Climate in Crisis

The School’s faculty, students, and graduates are fighting the most urgent public health emergency our generation—and future generations—may ever face, and rallying peers worldwide to do the same.

October 31, 2019

Kate Weinberger thought she had her academic career all figured out. It was 2009 and she was on her way to becoming an ecologist with a master’s degree from Columbia University’s Department of Earth and Environmental Sciences. Then an elective survey course, Public Health Impacts of Climate Change, offered through the Columbia Mailman School, inspired a new path.

The following year, she enrolled in the School’s newly launched Climate and Health Program, the first of its kind in a school of public health. Five years later, she became its first PhD recipient for a dissertation on how NewYork’s changing tree pollen levels affect allergic diseases such as asthma. (A warmer, wetter climate extends the pollen season for some species.)

Right after her graduation in 2015, Weinberger spoke at a White House summit on the health impacts of climate change. “I came late to public health,” she says. “But I took one course and was totally sold on the concept. There’s a real need for research on how climate change impacts health, which people and communities are going to be most affected, and how to protect health as temperatures continue to rise.”

Weinberger watched Columbia Mailman School’s Climate and Health Program grow from a small initiative in the Environmental Health Sciences Department into a multibranch initiative that has incubated a growing cadre of researchers doing cutting-edge, cross-disciplinary science. Today, it partners with other Columbia institutions, including the Earth Institute, the International Research Institute for Climate and Society, the NASA Goddard Institute for Space Studies, and the Columbia Climate Center. As the program has grown, it has expanded its work to found the Global Consortium on Climate and Health Education (GCCHE), which is leading health-professions schools worldwide to train future leaders in climate-related issues. “It is critical that we—the public, scientists, government officials, corporations—view the effects of climate change through a public health lens,” says Jeffrey Shaman, PhD, a professor of environmental health sciences and the director of the Climate and Health Program since 2017. “The fires, floods, extreme storm events, sea level rise, and rising temperatures we are witnessing are already profoundly affecting human health and well-being. If we are to tackle these issues, we urgently need experts versed in these multidisciplinary issues who can effectively communicate their complexities to politicians, governments, corporations, and the public.”

In his commencement speech at Columbia Mailman School last May, former Vice President Al Gore noted that “the leadership of the Mailman School in acknowledging the crisis has been followed by many health experts around the world.”The need for continued leadership will only grow more urgent. The United Nations Intergovernmental Panel on Climate Change, among other experts, has warned the world that, absent “unprecedented” changes to the global economy, severe impacts of the warming planet will take place as soon as 2040, well within the lifespan of much of the world’s population. The public health effects are already layered and complex: Increased ozone air pollution results in 4.2 million premature deaths annually according to the World Health Organization (WHO). Outbreaks of infectious diseases like Zika, malaria, and dengue fever are emerging in new hot spots. Extreme and more frequent floods and rainstorms in some regions and droughts and wildfires in others are increasingly deadly. Food security will become a more significant issue as temperatures and carbon dioxide levels rise, leading to decreased protein in crops such as barley, rice, and wheat. Many of the negative effects fall disproportionately on poorer populations, older adults, and children, and they strain countries lacking the resources to address them.

Shaman points to the Lake Chad area in central Africa, where the population is among the poorest on the planet, as an example of the devastating impact of climate change on health, poverty, and political instability: Increasing temperatures and a 50-year drought dramatically reduced the lake’s size. The fishing industry turned to agriculture, which accelerated the drying of the lake. The resulting food insecurity has helped fuel the rise of Boko Haram and the Islamic State in the region, and nearly 10 million people, or half the population, now need humanitarian assistance according to the United Nations. Climate change is not the only driver of this crisis, Shaman says, but it is a significant part of the stressors that incite societal conflict and, ultimately, collapse. “How are we going to anticipate the next Lake Chad and deal with it while it’s happening?” he asks.

The widespread impact of climate change on human health was just beginning to be understood when the Columbia Mailman School Climate and Health Program launched. Ten years ago, examining the health effects of climbing temperatures was novel research. Now, it’s clear that poor health and deaths result not only from heatstroke, but also from cardiovascular disease, respiratory disease, and cerebrovascular disease exacerbated by extreme heat resulting from climate change. And that is just one of the many ways that climate and health interact.

In many regions, the effects of climate change are cascading, piling atop one another. That’s why researchers feel Columbia Mailman School’s interdisciplinary approach is critical. “We cannot only look at one air pollutant or one weather variable like temperature,” says Marianthi-Anna Kioumourtzoglou, ScD, an assistant professor at the School. Kioumourtzoglou is an environmental engineer and air pollution epidemiologist who uses computer modeling to examine how climate change drives air pollution and how that impacts health, including mental health. “We are beginning to increasingly understand there is a need to look at many things together,” she says. “It’s not just air pollution and temperature, but also snowstorms and hurricanes and coastal storms and flooding. Some are becoming more intense. Some are becoming more frequent. We are exposed to all of these together in a changing climate and we need to understand how this changing system impacts human health.”

In the early years, research efforts in the Climate and Health Program were focused in areas like air pollution, infectious disease spread, and the effects of extreme heat. In recent years, as the faculty and the student body have expanded, so has the research. Like Weinberger, students and faculty often come to Columbia Mailman School interested in one subject and find their focus pulled in exciting new directions, thanks to collaborations. Shaman notes that even seemingly unconnected issues, such as construction, urban development, and agricultural practices, can be viewed through the kaleidoscope that is climate and public health.

