Global Warming Is Linked to 150,000 Deaths Annually: Understanding the Human Cost

Climate change is causing more than just hotter days—it drives over 150,000 deaths each year worldwide.

By Sneha Tete, Integrated MA, Certified Relationship Coach

Created on Sep 27, 2025

Climate change is causing more than just hotter days—it drives over 150,000 deaths each year worldwide.

Global Warming: A Growing Human Tragedy of 150,000 Deaths Annually

Climate change is not just about rising sea levels and melting glaciers—it is also a profound human health crisis. According to international scientific bodies and a range of detailed studies, the effects of global warming now contribute to over 150,000 deaths around the world each year, and this number is projected to grow if current trends persist.^*

How Climate Change Causes Deaths: The Science Explained

Global warming refers to the long-term increase in Earth’s average surface temperature due to human-induced emissions of greenhouse gases. It triggers a cascade of environmental disruptions, including more frequent and intense heatwaves, extreme weather events, and new patterns of infectious disease—all of which increasingly imperil human health and survival.^*

The linkage from a warming atmosphere to increased mortality occurs via several key hazards:

Heatwaves: Prolonged periods of extreme heat strain the body’s ability to regulate temperature, causing dehydration, organ failure, and even death, particularly among vulnerable populations.
Vector-borne diseases: Warmer conditions expand the habitats of disease-carrying mosquitoes and ticks, exposing more people to illnesses like malaria and dengue fever.
Extreme weather: Floods, droughts, and hurricanes—becoming more severe as the planet heats—destroy infrastructure, reduce access to clean water, displace communities, and increase fatalities.
Food insecurity: Crop failures due to erratic weather and heat reduce food supply, cause malnutrition, and lead to deaths—especially in developing countries.
Air pollution: Rising temperatures can worsen smog and particulate pollution, directly contributing to respiratory and cardiovascular deaths.

Quantifying the Human Toll: 150,000 Deaths and Rising

A growing body of research underscores how deadly the changing climate has already become. A groundbreaking study published by the World Health Organization (WHO) and confirmed by recent multinational research projects clarifies that at least 150,000 deaths per year are now attributable to the effects of global warming—ranging from heatstroke to disease outbreaks and more.^*

Key points from recent analyses:

From 1990 to 2019, an average of 153,078 deaths per year were associated specifically with heatwaves—a major consequence of global warming.
This accounts for approximately 0.94% of all deaths worldwide and equates to 236 deaths per ten million residents annually.
Projections suggest that, without bold intervention, these numbers will continue to rise throughout the coming decades as global temperatures climb further.

Where the Burden Falls: Global and Regional Disparities

Not all parts of the world are equally affected by the deadly consequences of global warming. While exposure to rising temperatures and extreme weather is global, the impact is highly uneven:

Asia: Experiences the highest number of heatwave-related deaths due to sheer population size and rapid urbanization. Nearly half of all global heatwave deaths occur here.
Europe: Although it has a smaller population than Asia, Europe has the highest rate of heatwave deaths adjusted for population, with southern and eastern regions experiencing the worst impacts.
Sub-Saharan Africa, the Middle East, & South Asia: These areas face a disproportionate risk from both heat stress and the spread of diseases that are sensitive to climate, like malaria and diarrheal illnesses.
Developing countries: Suffer more acutely due to limited resources for adaptation and healthcare. Over 85% of the climate-related health burden is found in low-income nations.

The Growing Impact of Heatwaves

Heatwaves—defined as periods of abnormally high temperatures that persist for days or weeks—are among the most deadly climate risks. Their frequency and severity are both on the rise due to global warming.

A landmark Monash University study estimated over 153,000 annual deaths globally attributed to heatwaves between 1990–2019, with Asia hardest hit.
Urban areas, where temperatures are amplified by concrete structures and a lack of green spaces, see the worst effects—a phenomenon known as the “urban heat island.”
Specific vulnerable groups include the elderly, infants, the chronically ill, outdoor workers, and people without access to cooling or air conditioning.
Europe’s devastating 2003 heatwave serves as a stark example, contributing to more than 70,000 excess deaths in a single summer.

Indirect Killers: Disease, Hunger, and Displacement

While heatwaves command headlines as dramatic causes of death, global warming also increases mortality through less direct, but equally severe, pathways:

Vector-borne Diseases: Malaria, dengue, Zika, Lyme, and other illnesses are moving into new regions as vector species proliferate in a warming climate.
Water-borne Diseases: Rising temperatures and floods increase the spread of cholera and other water-related illnesses.
Crop Failure & Malnutrition: Drought and unpredictable weather devastate agriculture, increasing child mortality due to malnutrition.
Mental Health: Disasters, food insecurity, and forced migration all drive up rates of depression, anxiety, and suicide.

Loss of Habitable Land and Biodiversity

Beyond direct human health impacts, global warming is expected to shrink habitable land and devastate ecosystems, setting the stage for even greater loss of life in future generations.

