Ozone Shifts North: Air Quality Advisory Issued For Hudson Valley

NEW YORK — Air quality health advisories have been issued for Tuesday for Dutchess, Orange, Putnam, Rockland, Ulster and Westchester counties plus New York City by the State Department of Environmental Conservation and State Department of Health.

However, things are slightly better on Long Island than Monday, where an advisory was issued.

The pollutant of concern continues to be ground-level ozone. The Tuesday advisory will be in effect 11 a.m. through 11 p.m.

The air quality index for the Hudson Valley, at 101, is in the orange zone — "unhealthy for sensitive groups," according to the DEC.

Long Island's air didn't improve as much as expected. Tuesday's index is 80 — far higher than the 54 predicted, but still considered "moderate."

Summer heat can lead to the formation of ground-level ozone, a major component of photochemical smog. Automobile exhaust and out-of-state emission sources are the primary sources of ground-level ozone and the most serious air pollution problems in the northeast.

(This should not be confused with the protective layer of ozone in the upper atmosphere.)

People, especially those with cardiovascular disease and those who have respiratory disease (such as asthma), young children, those who exercise outdoors, and those involved in vigorous outdoor work should consider limiting strenuous outdoor physical activity when ozone levels are the highest (generally afternoon to early evening).

When outdoor levels of ozone are elevated, going indoors will usually reduce exposure. Anyone experiencing symptoms such as shortness of breath, chest pain, or coughing should consider consulting their personal physician.

New Yorkers are urged to take the following energy-saving and pollution-reducing steps:

• use mass transit or carpool instead of driving, as automobile emissions account for about 60 percent of pollution in our cities;
• conserve fuel and reduce exhaust emissions by combining necessary motor vehicle trips;
• turn off all lights and electrical appliances in unoccupied areas;
• use fans to circulate air. If air conditioning is necessary, set thermostats at 78 degrees;
• close the blinds and shades to limit heat build-up and to preserve cooled air;
• limit use of household appliances. If necessary, run the appliances at off-peak (after 7 p.m.) hours. These would include dishwashers, dryers, pool pumps and water heaters;
• set refrigerators and freezers at more efficient temperatures;
• purchase and install energy efficient lighting and appliances with the Energy Star label; and
• reduce or eliminate outdoor burning and attempt to minimize indoor sources of PM 2.5 such as smoking.

DEC and DOH issue Air Quality Health Advisories when DEC meteorologists predict levels of pollution, either ozone or fine particulate matter (PM2.5), are expected to exceed an Air Quality Index (AQI) value of 100. The AQI was created as an easy way to correlate levels of different pollutants to one scale, with a higher AQI value indicating a greater health concern.

Ozone is not a direct emission, and is produced indirectly when sunlight chemically reacts with nitrogen oxides (NOx) and volatile organic compounds (VOCs) from automobile exhaust and industrial emissions. High ozone is not as visible as PM2.5 because it is a colorless gas, but will produce hazy skies and reduce visibility in high concentrations.

Ozone levels generally decrease at night and can be minimized during daylight hours by curtailment of automobile travel and the use of public transportation where available.

Information on ozone and PM 2.5 is available on DOH's website.