The climate emergency presents a fundamental threat to human health, touching every aspect of the environment as well as human and natural systems including the functioning of health care infrastructure and the transmission of diseases — and it’s getting worse. 

According to a report published in the medical journal the Lancet in Nov. 2023, more people are getting sick and dying from extreme heat, drought, and other climate problems.

One of the starkest projections of the report was that if the global average temperature rises by 2 degrees Celsius compared with pre-industrial temperatures, an increasingly likely future, the number of heat-related deaths each year will increase by 370% by the middle of this century.

What’s more, despite contributing minimally to global emissions, low-income countries in the Global South and small island developing states endure the harshest health impacts. In vulnerable regions, the death rate from extreme weather events in the last decade was 15 times higher than in less vulnerable ones.

These are seven ways in which climate change is impacting our health.

1. It’s Affecting Our Mental Health

Both the Intergovernmental Panel on Climate Change (IPCC) report and a World Health Organization (WHO) policy brief in 2022 concluded that climate change poses serious risks to mental health from emotional distress to anxiety, depression, grief, and suicidal behavior.

Yet, there is very little dedicated mental health support available for people and communities dealing with climate-related hazards, according to Dr Maria Neira, Director of the Department of Environment, Climate Change, and Health at the WHO.

Even if you’ve never experienced a climate change-induced event such as flooding or drought first-hand, you’ve probably not been spared the existential dread that comes with knowing our planet is, in Secretary-General of the United Nations António Guterres’ words, “hurtling towards disaster, eyes wide open.”

Known as “eco-anxiety,” the psychological effect that the climate emergency is having globally on mental health cannot be underestimated. 

In a study published in March 2023 that looked at attitudes about climate change from 10,000 people across the world, almost 62% of respondents aged 16-25 said they were anxious about climate change and about 67% said they were sad and afraid.  

That’s not to mention the incalculable mental costs of experiencing the direct impacts of climate-change related disasters which can lead to posttraumatic stress disorder, adjustment disorder, and depression.

2. It’s Increasing Disease Transmission

The climate crisis is acting as a petri dish for many deadly diseases. Indeed, at least 200 infectious diseases globally are exacerbated by climate hazards.

Many food-, water-, and vector-borne diseases are sensitive to the climate which means that as global warming heats up the planet, more places around the world are now also reaching suitable temperatures for disease transmission.

Life-threatening diseases are spreading, including dengue, malaria, and West Nile virus while warmer seas have led to the coastal spread of the water-borne vibrio bacteria, putting over a billion people at risk of diarrhoeal disease, severe wound infections, and sepsis.

Warmer temperatures and increased rainfall can also increase the amount of stagnant water in an area, creating more breeding grounds for mosquitoes and ticks that carry diseases. Droughts can also support breeding by forming pools of standing water from previously flowing water.

3. It’s Wrecking Health Care Systems

Climate change not only has direct impacts on human health, but also threatens the capacity of health systems to care for people. 

Events like hurricanes and wildfires can destroy and damage health care facilities as well as leading to power outages. When hospitals are forced to close, others can become stretched beyond their capacity. 

At other times, hospitals might need to be evacuated, and damaged roads can prevent people from getting there in the first place. 

Moreover, the sheer scale of the public health crisis brought on by climate change’s impacts is overwhelming health systems. One study, for instance, found that 10 climate events in the US in 2012 totaled $10 billion in health-related costs, including hospital admissions, emergency department visits, and lost wages.

4. Air Pollution is Choking Us

Burning fossil fuels releases nitrogen oxides into the atmosphere, which contribute to the formation of smog and acid rain. Both of these phenomena are responsible for several respiratory disorders, cardiovascular dysfunction, neurological disorders, and cancer, with children and pregnant women most vulnerable.

According to the WHO, almost all of the global population (99%) breathe air that exceeds WHO-determined guidelines and contains high levels of pollutants.

A peer-reviewed study in Environmental Research released in April 2021 found that exposure to fine particulate matter from burning fossil fuels led to 8.7 million deaths globally in 2018. To put that into perspective, fossil fuel pollution is killing more people each year than COVID-19 has done since 2020.

5. Extreme Heat is Frying Us

Extreme heat is a significant public health threat around the world. Exposure can cause heat exhaustion and heatstroke, and can worsen pre-existing cardiovascular and respiratory conditions. The WHO estimated in Oct. 2023 that 37% of heat-related deaths are due to human-induced climate change.

In fact, extreme heat already kills more people in the US than hurricanes, floods, or any other weather-related emergency. Some of these deaths are the result of heatstroke, which occurs when the ambient temperature is so high that the body cannot internally regulate. Organ failure can result within minutes.

Older people in particular are especially vulnerable to extreme heat. In fact, heat-related deaths of people older than 65 have increased by 85% since the 1990s.

High temperatures can also exacerbate underlying medical conditions by straining the heart, lungs, and kidneys. A review published in Lancet Planetary Health found that heat waves were associated with an almost 12% increase in mortality from cardiovascular disease. Other researchers have noted correlations between duration of heat events and increased emergency care for kidney disease and chronic lung conditions.

6. Food Insecurity Is Costing Lives

Food insecurity is a health issue that is affecting up to 800 million people. Food is a resource that sustains existence and human health, as such, not having access to it is a direct threat to health.  In 2022, for example, almost 10% of the world was living without access to enough nutritious food — the highest number of people facing hunger in at least a decade.

The WHO estimates nine million people die every year from hunger but malnutrition also causes physical and mental development delays and disorders. Malnourished children are also more susceptible to infectious and chronic diseases.

7. Displacement Disrupts Treatment

According to UNHCR, the UN’s refugee agency, an annual average of 21.5 million people were forcibly displaced each year by weather-related events – such as floods, storms, wildfires, and extreme temperatures – between 2008 and 2016. 

By 2050, there could be 1.2 billion climate refugees. As well as losing their lives and livelihoods, for many of these people, this will mean having their medical treatment disrupted. 

“If you’re on cancer chemotherapy or if you are getting kidney dialysis or if you’re getting addiction treatment and you have to move suddenly, that’s terribly disruptive and threatening,” Dr. Howard Frumkin, a former special assistant to the director for climate change and health at the Centers for Disease Control and Prevention, told the New York Times.

If this article interested you, then you might also be interested in our latest initiative to alleviate global inequities. The Move Afrika: Rwanda campaign aims to promote stronger health systems as a pathway to promoting equity, create jobs and economic opportunity, and to call for the defense of our planet and its inhabitants. Take action with us for health systems, economic opportunity, and the planet and you could earn tickets to join us at the BK Arena in Kigali on Dec. 6. You can also purchase priority tickets directly. Here's everything you need to know about the Move Afrika: Rwanda event and campaign.

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