Climate Change and Health: The Escalating Threat of Extreme Weather Events

The intricate relationship between climate change and human health is becoming increasingly evident, with the escalating frequency and intensity of extreme weather events posing a significant global threat. A robust scientific consensus confirms that human activities are the primary driver of this climate change, leading to a surge in events such as heatwaves, floods, droughts, storms, and wildfires worldwide.1 These extreme weather phenomena have profound and multifaceted impacts on human health, manifesting both directly through injuries, fatalities, and infectious diseases, and indirectly via food and water insecurity, displacement, mental health challenges, and respiratory problems exacerbated by air pollution.4 Certain populations, due to factors like age, socioeconomic status, pre-existing health conditions, and geographic location, face a disproportionately higher risk from these climate-related health threats.4 Leading global organizations, including the World Health Organization (WHO) and the Intergovernmental Panel on Climate Change (IPCC), have extensively documented these risks, projecting a concerning future trend of intensifying extreme weather and its detrimental consequences for public health.5 Addressing this escalating threat necessitates a comprehensive strategy that encompasses mitigating climate change and implementing robust preparedness measures to safeguard human health.9

The Established Scientific Link:

The scientific community has reached an overwhelming consensus regarding the reality of human-caused climate change and its role in amplifying extreme weather events.1 Decades of rigorous research have established that the Earth’s climate has been warming at an unprecedented rate since the Industrial Revolution, primarily due to the rapid increase in atmospheric greenhouse gases, such as carbon dioxide, methane, and nitrous oxide, released by human activities, particularly the burning of fossil fuels.1 Surveys of actively publishing climate scientists consistently demonstrate a near-unanimous agreement, with consensus levels ranging from 97% to 100%, on the anthropogenic nature of this warming trend.1 This scientific understanding is not merely an opinion but is firmly grounded in extensive observational data and sophisticated climate models.2

The Intergovernmental Panel on Climate Change (IPCC), the leading international body for assessing climate change, has stated unequivocally that greenhouse gas emissions from human activities have caused significant warming of the land, oceans, and atmosphere.1 The levels of these key greenhouse gases in the atmosphere are higher than they have been in at least the past 800,000 years, and for carbon dioxide, potentially even the past 2 million years.1 The rate of increase observed since the mid-20th century is far beyond what can be explained by natural processes alone.1 Consequently, this warming trend is directly influencing weather patterns globally, making many types of extreme weather events more severe, more frequent, or more likely to occur simultaneously across different regions.1 The field of climate attribution has further advanced the understanding of this link, enabling scientists to quantify the specific contribution of human-caused climate change to individual extreme weather events, such as the increased intensity of rainfall during hurricanes and the heightened risk of extreme heatwaves.16

Types of Extreme Weather Amplified by Climate Change:

Climate change is acting as a significant amplifier for various types of extreme weather events, each with distinct and concerning trends.

Heatwaves: The frequency, intensity, and duration of heatwaves have been demonstrably increasing across the globe.1 The decade of the 2010s was the warmest on record, and many regions are experiencing longer heatwave seasons with record-breaking temperatures becoming more common.1 For instance, in major cities across the United States, heatwaves now occur three times more often than they did in the 1960s, lasting longer and reaching higher temperatures.15 The European summer heatwave of 2003, which resulted in over 70,000 deaths, was found to have had its risk at least doubled by human influence.16 Projections indicate that this trend will continue throughout the 21st century, with all regions expected to experience unprecedented levels of extreme heat.4 Warmer climates also lead to increased evaporation, contributing to drier conditions that can further intensify the impact of heatwaves.7

