Photo: The hood of a Ford car running with bio-ethanol is seen during the second media day of the 77th Geneva Motor Show, in March, 2007

A Ford car proudly displays its clean technology credentials on media day at the 2007 Geneva Motor Show in Switzerland. Biodiesel is made from renewable sources like soybean oil, mustard seed oil, or waste vegetable oil, which are mixed with an alcohol and a catalyst.

Photograph by Fabrice Coffrini/Getty Images

Mindy Pennybacker

Republished from the pages of The Green Guide

In the last 100 years, the Earth's average surface temperature has risen by about 1 degree Fahrenheit (0.6 degrees Celsius), and it may climb 2.5 to 10 degrees Fahrenheit (1.5 to 6 degrees Celsius) higher by 2100, the Intergovernmental Panel on Climate Change (IPCC) predicts.

Associate Director of the Center for Health and the Global Environment at Harvard Medical School Paul Epstein, M.D., M.PH., has just completed a study on how increased CO2 accelerates and increases pollen production in ragweed, which is common throughout the U.S. and Canada.

Based on this study, Epstein believes this warming, and the increased CO2 production it could cause, may mean more frequent and intense symptoms for the estimated 50 million Americans who suffer from allergies and the approximately 18 million with asthma, which is frequently triggered by allergens. According to the U.S. Centers for Disease Control and Prevention, in 1998, at least 5,438 people died of asthma in this country, and 423,000 were hospitalized for it.

Breathing Problems: "Hotter weather means more ozone, or smog, is produced from the burning of fossil fuels, and that will cause more respiratory effects," says Dr. Rosenzweig. Already, approximately half of all Americans live in areas with unhealthy ozone levels, the American Lung Association reported in May 2002.

What You Can Do

To reduce exposure to allergens and lung irritants:

• Check your local weather reports for air quality, including smog and pollen counts, before spending time out of doors. If outdoor air is polluted, keep windows closed. Exercise in early morning, before smog and pollen rise with the day's heat.

• Use a doormat to reduce tracking-in of dirt and particles. Leave shoes by the door.

• Remove carpets, in which pollutants collect, and wash area rugs.

• Use HEPA filters, which remove microscopic pollen particles, in vacuum cleaners, air-purifying machines, and air conditioners.

• Take refuge in air-conditioned bookstores, museums, cafés, or movie theaters when air is bad.

To help reduce global-warming gases:

• Choose energy-efficient electrical appliances.

• Drive less. Walk, bike, skate, or take public transportation. You'll also burn more calories (30 percent of Americans are obese).

• Ask Congress and the White House to preserve and enforce the Clean Air Act.

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