A Report Signals "Code Red" on Climate Change's Impact on Human Health

A cardboard protest sign that reads "You'll die of old age we'll die of climate change."

Markus Spiske/Getty

Key Takeaways

  • This year's Lancet Countdown report warns that climate change is worsening and will exacerbate health conditions by increasing the spread of diseases, contributing to heat-related illness, and shortening the global food supply. 
  • In 2020, up to 19% of the land globally was affected by extreme drought, which led to a reduction in corn, winter wheat, rice, and soybean yields.
  • Of the 84 countries that the report reviewed, 65 were still providing subsidies to use fossil fuels, slowing the rate of carbon emission-free economies. 

This year's report in Lancet Countdown has signaled a "code red" for the world’s future. The report has found that climate change is exacerbating the health of communities across the globe.

While climate change may seem like a far-off, futuristic concept, experts warn that the changes are happening right now and that current efforts are not enough to save and preserve global health.

“Climate change is here and we’re already seeing it damaging human health across the world,” Anthony Costello, executive director of the Lancet Countdown, said in a press release

Climate Change: Code Red

“We’re seeing that across all indicators that track the impacts of climate change on human health, we see that things are getting worse,” Marina Romanello, Ph.D., research director for the Lancet Countdown and the study’s lead author, tells Verywell. 


The 2021 report—the fifth report of its kind—noted record-high temperatures in 2020 that resulted in more days of heatwave exposure for people over the age of 65 and children younger than a year old. The heatwaves led to people dying prematurely. The report also highlighted that these risks were exacerbated by a lack of access to cooling machines and urban green spaces. 


The report also found that during any given month in 2020, up to 19% of global land was affected by extreme drought. Consequently, there has been a reduction in corn, winter wheat, rice, and soybean yields, which contributes to the risk of food insecurity.

Air Quality

Climate change also poses a risk to air quality, which is largely determined by the use of fossil fuels, such as coal and gas. When fossil fuel is burned, it causes a release of carbon dioxide, which builds in the atmosphere and is responsible for the rise in global temperatures.

In 2020, petroleum accounted for 44% of fossil fuel consumption in the United States. Natural gas accounted for 43% of fossil fuel consumption—the largest annual share on record.

The extra heat that is generated gets trapped and causes air pollution and smog. Inhaling air pollutants and ozone can cause respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD).

Romanello says that this translates to "an exacerbated exposure of vulnerable peoples to air pollution, which can cause cardiovascular health impacts."

According to Romanell, countries with lower and medium levels of human development index—factors that encompass life expectancy, education, and income—had the largest increase in heat vulnerability over the past 30 years. 

Infectious Disease

Changes in conditions around the world make environments more suitable for the transmission of water, air, food, and vector-borne diseases, such as malaria, dengue, Zika, and chikungunya virus.

Who Is Most Affected By Climate Change?

Climate change will impact everyone, but our children are the most at risk.

“If we’re talking about things like food insecurity, water insecurity, children will suffer the most,” says Romanello. With anticipated food shortages, “we know that the lack of nutrition for children can have permanent effects and permanently damage their intellectual development.” 

Climate change also poses a risk to coastal communities, which rely on the synergy of water and land to live and eat. Romanello says that "rising waters are starting to take up much of the land,” which threatens to displace communities.

As a result of warming temperatures, these coastal communities are expected to experience a shortage in marine crop yield and the associated economic impacts. 

The Financial Cost of Climate Change

There’s also the economic cost of a warming world to consider. The report found that in 2020, half of the 295 billion agricultural workers lost work hours due to the heat (equivalent to 88 hours of work per employed individual). The data showed that 4% to 8% of the national gross domestic product (GDP) becomes lost as a result.

COVID-19 only exacerbated these conditions because there were worldwide lockdowns, especially in the service, construction, and manufacturing sectors. 

What Can We Do?

According to Romanello, the world is not moving fast enough to decrease carbon emissions. Of the 84 countries reviewed in the report, 65 were still subsidizing fossil fuels, slowing the progress to carbon emission-free economies.

“The concerning find is that the response of the world is not enough or commensurate to the risks that we’re facing,” says Romanello. “We’re seeing that decarbonization, since 2014 to 2018, only at 0.6% per year, which means that at this pace, would take another 150 years to fully decarbonize the world’s electricity grid. And as a consequence, increased deaths attributable to air pollution because their countries are not decarbonizing their energy systems.”

Marina Romanello, Ph.D.

The people are the power. Demand that your government accelerates action towards climate change.

— Marina Romanello, Ph.D.

According to Romanello, “there’s plenty of studies beyond ours that show that investing in our decarbonized economy is extremely cost-effective." The problem is that carbon-free economies require committed action from governments and private organizations.

That's why Romanello stresses the importance of citizens holding governments and corporations accountable, saying that "the people are the power. Demand that your government accelerates action towards climate change."

Saving The Future

In a statement provided by the White House on April 22, 2021, the U.S. government set a goal to generate a carbon pollution-free power sector by 2035 and zero net emissions by no later than 2050.

Coupled with governmental and corporate accountability, Romanello encourages people to take action in their daily lives, such as switching to more eco-friendly modes of transportation and consuming local, sustainable foods—actions that could yield greater benefits not only for the environment but for our health overall.

Marina Romanello, Ph.D.

Transitioning away from anything that harms your health and is beneficial for the environment will always be a win-win situation.

— Marina Romanello, Ph.D.

“The production of red meat has a huge environmental footprint," says Romanell. "So transitioning towards more plant-based diets can be a huge benefit to you and your health. And if you’re walking toward the bus station or train stop, it also promotes physical activity."

The bottom line for the health of ourselves and our world? As Romanello sees it, "transitioning away from anything that harms your health and is beneficial for the environment will always be a win-win situation.” 

What This Means For You

To demand action for climate change from the government, contact your local representative. You can also take individual action by reducing your carbon footprint. To calculate your carbon spending and learn how to reduce your carbon impact, visit the Nature Conservancy.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Romanello M, McGushin A, Di Napoli C, et al. The 2021 report of the Lancet Countdown on health and climate change: code red for a healthy future. Lancet. 2021;S0140-6736(21)01787-6. doi:10.1016/S0140-6736(21)01787-6

  2. U.S Energy Information Administration. U.S. fossil fuel consumption fell by 9% in 2020, the lowest level in nearly 30 years.

  3. Jiang XQ, Mei XD, Feng D. Air pollution and chronic airway diseases: what should people know and do?. Journal of Thorac Disease. 2016;8(1):E31-E40. doi:10.3978/j.issn.2072-1439.2015.11.50 

  4. The White House. Fact Sheet: President Biden Sets 2030 Greenhouse Gas Pollution Reduction Target Aimed at Creating Good-Paying Union Jobs and Securing U.S. Leadership on Clean Energy Technologies.

By Kayla Hui, MPH
Kayla Hui, MPH is the health and wellness ecommerce writer at Verywell Health.She earned her master's degree in public health from the Boston University School of Public Health and BA from the University of Wisconsin-Madison.