Climate Change & Health


At the Harvard Global Health Institute, we understand climate change is more than just an environmental issue, it is a public health emergency that is putting our health and health systems at risk. In collaboration with climate change and health experts across Harvard University and its partners, HGHI is leading public health action against climate change through innovative research, global decarbonization, health education, and strategic engagement and outreach.

We are exploring the climate change factors that impact health to develop evidence-based solutions; from supporting the decarbonization of the health sector to analyzing the cost of health services in Medicare users after extreme weather events.

Climate Change Changes Healthcare

Climate change not only impacts health but also changes the way we use our healthcare system. The increasing frequency and intensity of extreme weather events disrupt already vulnerable health systems while increasing the cost of services for both short and long-term diseases.

Dr. Renee Salas leads research that assesses healthcare utilization, outcomes, and cost of extreme weather events in Medicare beneficiaries. Her work explores population displacement and inequalities, supply chain vulnerabilities, and gaps in healthcare access with global health implications for informing evidence-based prevention.

HGHI has also partnered with The Access Challenge on the One by One: Target 2030 campaign, which is designed to drive collaboration among all African governments to achieve universal health coverage (UHC). Published on June 5, 2020, the joint report “Africa Leads the Way: Harnessing Multi-sectoral Collaboration to Achieve UHC” provides a framework for achieving UHC by 2030  and building resilience against external threats like climate change by applying multi-sectoral approaches.

Healthcare’s Contribution to Climate Change

In 2018, the National Climate Assessment reported that almost 10% of all greenhouse gas emissions in the U.S. come from the healthcare sector. Greenhouse gas emissions associated with health care have also increased over ten years by 30 percent. With climate change having the greatest impact on human health, the healthcare sector has an opportunity to protect its patients by significantly reducing its greenhouse gas emissions. Under the leadership of former HGHI Faculty Director Ashish K. Jha, Aaron Bernstein at the HGHI, and Harvard Medical School Dean George Q. Daley, all Harvard-affiliated hospitals and clinical institutes, representing more than 25 individual facilities, signed a commitment in December 2018 to reduce their carbon footprint.

In 2019, HGHI worked to support the decarbonization of health systems across the US and the globe.

Communicating a Public Health Emergency

HGHI works to foster a deeper understanding of the interactions between climate change and health through strategic engagement and outreach.

Since 2018, Dr. Renee Salas has served as the lead or senior author of the Lancet Countdown on Health and Climate Change U.S. Brief, which highlights key threats and opportunities climate poses for the health of Americans both now and in the future. In the Countdown Brief, Dr. Salas and coauthors highlight the role that hospitals can play in the transition to renewable sources of energy, as well as the need to develop and implement adaptation strategies to meet the health impacts of climate change, and the need to educate both the public and health professionals about these health impacts.

Dr. Aaron Bernstein is a climate change and health expert who testified before the House Committee on Oversight and Reform on April 30, 2019, on the public health impacts of climate change. Dr. Bernstein, a pediatrician, discussed how climate change has affected children’s health through vector-borne diseases, asthma, and mental health consequences.

Educating Health Professionals

Created with support from the Harvard Global Health Institute, health students and experts can now learn about the intersection of climate change and public health through an online, self-paced edX course titled “The Health Effects of Climate Change.” By looking at air quality, nutrition, infectious diseases, and human migration, the course demonstrates how climate change impacts people around the globe, as well as providing recommendations for how individuals can respond to and mitigate these challenges.