Climate change hits hardest in low-income tropical and subtropical countries, but the people most affected aren’t defined by geography alone. Age, gender, income, occupation, and cultural ties to the land all shape how severely someone experiences rising temperatures, extreme weather, and shifting ecosystems. The burden falls disproportionately on those who contributed least to the problem.
Low-Income Countries Bear the Highest Death Toll
The gap between rich and poor nations is stark. Average mortality from floods, droughts, and storms is 15 times higher in the most vulnerable countries, such as Mozambique, Somalia, Nigeria, Afghanistan, and Haiti, compared to the least vulnerable, including the UK, Canada, and Sweden. Even in moderately vulnerable nations like India, Pakistan, and the Philippines, death rates from these events run nine times higher than in the safest countries.
A 2025 Global Climate Risk Index ranking 188 countries placed a cluster of African nations at the very bottom: Angola, Burundi, The Gambia, Guinea-Bissau, Eritrea, Lesotho, Malawi, South Sudan, Sudan, and Zambia. These countries share a combination of high exposure to climate hazards and limited financial resources to prepare for or recover from them. Paradoxically, their absolute economic losses from disasters are lower than those of wealthy nations simply because they have less infrastructure and wealth to lose in the first place. The damage is measured in lives, not dollars.
Recovery in these settings is painfully slow. Studies following communities hit by Hurricane Katrina in 2005 and Hurricane Mitch in 1998 show that poorer populations require sustained, long-term investment not just in physical rebuilding but in community organization and mental health support. Without that, the effects of a single disaster can ripple through a generation.
Children and Older Adults Face Unique Risks
Climate change affects people differently depending on where they are in life. Pregnant women, newborns, infants, children, and older adults are all considered especially susceptible to extreme heat and degraded air quality.
For young children, the danger is developmental. A baby’s organs, including the brain, are not fully formed at birth and grow rapidly in the first two years. Exposure to extreme heat and air pollution during this window can interfere with neurodevelopment, potentially affecting learning and cognitive function for years to come. Older adults face a different set of brain-related risks: reduced cognitive function linked to air pollution, along with higher rates of depression and post-traumatic stress disorder after climate disasters.
Despite this, few adaptation plans specifically account for the needs of these age groups. Most climate resilience strategies are designed around working-age adults, leaving the youngest and oldest populations underserved.
Women in Developing Countries
In sub-Saharan Africa, women make up over 60% of the agricultural workforce and are responsible for roughly 80% of food production. That deep dependence on climate-sensitive work means shifting rainfall patterns and prolonged droughts hit women’s livelihoods first. Across low- and middle-income countries broadly, an estimated 80% of women are grappling with the consequences of climate change in some direct way.
The effects extend well beyond farming. In drought-affected parts of Kenya, women and girls now walk up to 30 kilometers to find water, more than three times the distance they previously traveled. That time spent collecting water pulls girls out of school and puts women at greater risk of violence. Climate disasters also disproportionately displace women, pushing them into precarious living conditions where exploitation is common.
Outdoor Workers, Especially Farmworkers
Rising temperatures turn outdoor jobs into health hazards. In the United States, higher temperatures significantly increase workplace injuries among outdoor laborers, a population that skews toward low-wage workers from minority communities. Farmworkers are 35 times more likely to die from heat stress than workers in other occupations.
A study of heat-related deaths in California identified 6,145 deaths among outdoor workers over the study period, spanning agriculture, construction, and transportation. In counties that reported these deaths, the average annual rate was about 0.91 per 100,000 residents. These numbers reflect a state that actually has an outdoor heat standard on the books. In regions without such protections, the toll is likely higher.
Indigenous and Arctic Communities
For Indigenous peoples in the Arctic, climate change is not a future projection. It is reshaping daily life right now. Diminishing sea ice, thawing permafrost, more frequent storms, and wildfires are disrupting food security, safety, and cultural practices that have sustained communities for centuries.
Hunters in Utqiaġvik, Nuiqsut, and Kaktovik now spend twice as many days hunting bowhead whales in open water compared to 40 years ago, because sea ice seasons have shortened dramatically. Walrus hunters on St. Lawrence Island report traveling as far as 100 miles in small boats to reach animals that were once accessible much closer to shore. Traditional on-ice hunting routes around Shishmaref are no longer safe to use. In 2022, a tundra lake near Kotzebue, Alaska, that supplied freshwater to local residents abruptly drained.
For Inuit communities, food security is not simply about calories. It is deeply tied to culture, health, environmental stability, and the ability to make decisions about one’s own resources. When ice disappears and animal migration patterns shift, it threatens an entire way of life that cannot be replicated elsewhere.
Tropical Populations and Expanding Disease
Mosquito-borne diseases like dengue, Zika, and chikungunya have historically been confined to tropical regions. Rising temperatures are changing that. The viruses that cause these diseases spread faster in warmer conditions: mosquitoes become infectious more quickly, and infection rates climb as temperatures increase toward roughly 30 to 31°C. Climate models project that the potential for dengue epidemics will grow in temperate regions over the coming decades, particularly during summer months.
For people already living in tropical and subtropical areas, transmission is possible during most months of the year. The populations most affected are those without reliable access to healthcare, mosquito control, or adequate housing. A bout of dengue that might mean a few miserable days for someone with good medical care can be fatal for a child or elderly person in a community without a nearby clinic.
Climate Displacement Is Already Underway
The World Bank projects that by 2050, just over 216 million people could be forced to move within their own countries to escape slow-onset climate impacts like water stress, crop failure, and sea level rise. That figure spans six major regions: sub-Saharan Africa, East Asia and the Pacific, South Asia, North Africa, Latin America, and Eastern Europe and Central Asia. It represents about 3% of those regions’ combined population.
Central Asia alone could see 1.7 to 2.4 million internal climate migrants by 2050, depending on how aggressively nations pursue climate and development policies. In the Kyrgyz Republic, up to 200,000 people (nearly 4% of the population) could be displaced under the worst-case scenario. These are not people fleeing a single catastrophe. They are gradually leaving areas where farming no longer works, water is no longer available, or coastal land is disappearing.
The World Bank’s analysis also highlights something important: these numbers are not locked in. Under more climate-friendly and inclusive development scenarios, the number of displaced people drops by 20 to 25%. The communities most affected by climate migration are the same ones that benefit most from early investment in adaptation.