Floods: The intensification of the global water cycle due to climate change is resulting in more frequent and intense heavy rainfall events.1 Since 1950, there has been an observed increase in precipitation, particularly in the form of heavy rainfall, which can lead to flash floods.1 In the United States, a higher percentage of the total annual precipitation now occurs as extreme single-day events.15 With further global warming, these extreme daily precipitation events are projected to intensify by approximately 7% for each 1°C increase in temperature.9 This intensification translates to a greater risk of both pluvial floods, caused by excessive rainfall overwhelming drainage systems, and river floods, as river levels rise rapidly.9 Additionally, rising global sea levels, a direct consequence of climate change, are exacerbating the risk of coastal flooding, making low-lying areas increasingly vulnerable.1

Droughts: Many regions across the globe are experiencing an increase in the frequency and intensity of droughts, a trend linked to rising land surface air temperatures and increased evapotranspiration.1 These regions include the Mediterranean, West Asia, parts of South America, much of Africa, and Northeastern Asia.4 Projections indicate that the frequency and intensity of droughts are likely to continue increasing, particularly in areas like the Mediterranean region and southern Africa.4 The connection between heatwaves and droughts is also significant, as warmer temperatures lead to increased evaporation, causing soils and vegetation to dry out more quickly, often resulting in these two extreme events occurring in conjunction.7

Storms (including Tropical Cyclones): Evidence suggests that the strongest tropical cyclones have become more powerful in recent decades, with a documented increase in the number of severe Category 4 and 5 hurricanes in the Atlantic Ocean since 1980.9 While some projections suggest that global warming may lead to fewer tropical cyclones overall, the expectation is that those that do form will be more intense, larger, and longer-lasting, accompanied by increased precipitation.7 The average and maximum rainfall rates associated with tropical cyclones are expected to increase in a warming world.9 The proportion of intense tropical cyclones (categories 4-5) is projected to rise globally with increasing global warming.9 While there is lower confidence in past trends for severe convective storms like tornadoes and hail due to data limitations, there is high confidence that the average and maximum rain rates associated with these storms will increase in some regions.9

Wildfires: The frequency of large wildfires has increased, particularly in the American West, since the mid-1980s.9 The most significant increases have been observed in the northern Rockies and northern California.12 Scientists project that a warmer climate could lead to a substantial rise in the average area burned by western wildfires annually.12 This trend is driven by increased temperature extremes, which elevate the weather-induced risk of extreme fire seasons.16 Furthermore, the increasing co-occurrence of heatwaves and droughts creates dry and hot conditions that are highly conducive to the ignition and spread of wildfires.7

Direct Health Consequences of Extreme Weather:

The amplified extreme weather events driven by climate change have a range of direct and immediate impacts on human health.

Heat-Related Illnesses and Fatalities: Exposure to prolonged and intense heat can overwhelm the body’s ability to regulate its temperature, leading to a spectrum of heat-related illnesses.6 These include milder conditions like heat cramps and heat exhaustion, but can escalate to severe and life-threatening conditions such as heatstroke and hyperthermia, which can cause organ damage and death.6 Heat stress is now recognized as the leading cause of weather-related mortality.18 Global data from 2000 to 2019 indicates that approximately 489,000 heat-related deaths occurred each year.18 Notably, major heatwaves, such as the 2003 event in Europe and the 2010 heatwave in Russia, have resulted in tens of thousands of excess deaths.10 Moreover, extreme heat can exacerbate pre-existing chronic conditions, including cardiovascular disease, diabetes, mental health issues, and asthma, increasing the risk of complications and mortality.18 Certain populations, such as older adults and children, are particularly vulnerable to the effects of extreme heat.18 Recent research has shown a significant 70% increase in heat-related deaths among individuals over 65 in the past two decades.5

Injuries and Fatalities from Floods and Storms: Flooding is a major contributor to fatalities associated with natural disasters, particularly in the United States, where drowning is the primary cause of death.25 Besides drowning, floods can lead to injuries from being struck by debris carried in floodwaters, electrocution from contact with downed power lines in flooded areas, and hypothermia due to prolonged exposure to cold water.25 Injuries can also occur during the aftermath of floods as people engage in clean-up and repair efforts.6 Similarly, severe storms with high winds can cause direct harm through falling trees, flying debris, and the collapse of structures, resulting in injuries and fatalities.3 Projections suggest a potentially alarming increase in flood-related deaths, with estimates indicating that floods could cause as many as 8.5 million deaths globally by 2050.30

