with it at all, the report stated.

But that's not the case. "Every American, whether they know it or not, has been affected by climate change," Edward Maibach, the director of George Mason University's Center for Climate Change Communication, told weather.com last week.

As climate-caused hardships, such as the California drought, continue, it's likely more people will express greater concern for their health as it relates to climate change, Maibach's report found.

"When people tell us they've personally experienced climate change, more often than not, what they're thinking about is a change in the weather in their part of the country," Dr. Maibach said. Beliefs in climate change are "almost always related to observations that they have made in their own little niche of the world."

MORE ON WEATHER.COM: NASA Photos of Changing Ice

NASA Change: Arapaho Glacier, Colorado (1898)

The Aprapaho Glacier in Colorado in 1898. (NASA)