Climate Change Harms Human Health

AP Photo/Schalk van Zuydam

by Lauren Simenauer, in a Science Progress cross-post

Delegates from 194 parties are meeting in Durban, South Africa, for the annual U.N. Conference of Parties, or COP, climate change conference. Among topics being addressed is the reduction of carbon emissions worldwide, clean energy funding in lower-income nations, and the future of the Kyoto Protocol. One lesser-discussed issue that diplomats will address is the growing body of science about the impacts of climate change on global health.

The National Resources Defense Council, or NRDC, identified six natural disaster events thought to be exacerbated by climate change. Those events include ozone air pollution, heat waves, the spread of infectious disease, river flooding, hurricanes, and wildfires. Tragically, extreme weather ravaged Durban itself just days before international delegates arrived. Torrential rains caused severe flooding that destroyed 700 homes and resulted in the deaths of 10 people. But beyond the immediate effects, all these disasters have wide-reaching consequences for national health, and a study published in Health Affairs magazine estimated that health costs incurred from the tragedies exceeded $14 billion from 2000 to 2009.

In the national debate on health care, it is imperative that the international community and our lawmakers at home not ignore the value of preventing the damage that climate change will cause to both the environment and human health.

The whole story

In a 2003 report, the World Health Organization, or WHO, posited that perhaps not all effects of climate change will be detrimental. Milder winters in temperate areas might mean a decrease in the death toll during the coldest months. Further, higher average temperatures in tropical areas could kill off mosquitos that carry deadly infectious diseases.

The WHO was careful to note that human vulnerability to climate change depends on population density, economic stability, food availability, income distribution, and various other mitigating factors. Thus, it is possible that not everyone will suffer uniformly. The WHO concluded, however, that on the whole, the ill effects of climate change will disproportionately affect lower-income regions and nations compared to post-industrial nations. The disadvantages to global health, the WHO concluded, will outweigh the few potential perks of climate change.

Direct impact

The immediate effects of climate change on human health are perhaps clearest. It is no secret that heat causes dehydration and that carbon emissions result in air pollution. The Centers for Disease Control, or CDC, noted that heat waves account for the highest proportion of weather-related deaths annually, with children and older adults most susceptible. The CDC estimated that heat-related deaths could climb from about 700 a year to between 3,000 and 5,000 by the year 2050, given expected levels of human-caused warming. In order to counteract the loss to human life, the CDC recommended air conditioning for poorly ventilated areas, though such utilities are hard to come by in the lower-income areas that need them most.

The Environmental Protection Agency, or EPA, reported that an increase in particulate matter will exacerbate respiratory diseases. While some air pollutants may occur naturally, as in the case of volcanic ash and dust, there is reason to believe that a significant portion of particulate matter in the air is anthropogenic—that is, humans produce them by burning fossil fuels. NASA estimates that humans cause at least 10 percent of aerosols, a particularly hazardous type of air pollution that contributes to the greenhouse gas effect and the deterioration of human health. An increase in ground-level ozone is also associated with decreased lung function, as well as cancer.

The CDC elaborated on potential detriments to asthma and airway diseases; fine particles in the air are associated with heart attack and blood clots. Indirectly, early flower blooming increases pollen, which can cause allergic reaction. Higher temperatures also increase mold spores, further irritating respiratory diseases. Furthermore, more frequent droughts may lead to increase in airborne dust, and increasingly frequent wildfires caused by climate change may also contribute to particulate matter.

A January 2010 report from the EPA offered a conservative estimate that heat waves cost the public $5.1 billion a year in health costs. The EPA put the baseline cost for asthma and respiratory illness at $5 billion. Additionally, the EPA estimated that public health costs incurred by poor indoor air quality and communicable respiratory diseases could exceed $10 billion.

Natural disasters

With climate change comes extreme weather: more frequent and severe flooding, storms, and forest fires. The 2007 report of the Intergovernmental Panel on Climate Change, or IPCC, found that the number of hurricanes had increased annually since 1970, writing, “There is observational evidence for an increase of intense tropical cyclone activity in the North Atlantic since about 1970, correlated with increases of tropical sea surface temperatures.”