Almost 9% of the world’s population (over 600 million people) has already been exposed to unprecedented heat—conditions not previously recorded in human history.
Without major emissions cuts, one third of the global population could face unprecedented heat by the end of this century.
Biodiversity loss: As much as 70–90% of warm-water coral reefs could disappear with 1.5°C warming, and up to 99% with 2°C—threatening food security and livelihoods for millions.

Table: Estimated Global Impacts of Global Warming

Impact	Current Estimates	Projection (if warming continues)
Annual deaths from climate change	150,000+	Increasing, potentially hundreds of thousands
Annual heatwave deaths	153,000	Substantial rise with each degree increase
Populations exposed to unprecedented heat	600 million+	Up to 1/3 of humanity by 2100
Tropical coral reefs at risk	70-90% lost at 1.5°C	99% lost at 2°C

Who Is Most At Risk?

Elderly and chronically ill: Less able to regulate body temperature and more susceptible to dehydration.
Children: Particularly vulnerable to nutritional and infectious diseases exacerbated by climate change.
Low-income communities: Less able to afford adaptive measures (like air conditioning or medical care) and more likely to live in hazard-prone areas.
Rural populations: Heavily dependent on agriculture and thus at greater risk from droughts, crop failures, and water shortages.
Coastal populations: Threatened by sea level rise and flooding, sometimes forcing entire communities to migrate.

Past and Future: Is the Situation Improving or Worsening?

Despite the grim statistics, some research offers a nuanced view of the trends. For example, recent data indicate that the global heatwave-related excess death rate actually declined by 7.2% per decade from 1990 to 2019, likely reflecting improved healthcare, adaptation, and warning systems. However, the overall trend in climate-related mortality is expected to rise with ongoing emissions and higher population exposures.

Other key projections and findings:

Continued global emissions could see annual deaths from climate change multiply by the 2030s—2050s.
Every 4,000 tonnes of CO₂ emitted today is estimated to result in one additional future climate-related death.

Mitigation and Adaptation: Can Deaths Be Prevented?

Preventing climate-related deaths requires urgent action on global warming. Adaptation policies (helping communities cope with the effects) and mitigation (curbing greenhouse gas emissions) are both crucial.

Reducing greenhouse gas emissions: The quicker the world shifts to clean energy, the fewer deaths will result.
Early warning systems: Public health campaigns and alerts allow populations to take life-saving actions in heatwaves and disasters.
Infrastructure improvements: Cooling centers, green urban spaces, improved healthcare, and better water management drastically reduce vulnerability.
International cooperation: Wealthier countries can help the most at-risk populations adapt and recover, reducing global disparities.

Frequently Asked Questions (FAQs)

Q: How is the figure of 150,000 deaths annually from climate change calculated?

A: This estimate is based on statistical models using decades of data on heatwave mortality, disaster records, disease incidence, and environmental changes, creating a comprehensive picture of excess deaths attributable to global warming.

Q: Which countries or regions are most affected by climate-related deaths?

A: Asia and Africa see the greatest numbers of deaths, with lower-income and tropical countries experiencing the highest risks due to extreme heat, poverty, and limited adaptive capacity.

Q: Are heatwaves the most deadly aspect of global warming?

A: Heatwaves cause the largest share of documented direct deaths, but climate change also indirectly causes deaths via disease, famine, and disaster—these are harder to count but may eventually surpass deaths from heat alone.

Q: What groups are most vulnerable to dying from climate change?

A: The elderly, chronically ill, children, and the poor are most at risk, especially in regions lacking adequate healthcare or adaptation infrastructure.

Q: Can the death toll from climate change be reduced?

A: Yes. By cutting emissions, enhancing adaptation policies, creating warning systems, and supporting vulnerable communities, millions of future lives can be saved.

Summary Table: Key Risks and Who Faces Them

Climate Risk	Main Death Pathway	Most Vulnerable Groups
Heatwaves	Organ failure, dehydration	Elderly, urban poor, outdoor workers
Vector-borne diseases	Malaria, dengue, Zika	Children, tropical nations
Extreme weather	Trauma, infrastructure collapse	Rural/urban poor, disaster-prone populations
Crops failure	Malnutrition, starvation	Farmers, children

Sources and Further Reading

Monash University and PLOS Medicine global heatwave mortality study (2024)
World Health Organization: Climate Change and Health Fact Sheets
Carbon Independent: Mortality and Other Harms from Climate Change
Mongabay: Developing Countries and Climate Impact Forecasts
POLITICO Pro: Data Analysis of Climate-Related Deaths

References

Author

Sneha TeteBeauty & Lifestyle Writer

Sneha is a relationships and lifestyle writer with a strong foundation in applied linguistics and certified training in relationship coaching. She brings over five years of writing experience to thebridalbox, crafting thoughtful, research-driven content that empowers readers to build healthier relationships, boost emotional well-being, and embrace holistic living.

Read full bio of Sneha Tete