For Shaman, a leading expert on flu forecasting, research is inherently interdisciplinary. His work draws on virology, epidemiology, infectious disease, mathematical modeling, statistics, and atmospheric science. He examines how meteorology affects human health, notably the seasonality, transmissibility, and survival rates of influenza, as well as the effects of heat and humidity exposure indoors. “Many other climate impact studies, including examination of the effects of drought on crop yields, food insecurity, and, consequently, economic insecurity, forced migration, and conflict, also can only sensibly be examined through an interdisciplinary lens,” he says.

Kioumourtzoglou also brings together a multitalented team of experts for her projects. She is looking at how short-term exposure to high temperatures affects heart attacks and the influence of neighborhood factors, like green space and building size, on both climate and health. Her team includes researchers expert in temperature prediction models and in the epidemiology of stroke and myocardial infarction, as well as biostatisticians and computer scientists.

She also has published groundbreaking work demonstrating an association between long-term exposure to air pollution and the onset of depression. Using advanced modeling methods, her team was the first to show that prolonged exposure to fine particles in air pollution accelerates neurodegenerative conditions including dementia, Alzheimer’s, and Parkinson’s disease.

Darby Jack, PhD, an associate professor of environmental health sciences, came to Columbia not to work in public health, but to do postdoctoral research at the Earth Institute focusing on the economics of energy choices among the poor in develop- ing countries. The urgency of the Climate and Health Program’s mandate has a tendency to pull people in, and he soon found himself meeting with a group that included Columbia Mailman School scientists to discuss the health consequences of cook stoves that burn wood, which are a significant source of air pollution that leads to heart and lung disease in the developing world. Cook stoves emit greenhouse gases and black carbon, a short-lived pollutant that warms the climate and darkens glaciers and snowfields, accelerating their melting. “Air pollution and climate change are interlocking problems,” he says. “There’s a growing sense that there is a real opportunity for a public health dual win if we can address both of these problems in the same framework.”

Daniel Carrión, PhD ’19, entered the program in 2014 as a doctoral student and eventually built on Jack’s work. One aspect of his research involved better understanding the biology of pneumonia, a major killer of children that is linked to household air pollution. He looked deeper at what causes cases of pneumonia that are associated with household air pollution, finding evidence that the illness is bacterial rather than viral. This discovery could lead to better treatments or public health interventions. While there are vaccines for certain causes of bacterial pneumonia, for instance, there may be subtypes that have been missed.

Like the others, Carrión has collaborated across disciplines. “When I came into the program, I knew I wanted to be able to bridge the social and biological sciences,” he says. “There’s a lot of opportunity here to do that. The faculty encourages us to find ways to work together.” Jack says additions to the faculty and an increase in students have expanded research interests and created more opportunities for serendipitous collaborations. “Right now, the core of the program is a community of young scholars, PhD students, and postdocs who collaborate and learn from each other and, frankly, I’m learning a lot from them,” he says.

In addition to training academic researchers, Columbia Mailman School’s Climate and Health Program is helping to build a workforce to better understand climate and health and create solutions in the areas of policy, health systems, and care. Some graduates, like Kate Weinberger, go on to teach other climate scientists. (She recently joined the faculty at the University of Brit- ish Columbia, where her research will focus on the health effects of extreme heat.) Others sign on with consulting firms, work for city or state governments, or join the Centers for Disease Control and Prevention or WHO.

The number of students seeking a certificate in the Climate and Health Program has grown, reaching 22 in the 2018-2019 academic year, and the program is averaging nine doctoral students per year. The Environmental Health Sciences department recently expanded by 13 new members, including those with expertise in plant physiology, infectious diseases, and epidemiology, with a parallel growth in course offerings. Other schools are beginning to follow the Columbia Mailman School’s lead. The University of Washington started a climate and health program in 2014, and the University of Miami and the London School of Tropical Medicine and Hygiene launched their versions in 2019.

Columbia Mailman School cemented its leadership role in climate and health in 2017 when it launched GCCHE, a network of health professions schools and programs focused on training medical, nursing, and public health students, and others to prevent, reduce, and respond to the health impacts of climate change. Proposed and endorsed at the Paris Climate Accords, and then recommended as a key climate and health initiative by WHO, the consortium has nearly 200 members in 30 countries and is growing, adding schools from South Africa, Australia, and Finland in recent months. Schools pledge to educate tomorrow’s leaders on the health impacts of climate change, and GCCHE is a flourishing virtual town square, where educators exchange scientific and educational best practices. GCCHE tracks and shares innovative ways institutions are integrating climate and health content into their curricula and convening webinars to discuss strategies, challenges, and success stories. It has also developed a set of core competencies in climate and health education. Schools are responding. At the University of Cape Town School of Public Health and Family Medicine, a one-hour session is now dedicated to climate change and a two-hour session covers environmental health. “GCCHE is helping to close the knowledge gaps,” says Brittany Shea, the project director for GCCHE. “More investment needs to be put into preparing for the health impacts of climate change, and that means making sure health professionals are trained on the topic.”

Shaman is heartened by the fact that media coverage has begun focusing on the public health effects of the climate crisis, with recent stories about how warming temperatures are fueling the spread of Lyme disease being one example. As Gore told his commencement audience, “Every day in the news is dire. Every night on television is like a nature hike through the Book of Revelation.”

Adds Shaman, “There’s a new urgency that stems from the recalcitrance and inaction of the world community. It is not addressing climate change effectively.” Lyme disease looks tame compared to what is to come. “We will see increased displacements of people due to drought, agricultural failure, and sea level rise that will impose enormous health burdens on those populations and places to which they migrate. And, as is unfortunately common, the poor and disenfranchised will suffer the most.”


Jim Morrison lives in Norfolk, Virginia, where flooding related to climate change is drawing toxins into local waters. His stories have appeared in Smithsonian, The New York Times, The Wall Street Journal, Pacific Standard, and The Washington Post.