The IPCC went on to predict an influx of hurricanes in the near future:

Based on a range of models, it is likely that future tropical cyclones (typhoons and hurricanes) will become more intense, with larger peak wind speeds and more heavy precipitation associated with ongoing increases of tropical SSTs. There is less confidence in projections of a global decrease in numbers of tropical cyclones. The apparent increase in the proportion of very intense storms since 1970 in some regions is much larger than simulated by current models for that period.

The cost to human life from extreme weather is significant. Scientists and economists from the NRDC estimated that Florida hurricane season racked up $1.4 billion in health bills in 2004 alone. California wildfires cost $578 million in 2003, and flooding in North Dakota cost $20 million in 2009. Many of these figures do not take into account the added cost of damage to hospitals and other health care infrastructure, as well as the costly effects to health that pervade the population years later in the form of heart disease, cancer, and disorders of mental health.

Implications for disease control

As the globe heats up, the outlook for the containment of pathogens is becoming increasingly dismal. Rising average temperatures worldwide expand the range and seasonality of communicable diseases unique to warmer months. The WHO estimated that climate change was responsible for 2.4 percent of deaths from diarrhea and 6 percent of deaths from malaria in middle-income countries in the year 2000.

The Commission on Climate Change and Development, or CCCD, emphasized the importance of containing the rise of vector-borne diseases. Though the WHO does not predict that climate change will incite the mutation of new diseases, climate change could precipitate the resurgence of diseases that have plagued human history. Aside from malaria and diarrheal diseases, the CCCD warned of an influx of cholera, which is linked to low river flows in the dry season, and possibly due to pathogen infection of standing pools of water that result. Also of concern is an increase in rodent-borne diseases after flooding, and meningitis is linked to drought and heat, though the mechanism for transmission is still unclear.

Dengue fever and a spike in food-borne illnesses could also result from continued climate change, according to the same WHO study. A report from the National Institutes of Health, or NIH, suggested that an increase in temperatures will result in more contamination of crops. The NIH also reported that drought increases the prevalence of insects and other pests that can hamper agricultural productivity.

Of particular concern is the seafood supply. The CDC warned that algal blooms are known to release harmful neurotoxins that cause death in humans; marine organisms can also pick up these neurotoxins. The most common neurotoxin that blue-green algae releases is anatoxin-a, which interrupts neurotransmitter activity at neuromuscular junctions and can cause muscle paralysis and even death from respiratory failure. Because cooking seafood does not necessarily kill harmful biotoxins, these harmful chemicals pose a unique threat to the food supply. Measures to prevent contamination of the food supply may not be consequential, however, as the CDC reports that it is also possible that marine neurotoxins will be aerosolized by the surf crashing onto the beach and dispersing into the wind.

Communicable diseases are only the tip of the iceberg when it comes to health impacts of climate change, according to the CDC. With increases in temperatures comes an increase in the volatility of certain dangerous chemicals associated with cancer. Such hazardous chemicals like ground ozone, black carbon, diesel exhaust, and ammonia, are also known to be dispersed with heavy rainfall, which is associated with climate change. Further, the depletion of ozone means that more harmful UV radiation penetrates the atmosphere, increasing the occurrences of skin cancer.

The ripple effect

The direct consequences of climate change on public health are not relegated to the immediate effects of hotter averages and more extreme weather. The direct effects of extreme weather, like injury, property damage, and loss of life also create ripple effects that cause additional damage to society and public health. For example, the CDC warns that diminished access to food and water caused by drought could cause migration from rural to urban areas or vice versa. Migration itself is linked to health problems that impose a steep price tag for public funds. The International Organization for Migration reported that, among other health concerns, migration increases physical trauma and spreads diseases.

Additionally, climate-enhanced food insecurity has its own ramifications for human development. Starvation leads to malnutrition in mothers and, consequently, stunted development in fetuses and children.

Coastal flooding and pollution could impair food manufacturing and health care facilities. Reactions will vary regionally, but the consequences of population displacement, as well as the erosion of food manufacturing industries, may not be apparent for several decades.

Climate change is no longer just a looming threat in the abstract. Climate change is a hidden culprit with real impacts on health care costs, and, more gravely, human lives. Finding solutions to the climate crisis is no longer just an environmental issue. The effects of climate change permeate through all facets of human life, and preparing for the impact on health care should be a priority.

