Higher cumulative concentrations of ozone in rural areas had handicapped the rural trees, she concluded.
The data measures ground-level concentrations of ozone, a chemical that forms smog.
But a new experiment has shown that fairly common concentrations of ozone, the eye-stinging ingredient in smog, can sharply impede this process.
The standard, stated in terms of average concentrations of ozone at ground level over an eight-hour period, is now 84 parts per billion.
In general, Dr. Gregg writes, rural areas in New York, New Jersey and Connecticut have higher concentrations of ozone near the ground than cities do.
Known concentrations of ozone around the ambient ground level were generated by a calibrated ozone generator.
The scientists say air monitoring conducted over central Pennsylvania on Aug. 15, the second day of the blackout, showed sharply reduced concentrations of ozone and sulfur dioxide, which contribute to haze and smog.
Greater concentrations of ozone are more damaging than was thought: the new report reckons high ozone levels cause an 8-15% reduction in yields compared with normal crops.
Average climatological boundary concentrations of ozone and precursors were taken from Laboratoire de Météorologie Dynamique- INteraction with Chemistry and Aerosols (LMDz-INCA) global simulations25 for the specific periods and scenarios.
The experiments were carried out at various constant reaction temperatures (T), space velocities (SV) and inlet concentrations of ozone (CO3,in).
One focus is on chemical mechanisms that control concentrations of ozone (O3) and secondary organic aerosol (SOA), secondary pollutants with profound effects on climate, human health, and the environment.