Respiratory Problems from Wildfire Smoke: The increasing frequency and intensity of wildfires are leading to significant air quality issues due to the release of large quantities of smoke.6 Wildfire smoke contains fine particulate matter and other harmful pollutants that can irritate the respiratory system, making breathing difficult and exacerbating pre-existing conditions such as asthma and chronic obstructive pulmonary disease (COPD).6 Exposure to wildfire smoke can also increase the risk of developing acute respiratory infections like bronchitis and pneumonia.31

Infectious Diseases: Extreme weather events can create conditions that favor the spread of infectious diseases.6 Flooding can contaminate water sources with sewage and other pathogens, leading to outbreaks of waterborne diseases such as diarrhea (including cholera and dysentery), hepatitis A and E, typhoid fever, and leptospirosis.6 Changes in temperature and precipitation patterns can also expand the geographic range and lengthen the transmission season of vector-borne diseases like malaria, dengue fever, and West Nile virus by affecting the breeding and survival of disease-carrying insects such as mosquitoes and ticks.6 Stagnant water left after floods can also provide breeding grounds for mosquitoes, further increasing the risk of these diseases.32 Additionally, warmer temperatures can promote the growth and survival of bacteria that cause foodborne illnesses like salmonella, listeria, and E. coli, and extreme weather events can compromise food safety practices.6

Indirect and Long-Term Health Impacts:

Beyond the immediate physical harm, extreme weather events have significant indirect and long-term consequences for human health.

Food and Water Insecurity: Droughts and floods can severely impact agricultural production, leading to reduced crop yields and the death of livestock.3 This can result in food shortages, increased food prices, and ultimately, malnutrition, especially in vulnerable populations.3 Droughts also diminish the availability of water for drinking, sanitation, and hygiene, increasing the risk of waterborne diseases.3 Furthermore, drought conditions can lead to a concentration of contaminants in remaining water sources, while floods can contaminate water supplies with sewage and agricultural runoff.6 Climate change, in general, affects the availability, quality, and diversity of food, thereby exacerbating existing food and nutrition crises.5

Displacement and Migration: Extreme weather events such as severe storms, floods, and prolonged droughts can force large numbers of people to leave their homes, leading to both temporary and permanent displacement.3 Displaced populations often face overcrowded living conditions in temporary shelters, with inadequate access to clean water, sanitation, and healthcare, which can significantly increase their vulnerability to infectious disease outbreaks.6 In the long term, climate change may render certain regions uninhabitable due to increasingly severe and frequent extreme weather, potentially leading to large-scale migration and its associated health and social challenges.37

Mental Health Issues: The experience of extreme weather events can have profound and lasting impacts on mental health.4 Individuals who directly experience these events may suffer from trauma, anxiety, depression, and post-traumatic stress disorder (PTSD).4 The loss of homes, livelihoods, and loved ones can exacerbate these mental health challenges.5 Even those not directly affected may experience anxiety and distress due to the increasing frequency and severity of extreme weather events and the uncertainty surrounding the future impacts of climate change.5

Respiratory Problems due to Air Pollution: The deterioration of air quality due to extreme weather events, particularly wildfires, poses a significant long-term health risk.6 Wildfire smoke contains fine particulate matter that can penetrate deep into the lungs, causing or exacerbating respiratory illnesses.6 Long-term exposure to this type of air pollution can contribute to the development of chronic respiratory conditions.6 Warmer temperatures, driven by climate change, can also increase the formation of ground-level ozone, another harmful air pollutant that can irritate the respiratory system and worsen conditions like asthma.6 Additionally, dust storms, which can become more frequent during periods of drought, can also contribute to respiratory problems.4 The burning of fossil fuels, a primary driver of climate change, is itself a major source of air pollution, contributing to higher rates of heart and lung disease.6

