The Human Side of Global Warming

Little attention has been paid to global warming's effects on human health, but without a low-carbon change of course, they will persist.

By now, global warming has been linked to melting glaciers and ice caps, higher average temperatures, and prolonged drought. What’s not as well-known are the non-headline grabbing effects that the warming climate will have on human health.

But this week several major public health organizations are calling attention to the devastating toll that climate change will take on the health of our children, families, and communities the world over. The Senate Committee on Health, Education, Labor, and Pensions holds a hearing this morning on the public health challenges of climate change. The World Health Organization has declared the theme of this week’s annual World Health Day “protecting health from climate change.” And this week’s National Public Health Week is themed “Climate Change: Our Health in the Balance.”

In a hearing on the subject yesterday in front of the House Select Committee on Energy Independence and Global Warming, chaired by Rep. Ed Markey (D-MA), Howard Frumkin, director of the Centers for Disease Control’s National Center for Environmental Health, testified, "The science is clear that carbon dioxide does contribute to climate change…and as I have testified here today, climate change presents public health challenges."

Some of the most severe health effects linked to global warming include the following:

More illness and death resulting from heat waves.

Increased frequency and severity of heat waves will lead to more heat stroke and other heat-related illness and death. Senior citizens and children are particularly vulnerable to these effects. The world has already seen the effects of heat on human health: The summer 2003 heat wave in Europe that claimed 35,000 lives was likely made worse by global warming, and in the summer of 2007, Greece suffered a massive heat wave and record wildfires. Eleven of the past 12 years rank among the hottest on record, and the Centers for Disease Control reports that heat waves already account for more deaths annually in the United States than hurricanes, tornadoes, floods, and earthquakes combined. The death toll is projected to increase as heat waves become more frequent.

Worsening air pollution causes more respiratory and cardiovascular disease.

Air pollution worsens as temperatures increase, and higher levels of ozone smog and other pollutants have been directly linked with increased rates of respiratory and cardiovascular disease, including asthma and cardiac disarryhthmia. Pediatric asthma has already increased over the past 25 years, and global warming will only exacerbate children’s suffering. Global warming is projected to most heavily affect the level of ground-level ozone in U.S. cities in the Northeast, Midwest, and West.

Vector-borne disease infections will rise.

Currently, malaria, diarrhea, malnutrition, and floods related to climate change cause about 150,000 worldwide deaths annually, according to the World Health Organization. The range of malaria-carrying mosquitoes is spreading, too, to cooler places that have never before seen the disease, such as South Korea and the highlands of Papua New Guinea.

With warming temperatures, the breeding cycle of malaria-carrying mosquitoes is shortening, which means more mosquitoes—and malaria—each year. The same effects will likely be seen with other vector-borne diseases, such as Dengue fever, which has infected 60,000 people in one outbreak in Brazil’s Rio de Janeiro this year alone. In the United States, viruses such as West Nile, Hantavirus, and Lyme disease could increase their ranges or spread more quickly with changing weather, and formerly prevalent malaria or Dengue fever could re-emerge.

Changing food production and security may cause hunger.

Rising temperatures and varying rainfall patterns could affect staple crop production and food security, while aiding the migration and breeding of pests that can devastate crops. Farmers in the tropical developing world will likely see decreases in production. Such changes could be devastating to people in poor countries, even while some cold climate nations, such as Canada, may expand their arable land.

With the prices of wheat, rice, and other staples already rising rapidly, the developing world can ill afford any production decreases at home. In addition, more severe weather, such as monsoons or hurricanes, can destroy crops and leave entire communities without food. And if hunger wasn’t bad enough already, the Intergovernmental Panel on Climate Change recently concluded that up to 250 million more Africans could be left without potable water due to climate-related stresses within the decade.

More severe and frequent wildfires will threaten more people.

Severe heat can also increase the frequency and intensity of wildfires, which threaten homes, lives, and livelihoods, and cause poor air quality. Last autumn’s wildfires in California that displaced more than 1 million people were linked to the record southern California drought. And those were only the beginning. The Nobel Prize-winning Intergovernmental Panel on Climate Change has determined that “a warming climate encourages wildfires through a longer summer period that dries fuels, promoting easier ignition and faster spread…North America very likely will continue to suffer serious loss of life and property.”

Flooding linked to rising sea levels will displace millions.

Rising sea levels make coastal areas more susceptible to storm surges and flooding that result from severe weather. The most susceptible areas are densely populated river deltas and coastal cities in Asia—the Ganges River Delta, the Mekong River Delta, islands in the Indian Ocean and South Pacific. Just last year, almost 7 million people were displaced by flooding in Dhaka, Bangladesh, and in 2004, floods there killed more than 700. With displacement comes increased transmission of water-borne disease from stagnant water, the challenge of feeding and sheltering the displaced, sewage backups and squalid conditions, and strained disaster relief resources.

In the 1990s, more than 600,000 deaths occurred worldwide as a result of weather-related disasters. WHO now says that 150,000 deaths annually are attributable to the effects of climate change. Further, as Congresswoman Hilda L. Solis noted at the House Select Committee hearing on global warming and public health, these effects “will disproportionately affect the sick, poor, elderly, and communities of color." Solis urged her "colleagues to recognize the relationship between our climate and health and to work toward achieving climate justice.” Earlier this week Solis and Markey introduced a resolution in the House, and Sen. Bernie Sanders (I-VT) a similar one in the Senate, that calls attention to the public health effects of global warming.

These human effects are real and immediate, but they can also be lessened if the United States takes the lead in transitioning to a low-carbon economy and reducing our greenhouse gas emissions now.

While the Bush administration has tried to suppress information regarding the human health consequences of its lax approach to climate change, a 2004 EPA internal memo affirmed that “climate change has global consequences for human health and the environment.” Four years later, there is still a lack of decisive action in the United States. The Senate has a golden opportunity to act when it considers the Lieberman Warner Climate Security Act in early June. But the signs are clear. We can’t afford to wait any longer.

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Daniel J. Weiss

Senior Fellow