Lauren Simenauer is an intern with Science Progress and a senior at the University of Virginia. This piece was originally published at

10 Responses to Climate Change Harms Human Health

  1. quokka says:

    And some places will just become damned hot and possibly dangerously hot. The Australian Climate Commission projects Darwin to go from an average 9 days per year over 35C (95F) in 2008 to 312 days a year in 2100.

    How many people would really want to live in such a climate?

  2. Spike says:

    The Met Office has a report on potential impacts around the world

  3. Wes Rolley says:

    I hope that the citizens of Beijing continue to speak out. Today, we have our first Spare the Air day of the winter in the San Francisco Bay area. No burning of wood allowed: not fireplaces, not fire pits on the patio, not pellet stoves, not backyard barbecues. That is for health reasons and our air is nowhere near as bad as Beijing’s.

    When you consider all sources, air pollution costs California over $20 Billion / year.

    Some politicians want to remove all restrictions from business to grow the economy, but we can’t afford to do that if it adds to the pollution costs we have now.

  4. Leif says:

    And of course there is just plain old daily stress that sensitive people endure exposed to the facts of impending doom in there life time and certainly of their children. Couple that with being so personally helpless to effect solutions and change and you get serious health problems. Quite likely the primary sub conscious motivation to not want to expose themselves to the knowledge needed to effect the change required. All Capitalized on by the ecocidal fossil industry and lackeys that incessantly spoon feed them “feel good” pablum.

  5. Jeff Huggins says:

    Climate Change Also Harms Human Integrity

    The fact of climate change, the dilemma it presents, and our unwillingness to deal with it, when taken together, harms human integrity. What do I mean by this?

    Because “it” causes so many of us to lie to ourselves and to each other, and because we persist in the activities that are causing climate change and thus are causing (and will cause) harms to others, we (humans) are revealing our own characters to ourselves, and we’re reducing ourselves, and we are starting to feel the discomforting and integrity-killing results of that.

    Put another way, if a person goes out into the world, is honest with others, witnesses honesty in others, helps others, and doesn’t harm others, that person can feel good about himself or herself and about humankind. Of course, these things are all matters of degree, but being honest and witnessing honesty, and being responsible and witnessing responsibility, are all good things for a genuine feeling of human integrity. In such situations, one can feel good about himself and about humankind.

    But if a person is dishonest with others, and witnesses a lot of dishonesty in others, and if a person continues actions that harm others, and does not act to end those actions, and if we all witness each other continuing such harm-causing actions, the reverse happens. We feel bad about ourselves and about humankind, and rightly so.

    Perhaps a better way to put it is this (because climate change itself does not kill or harm integrity): In the face of the climate change problem, the “response” (or mainly lack of response) on our human parts is diminishing human integrity. The lies, deceptions, twisted thinking, inaction, continuing actions that are harmful, and injustices are revealing to us — and indeed establishing — an amazingly low degree of human integrity.

    And this happens everywhere, even among people who are doing quite a bit — but not really what they *should* be doing (and many know it) — with respect to climate change: Scientists who find it inconvenient or risky to their careers to join Jim Hansen in his activism. Reporters who know the vital reality of climate change, or at least pretend they do, but (for whatever reasons) succumb to the confused mud-wrestling, controversy-based approach to journalism, in the name of so-called “balance”. Issue organizations, or think-tanks, that for structural (and other) reasons are married, in effect, to a political party and thus will not do anything to genuinely challenge, where it counts (with votes), that party, or to even imply such a challenge, and to even raise discussions that might explicitly result in such a challenge. And so forth.

    So, our choices are “eating at” our integrity, and reducing it. We are witnessing an aspect of “human nature” that we don’t want to witness and that we can’t quite live comfortably with. And, the vast majority of us are complicit in this particular fault, so it’s hard to speak honestly about, because if Tom points it out in Sally, Sally can point it out in Tom. Best to stay silent about it? In any case, that’s what we’re doing, mainly: staying silent about it.

    On a related note, the word-game is growing thin, don’t you think? Here’s what I mean. Yesterday, President Obama gave a speech that was highlighted with admiration in some of the media, e.g., MSNBC. Now, I enjoyed the speech (or at least what parts I heard) as words, but we’ve heard words, ideals, and promises before. Words, words, words. And more words. What about actions? What about real courage? How am I to compare President Obama’s words, yesterday, with his decision to delay his decision regarding Keystone XL? How am I to compare his periodic comments regarding the importance of addressing climate change with the fact that he barely utters the phrase and has not, and will not, use the bully pulpit to educate the public on the matter? These are concrete questions, not theoretical.