Disruption of Healthcare Systems: Extreme weather events can severely strain and disrupt healthcare systems, hindering their ability to respond to the increased health needs of affected populations.6 Floods and storms can damage or destroy hospitals, clinics, and other healthcare facilities.6 Transportation infrastructure, crucial for patients and medical supplies, can be damaged or blocked, limiting access to care.6 Power outages, often associated with severe weather, can disrupt the functioning of essential medical equipment and the storage of temperature-sensitive medications like vaccines.19 The surge in injuries, illnesses, and mental health issues following extreme weather events can overwhelm the capacity of healthcare systems, further compromising their ability to provide timely and adequate care.19

Populations at Heightened Risk:

The health impacts of climate change-related extreme weather events are not evenly distributed across the population. Certain groups face a significantly higher risk due to a combination of factors.

Children: Children are particularly vulnerable due to their physiological differences compared to adults.8 Their respiratory systems are still developing, making them more susceptible to the harmful effects of air pollution and wildfire smoke.8 They also have a lower body weight and higher levels of physical activity, which can increase their risk of heat-related illnesses.8 Furthermore, children are dependent on caregivers for their safety and well-being, making them more vulnerable during emergency situations and evacuations.8 Changes in pollen seasons due to climate change may also lead to more frequent and severe asthma episodes in children.8

Older Adults: Older adults are at increased risk due to a range of age-related physiological changes.8 Their bodies are less efficient at regulating temperature, making them more prone to heatstroke and other heat-related illnesses.8 They are also more likely to have pre-existing chronic medical conditions, such as cardiovascular and respiratory diseases, which can be exacerbated by extreme weather events.8 Many older adults take medications that can interfere with their body’s ability to regulate temperature.35 Limited mobility and social isolation can further increase their vulnerability during extreme weather events and evacuations.8 Tragically, data consistently shows that older adults account for a disproportionately high number of deaths during heatwaves and other extreme weather events.35

People with Pre-existing Health Conditions: Individuals with pre-existing health conditions, such as asthma, COPD, cardiovascular disease, diabetes, and mental health disorders, are particularly susceptible to the adverse health impacts of extreme weather.8 Extreme heat can worsen cardiovascular and respiratory conditions, while air pollution can trigger asthma attacks.8 People with diabetes and those taking certain medications may have a reduced ability to regulate body temperature, making them more vulnerable to heat-related illnesses.8 The stress and trauma associated with extreme weather events can also exacerbate mental health conditions.8

Low-Income Populations and Socially Vulnerable People: Socioeconomic factors significantly influence vulnerability to climate change-related health impacts.8 Low-income populations often lack access to essential resources such as air conditioning, adequate housing, and quality healthcare, increasing their exposure and sensitivity to extreme heat and other climate hazards.8 They may also reside in areas that are more prone to flooding or other environmental risks.8 These communities often have limited resources and capacity to adapt to the impacts of climate change.8 Data indicates that these populations experience higher rates of avoidable deaths.48 Furthermore, marginalized communities, including ethnic minorities, often face disproportionately higher risks from extreme weather events.7

Outdoor Workers: Individuals who work outdoors, such as agricultural workers, construction workers, and first responders, face increased exposure to extreme heat, air pollution, and disease-carrying insects and ticks.8 This prolonged exposure puts them at higher risk of heat-related illnesses, respiratory problems, and vector-borne diseases.8

Pregnant Women: Pregnant women are another vulnerable group who are sensitive to the health risks associated with extreme weather events like hurricanes and floods.8 These events can negatively impact their mental health and the health of their unborn babies, potentially contributing to adverse outcomes such as low birthweight or preterm birth.8

