Dr. Epstein, who served as the associate director of Harvard Medical School’s Center for Health and the Global Environment, produced a series of seminal papers examining the public health implications of climate change and its impacts.
Rather than confine his work to academic circles, he devoted much of his career to speaking publicly about humans’ need to curb greenhouse gas emissions or risk facing disastrous consequences. Dr. Epstein was an adviser to former vice president Al Gore for the 2006 Oscar-winning documentary film “An Inconvenient Truth.”
In an e-mail, Gore said that Dr. Epstein “always found the time to make sure that the latest research was relayed to the public.”
“His rare ability to communicate the subtleties and complexities of his field in layman’s terms and his strong desire to reach out and educate people about the climate crisis are a lasting part of his legacy,” Gore said.
Dr. Epstein’s work sparked controversy, in part because it is harder to connect climate impacts such as extreme weather and rising temperatures to the spread of disease than to more straightforward developments such as ocean acidification. But his dogged work helped transform the popular understanding of global warming, by demonstrating how an environmental phenomenon could exact a human toll.
Raised in a progressive family in Manhattan, Dr. Epstein was advised by his pediatrician father to combine his passion for social justice with a medical career.
“No matter what you do — you can do politics, you can lead a revolution — but no matter what, be a doctor,” Andy Epstein, a nurse, recalled in an interview Tuesday, “which I thought was good advice.”
Dr. Epstein managed to do both. Living in Mozambique from 1978 to 1980 with his wife and their two children, he saw how citizens struggled to get adequate medical care in the aftermath of that nation’s bitter war of independence with Portugal.
He devoted much of his early career to providing health-care access to poor Americans. As a medical student at New York’s Albert Einstein College of Medicine, he co-led a group of medical, nursing and social work students in a federally funded project to foster community medicine. He later worked in clinics in East Boston and Cambridge, Mass.
In the 1980s, Dr. Epstein led a group of American and Russian medical students to Kenya, where epidemiologists there said they were discovering malaria at higher altitudes than ever before.
He turned his attention to how changes in Earth’s climate could affect human health, releasing a report at the 1992 U.N. Earth Summit in Rio de Janeiro that linked a cholera epidemic going on at the time in Peru to algal blooms caused by warming sea surface temperatures and nutrient discharge.
“There was a sense that physicians had a very important role to play in helping people to understand the gravity and implications of these climatic changes that were underway,” said Eric Chivian, who attended the summit with Dr. Epstein and now directs Harvard’s Center for Health and the Global Environment. Dr. Epstein co-founded the center in 1996.
Dr. Epstein went on to publish papers in prominent scientific journals on topics ranging from how warming can speed the outbreak of mosquito-borne diseases and the growth of ragweed to the connection between the rise in asthma and the soot from power plants and diesel trucks.
He also plunged into the public debate over global warming, publishing opinion pieces, giving interviews and delivering a PowerPoint lecture to investors and policymakers on the multiple benefits of reducing greenhouse gases.
“This can be good for public health, good for the security, good for the economy, and we hope it’ll stabilize the climate,” he told an audience of lawyers in a speech that aired on National Public Radio in 2007. Later he told the reporter, “Reverend William Sloane Coffin said, and I slightly paraphrase, hope is the passion for the possible.”
Paul Robert Epstein was born Nov. 16, 1943, to Nathan Epstein and Edith Hillman Boxill, a music therapist. He graduated from Cornell University with a degree in physics in 1965 and received his medical degree from the Albert Einstein College of Medicine in 1969. He earned a master’s degree in public health from Harvard in 1982.
Survivors include his wife of 44 years, Andy Gates Epstein of Boston; two children, Benjamin Epstein of New Orleans and Jesse Epstein of Brooklyn; and a sister.
Despite the contentious nature of climate research, Dr. Epstein was known for his gentle manner and the fact that he was, in the words of MIT atmospheric scientist Kerry Emanuel, “kind and very concerned with humanity.”
Even as he fell seriously ill this summer, he published four pieces in the Atlantic and continued to blog about his work.
“He knew his time was very short, and he wanted to say what he needed to say in the time he had left,” Chivian said. “His work is so important — now perhaps even more important — because there is such a lack of understanding about what’s happening globally.”