    Dishonesty, avoidance, complicity, cowardice, and so forth all reduce human integrity — and they reveal the state of human integrity. Yikes!

    I hate to say it, but at this point, we humans really should not be feeling very good about ourselves. Actions speak louder than words. If we want to deserve to feel better about ourselves, we’ll need to make those choices, and take those actions, that will allow us to do so.

    When do we start?

    Be Well,


  6. Leif says:

    Right on Jeff, as so many of your comments are. All of which has direct health impact on all. People and animal alike. The very fabric of Earth’s life support systems for all time.

  7. Michael T says:

    NOAA: Autumn and November both warmer than average in the United States

    U.S. sets record with a dozen billion-dollar weather disasters in one year

  8. EDpeak says:

    To add another news links as Michael T did above:

    “A new report shows for the first time detailed projections of the effects of climate change on the Pacific’s 15 small island states.”

    “The three-year study by Australia’s CSIRO and Bureau of Meteorology predicts increased air and sea temperatures, more extreme rainfall days, a more acidic ocean and rising sea levels. It is the first time the island states have received an official climate change projection. ”

    “The idea is that the report will empower the island states to adapt to the effects of climate change. Considering the size of their economies it will be difficult, but….they have time”

    “There’s going to be large increases in the number of very hot days and warmer nights as well [and] there’s going to be an increase in rainfall over the region and perhaps what’s most significant is that there’s going to be more of the really heavy rainfall events.” Dr Chambers warns the changes will lead to an increase in ocean acidification and rising sea levels.

  9. NJP1 says:

    The conference in Durban may be about climate change, but as with previous CC meetings, the only positive outcome will be the date of the next meeting. (a cynic might suggest that it has become a mini vacation industry in itself). They will not accept that we are facing a triumvirate of chaos: runaway climate change, overpopulation and energy depletion. They are inseparable, and it matters not which hits us first, because that will exacerbate the impact of the other two. A conference on climate change alone takes blinkered idiocy to new heights.
    The world’s economic system (in the context of our developed ‘western’ lifestyle) has been locked into the business of producing, using and selling energy. Our economy is entirely energy based, money is just an energy-token and we have convinced ourselves that passing colored bits of paper and plastic around creates real wealth, whereas without constantly increasing energy input it is worthless. We have no other means of real employment other than to go on finding energy sources and using them to sustain our delusion of profit and growth. When it ceases, most of humanity will starve and our global numbers will rebalance themselves to sustainable levels.
    But until it does, we will go on destroying our environment because we have no option. The miner will fight to keep his job, despite knowing that coal is poisoning his land. We will not surrender our personal transport system, even though we know oil pollutes the atmosphere and biofuel denies food to starving millions. We will continue to demand cheap food, flown thousands of miles to stock our supermarkets, even though we know its production is affecting our collective health.
    We have a commercial system that demands that we burn fossil fuels at an ever faster rate to create further growth and support the delusion that we can go on dragging a ton of steel around instead of walking. Already, 50% of humanity lives in cities, with no direct access to food supplies. That fact alone should frighten our leaders into confronting our problems, but it won’t. Food has to be trucked in, and our wastes disposed of; in that respect we are little better than hamsters in a cage.
    We’ve used fossil fuel to grow our population to an unsustainable 7 billion, and 99% of out food relies on fuel burning so the earth must be ripped apart, no matter what the cost, to maintain the delusion of cheap oil, and when it’s finally gone, mankind will be facing a foodless future. This is why a climate change conference in isolation is meaningless

  10. EDpeak says:

    As you said it’s not climate change per se that is eating at integrity, but “our choices” but what’s really destroying integrity and humanity is that which LEADS to those choices.

    There is more than one single source but a main source if not the largest, is that economic force whose name dare not be mentioned. Which externalizes costs, socializes costs, and privatizes profits. Which puts profits above human needs. Which puts short term profits above even long term profits or survival. A suicidal system. It’s not just unfair and unjust (as the link in our user name shows was realized
    by John Wheatley (1907), and before) but also an anti-democratic and even suicidal system. It is our economic system, under whatever name one gives it. It must be changed if survival matters, let alone democracy and justice