Climate Change Threatens Health: Air Pollution

Air Pollution: Smog, Smoke and Pollen

National Map: Air Pollution Vulnerability

Rising temperatures can make smog pollution worse and increase the number of "bad air days" when it's hard to breathe. This puts many of us at risk for irritated eyes, noses, and lungs -- but it is particularly dangerous for people with respiratory diseases like asthma. As the climate changes, unhealthy air pollution will get worse. Here's how:

Ozone smog forms when pollution from vehicles, factories, and other sources reacts with sunlight and heat. Increasing temperatures speed this process and result in more smog. Added to the mix are ragweed and other allergens in the air -- which are expected to worsen as rising carbon dioxide levels cause plants to produce more pollen. Also, as dry areas get dryer, wildfire risks go up and smoke from burning landscapes intensifies poor air quality.

iStockCarbon pollution from vehicles, power plants and other sources drives climate change, increasing ozone smog, allergens, and sending health-harming particles and toxics into the air.

Exposure to increased smog, pollen pollution, and wildfire smoke puts a wide range of people at risk for irritated eyes, throats and lung damage (the U.S. EPA likened breathing ozone to getting a sunburn on your lungs). This includes outdoor workers, children, the elderly, and those who exercise outside.

But people with asthma, allergies, and other respiratory diseases face the most serious threats, since exposure to increased pollution heightens sensitivity to allergens, impairs lungs, triggers asthma attacks, sends people to the hospital, and even results in death. In 2010, the American Lung Association estimated that about 23 million Americans suffered from asthma.

Communities must take steps to improve air quality, but everyone should know the risks that climate change poses and learn how to best protect themselves when bad air days get worse.

Eleven states and various local governments have developed preparedness measures to address the air quality impacts associated with climate change. The most frequent recommendation is developing or strengthening statewide air monitoring programs; gathering information is often the first step towards preparing for climate change related threats.

How are states addressing air pollution?

• California's plan includes identifying, tracking, and addressing climate-related vulnerabilities, such as reducing air pollution in "hot spots," and expanding asthma monitoring. Find out more >>
• Florida's plan includes strengthening current air pollution prevention policies to account for the effects of climate change. Find out more >>
• Maine's plan includes studying and assessing increased health threats from worsening air quality due to climate change. Find out more >>
• Maryland's plan includes identifying areas most at risk, improving alert and public educations systems, and working to reduce pollutant emissions. Find out more >>
• Michigan's plan includes expanding research and monitoring of air quality threats from climate change. Find out more >>
• New York's plan includes expanding surveillance of health indicators, monitoring of air quality, and making the information publicly available. Find out more >>
• New Hampshire's plan includes strengthening the ability of local emergency services to respond to days with unhealthy air quality. Find out more >>
• Oregon's plan includes measures to address forest fire emission-related vulnerabilities. Find out more >>
• Washington's plan includes reducing current air quality problems, tracking contaminant levels, informing healthcare providers, and improving public outreach. Find out more >>
• Wisconsin's plan includes tracking and responding to air quality threats. The city of Milwaukee's plan includes additional measures to reduce current levels of air pollution and improve air quality warning systems. Find out more >>
• Virginia's plan includes tracking track changes in allergic or respiratory illnesses and cardiovascular disease that might be associated with air pollution. Find out more >>

Map Methods

In NRDC's 2007 issue paper, Sneezing and Wheezing: How Global Warming Could Increase Ragweed Allergies, Air Pollution, and Asthma, pages 14-16 describe the methodology by which we created the online air pollution map on our pages. "Unhealthy ozone days" are those sites where at least one day per summer, on average, did not meet the US EPA's health-based standard for ground-level ozone smog, in the five study years from 2002-2006. The presence of ragweed in an area can mean allergenic pollen is also being produced in late summer and into autumn, which is often the same time that ozone smog is at its worst, posing a "double-whammy" to health for people with allergies and asthma.

Related Links

• Sneezing and Wheezing: How Global Warming Could Increase Ragweed Allergies, Air Pollution, and Asthma
• Heat Advisory 2004 and 2007: How Global Warming Causes More Bad Air Days
• U.S. Global Change Research Program: Climate Impacts on Human Health