Indigenous Populations: Indigenous populations often have strong cultural and economic ties to their local environment and rely on traditional subsistence food sources.8 Climate change can disrupt these traditional practices by affecting the availability, safety, and nutritional value of traditional foods and medicinal plants, making these communities particularly vulnerable.8

People with Disabilities: People with disabilities often face significant challenges in preparing for, responding to, and recovering from extreme weather events.8 Emergency and evacuation instructions are frequently not accessible to individuals with learning, hearing, or visual disabilities.8 They may also have difficulties with mobility and may rely on support networks that can be disrupted during disasters, making them up to four times more likely to die in such events.29

Key Findings from Global Health and Climate Authorities:

Leading international organizations, the World Health Organization (WHO) and the Intergovernmental Panel on Climate Change (IPCC), have provided critical insights into the health risks associated with extreme weather events driven by climate change.

World Health Organization (WHO): The WHO has declared that climate change presents a fundamental threat to human health, acting as a multiplier of existing health vulnerabilities and potentially reversing decades of progress in global health.5 The organization highlights that climate change is directly contributing to a rise in humanitarian emergencies stemming from heatwaves, wildfires, floods, tropical storms, and hurricanes, with these events increasing in scale, frequency, and intensity.5 Alarmingly, the WHO estimates that 3.6 billion people already reside in areas highly susceptible to the impacts of climate change.5 Projections indicate that between 2030 and 2050, climate change is expected to cause approximately 250,000 additional deaths annually from conditions like undernutrition, malaria, diarrhoea, and heat stress alone.5 The direct economic damage to health is estimated to be between US$ 2–4 billion per year by 2030.5 The WHO emphasizes that low-income countries and small island developing states, despite contributing the least to global emissions, will bear the brunt of these health impacts, with death rates from extreme weather events in vulnerable regions being 15 times higher than in less vulnerable ones in the last decade.5 The organization also points to the significant burden of waterborne and foodborne diseases, exacerbated by climate stressors, affecting billions globally.5 Furthermore, the WHO estimates that air pollution, a factor linked to both climate change and the burning of fossil fuels, is responsible for approximately 6.7 million deaths annually and is associated with various negative health outcomes.5 To address this crisis, the WHO advocates for limiting global temperature rise to 1.5°C and leads initiatives like the Alliance for Transformative Action on Climate and Health (ATACH) to support countries in building climate-resilient and low-carbon health systems.5

Intergovernmental Panel on Climate Change (IPCC): The IPCC’s assessments provide the fundamental scientific basis for understanding the link between climate change and extreme weather events and their implications for health.9 The IPCC has concluded with high confidence that human-induced greenhouse gas emissions have unequivocally led to an increase in the frequency and/or intensity of several types of extreme weather and climate events since pre-industrial times, particularly for temperature extremes.9 Evidence for observed changes in extremes and their attribution to human influence has strengthened since the IPCC’s Fifth Assessment Report (AR5), especially concerning extreme precipitation, droughts, tropical cyclones, and compound extremes (such as concurrent heatwaves and droughts).9 The IPCC highlights that regional changes in the intensity and frequency of climate extremes generally scale with the level of global warming, with even small incremental increases in global warming (+0.5°C) causing statistically significant changes in extremes on a global scale and for large regions.9 The occurrence of extreme events that are unprecedented in the observed record is projected to rise with increasing global warming, even at a warming level of 1.5°C.9 Specifically, the IPCC has found that the frequency and intensity of hot extremes have increased, while those of cold extremes have decreased globally since 1950.9 Furthermore, heavy precipitation events are expected to become more frequent and intense with additional global warming 9, and more regions are projected to be affected by increases in agricultural and ecological droughts.9 The IPCC also notes that the average and maximum rain rates associated with tropical cyclones will increase in a warming world, and the proportion of intense tropical cyclones is expected to rise globally.9 The IPCC’s Working Group II specifically assesses the impacts of climate change on health and well-being, as well as potential adaptation solutions and their limitations.50

Projected Trajectory of Extreme Weather and Public Health Implications:

Future projections indicate a continued and concerning trend of increasing extreme weather events, with significant consequences for public health.

Future Trends in Extreme Weather Events: The Sixth Assessment Report from the IPCC underscores that the occurrence of extreme weather events is unprecedented and will continue to rise in frequency and intensity with increasing global warming.10 Heat extremes are projected to become more frequent and intense across the majority of land regions.4 Similarly, extreme daily precipitation events are expected to intensify by approximately 7% for each degree Celsius of global warming, leading to a greater risk of severe flooding.9 The land area affected by more frequent and severe droughts is also projected to expand.9 Furthermore, the proportion of intense tropical cyclones (Category 4-5) is expected to increase globally as the planet warms.9 The probability of compound events, such as the simultaneous occurrence of heatwaves and droughts, is also projected to increase.9 Even relatively small increases in global warming, such as 0.5°C, are expected to cause statistically significant changes in the frequency and intensity of these extreme events.9 Compared to present-day conditions, the intensity of extreme events could be at least double at 2°C of warming and quadruple at 3°C of warming.9

Potential Long-Term Consequences for Public Health: The projected increases in extreme weather events have dire implications for public health in the long term.5 The climate crisis could lead to an estimated additional 14.5 million deaths by 2050, with floods and extreme rainfall anticipated to be the leading cause of climate-induced mortality, followed by droughts.30 Heat-related deaths, particularly among older adults, are projected to increase dramatically even under scenarios of moderate warming.5 Over half of the excess mortality resulting from climate change by the year 2050 is expected to occur in Africa.24 Climate change is also expected to usher in an era of more frequent and intense outbreaks of both new and existing infectious diseases.29 For instance, the spread of malaria alone could put 5 billion people at risk by 2040.29 The mental health consequences of climate change, including trauma, anxiety, and depression, are also projected to become more widespread and severe.5 Furthermore, the anticipated increases in food and water insecurity will likely lead to higher rates of malnutrition and related health problems.5 Healthcare systems will likely face increasing strain due to the rising incidence of climate-related illnesses and injuries.5 Finally, the health impacts of climate change are projected to exacerbate existing health disparities, with the most vulnerable populations disproportionately affected.5

Strategies for Reducing Health Vulnerabilities:

Addressing the escalating health risks posed by extreme weather events requires a multifaceted approach that includes both proactive and reactive strategies.

Early Warning Systems: Implementing and strengthening multi-hazard early warning systems is a crucial step in reducing the health vulnerabilities associated with extreme weather.11 These systems are effective in minimizing loss of life and injury, reducing economic losses, and protecting critical infrastructure by providing timely alerts that allow individuals and communities to take protective measures.51 A well-functioning early warning system relies on four key pillars: understanding hazard and risk knowledge, monitoring and forecasting weather events, effectively communicating warnings to the public, and ensuring preparedness at all levels.51 These systems should be multi-hazard in nature, capable of providing warnings for a range of extreme weather events such as heatwaves, floods, storms, and wildfires.51 Investing in these systems is not only a humanitarian imperative but also a sound economic decision, with studies showing a significant return on investment.51 Ensuring that warnings reach at-risk populations through various channels, including mobile alerts, social media, and traditional methods like radio and television, is essential for their effectiveness.51 Heat-health warning systems, which alert medical communities and the public about impending heatwaves, are one example of a targeted early warning system that has been successfully implemented in several countries.55

Public Health Preparedness Plans: Developing and implementing comprehensive public health preparedness plans at local, regional, and national levels is vital for mitigating the health impacts of extreme weather events.11 These plans should include measures such as installing warning systems, improving health surveillance, ensuring access to safe drinking water, and enhancing drainage systems to reduce flood risks.11 Effective preparedness requires sustained investment, thorough planning, and collaboration across multiple sectors.48 Key components of these plans include establishing emergency plans, preparing supply kits, and ensuring that communities are aware of local weather hazards and risks.58 Strategies for specific events, such as heat action plans that include guidance on staying cool and access to cooling centers, flood preparedness measures that emphasize evacuation and avoiding floodwaters, and plans for managing respiratory issues during wildfires, are essential.11 Building resilient health infrastructure that can withstand extreme weather events is also a critical aspect of preparedness.6 Furthermore, public health preparedness efforts must prioritize reaching and supporting vulnerable populations who are at higher risk.11

Infrastructure Adaptations: Investing in infrastructure that is more resilient to extreme weather is a crucial long-term strategy for protecting public health.3 This includes improving drainage systems to reduce the impact of flooding, strengthening power grids to minimize outages during storms, and enhancing water management systems to better cope with droughts.3 The development of more resilient and sustainable hospitals, sometimes referred to as “smart hospitals,” is also important.6 Urban planning strategies can play a role in mitigating the urban heat island effect, which exacerbates heatwave impacts in cities.35 Implementing building codes and land-use planning that take into account the risks of extreme weather events can also enhance community resilience.11

Climate Change Mitigation: While adaptation strategies are essential for managing the immediate and near-term health risks of extreme weather, mitigating climate change by reducing greenhouse gas emissions is the fundamental solution for preventing the long-term escalation of these events and their associated health consequences.1 Transitioning to cleaner energy sources, improving energy efficiency, and promoting sustainable land use practices are crucial for reducing emissions.1 Importantly, many climate change mitigation actions, such as transitioning to cleaner transportation and energy sources, have significant co-benefits for public health, particularly through the reduction of air pollution.5 Limiting global warming to 1.5°C, as advocated by the WHO, could significantly reduce the number of people exposed to extreme heatwaves.5 Lowering overall greenhouse gas emissions will not only lessen the severity of future extreme weather but also lead to substantial improvements in global public health.38

Conclusion and Recommendations:

The scientific evidence overwhelmingly confirms that climate change is driving an alarming increase in the frequency and intensity of extreme weather events globally, posing a significant and escalating threat to human health. The direct impacts of these events, including heat-related illnesses, injuries, fatalities, and infectious diseases, are compounded by far-reaching indirect consequences such as food and water insecurity, displacement, mental health challenges, and respiratory problems. Vulnerable populations, including children, older adults, individuals with pre-existing conditions, and low-income communities, face a disproportionately higher burden of these health risks. The projections from leading global organizations like the WHO and IPCC paint a concerning picture of an increasingly hazardous future unless concerted action is taken.

To address this escalating crisis, a comprehensive and integrated approach is urgently needed. This requires a dual focus on mitigating the root causes of climate change by drastically reducing greenhouse gas emissions and implementing robust adaptation strategies to protect public health from the unavoidable impacts that are already occurring and those projected for the future. Based on the analysis presented in this report, the following recommendations are put forth:

• Strengthen and expand multi-hazard early warning systems: Invest in the development and enhancement of early warning systems that can effectively monitor, forecast, and communicate impending extreme weather events to all communities, with a particular emphasis on reaching vulnerable populations through accessible and understandable channels.
• Develop and implement comprehensive public health preparedness plans: Establish and regularly update public health emergency preparedness plans at all levels of government, ensuring they specifically address the health risks associated with different types of extreme weather events, including heatwaves, floods, droughts, storms, and wildfires. These plans should incorporate strategies for prevention, response, and recovery, with dedicated attention to the needs of at-risk groups.
• Invest in climate-resilient infrastructure: Prioritize investments in infrastructure that can better withstand the impacts of extreme weather, including strengthening healthcare facilities, water and sanitation systems, energy grids, and transportation networks to ensure the continuity of essential services during and after disasters.
• Prioritise climate change mitigation policies with health co-benefits: Implement ambitious policies aimed at reducing greenhouse gas emissions across all sectors, recognizing the significant opportunities to improve public health through reduced air pollution and a more stable climate.
• Enhance surveillance and research: Strengthen public health surveillance systems to better track and understand the evolving health impacts of climate change-related extreme weather. Support further research to improve our understanding of these impacts and to evaluate the effectiveness of various adaptation and mitigation strategies.
• Promote public awareness and education: Develop and disseminate clear and accessible information to the public about the health risks of extreme weather events and the actions individuals and communities can take to protect themselves and their loved ones.
• Foster inter-sectoral collaboration: Encourage and facilitate collaboration among public health agencies, emergency management organizations, climate scientists, policymakers, and community organizations to develop and implement coordinated and effective responses to the health threats posed by climate change.
• Address health inequities: Recognize and address the disproportionate vulnerability of certain populations to climate change impacts by targeting resources and interventions to those most at risk, ensuring that preparedness and response efforts promote health equity.

The escalating threat of extreme weather events driven by climate change demands immediate and decisive action. By implementing these recommendations, policymakers and public health officials can work to protect human health and build more resilient communities in the face of this growing global challenge.

Key Valuable Tables:

1. Table: Summary of Direct Health Impacts of Different Extreme Weather Events

Extreme Weather Type	Specific Direct Health Impacts
Heatwaves	Heat stress, heat exhaustion, heatstroke, hyperthermia, exacerbation of cardiovascular, respiratory, mental health conditions and diabetes, organ failure, death
Floods	Drowning, injuries from debris, electrocution, hypothermia, increased risk of waterborne diseases (e.g., cholera, typhoid, hepatitis), injuries during clean-up
Storms	Injuries and fatalities from high winds, falling trees, flying debris, structural collapses
Wildfires	Burns, injuries, respiratory problems due to smoke inhalation (irritation, worsening of asthma/COPD, increased risk of respiratory infections)

2. Table: Summary of Indirect Health Impacts of Different Extreme Weather Events

Extreme Weather Type	Specific Indirect Health Impacts
Droughts	Food insecurity and malnutrition due to crop failure and livestock loss, water scarcity leading to poor sanitation and hygiene and increased risk of infectious diseases, concentration of contaminants in water sources, mental health issues (anxiety, depression)
Floods	Displacement leading to overcrowding and increased risk of infectious diseases, contamination of water sources leading to waterborne illnesses, damage to healthcare infrastructure, mental health issues (trauma, anxiety)
Heatwaves	Exacerbation of air pollution (ozone formation), strain on energy infrastructure affecting healthcare services, reduced work productivity, potential for wildfires leading to respiratory problems
Wildfires	Widespread air pollution leading to respiratory and cardiovascular problems, displacement, mental health issues (anxiety, trauma)

3. Table: Vulnerable Populations and Their Specific Health Risks from Extreme Weather

Vulnerable Population Group	Specific Health Risks from Extreme Weather
Children	Increased sensitivity to heat stress, respiratory problems from air pollution, dependence on caregivers during emergencies, increased asthma episodes due to longer pollen seasons
Older Adults	Higher risk of heatstroke and other heat-related illnesses, exacerbation of chronic conditions, medication interactions affecting thermoregulation, limited mobility during evacuations, social isolation
People with Pre-existing Conditions	Worsening of asthma, COPD, cardiovascular disease, diabetes, mental health disorders due to heat, air pollution, and stress
Low-Income Populations	Greater exposure to heat and air pollution due to lack of resources, higher risk of food and water insecurity, limited access to healthcare, increased risk of displacement
Outdoor Workers	Increased exposure to extreme heat, air pollution, and vector-borne diseases, higher risk of heat-related illnesses
Pregnant Women	Sensitivity to extreme heat and weather events, potential for adverse pregnancy outcomes, mental health impacts
Indigenous Populations	Disruption of traditional food sources and practices, impacts on traditional medicines, food insecurity
People with Disabilities	Challenges with accessible information, evacuation, and support services, higher risk of mortality during disasters

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