陡峭的纽约交易ffic toll would reduce gridlock, pollution

"If we charge a high dollar amount of tolls, we can decrease the number of cars and taxis, shrink gridlock, bring down carbon dioxide emissions and reduce particulate matter," said Oliver Gao, professor of engineering and director of Cornell's Center for Transportation, Environment and Community Health. "This is good news for the environment and from a public health perspective."

About 1 million tons of greenhouse gas emissions -- mostly carbon dioxide -- come from automobile and truck traffic in lower Manhattan annually. In modeling different scenarios using air quality processing software, the researchers determined exhaust emission reductions based on the tolls charged to enter the central business district of Manhattan. A toll of $5, they found, would result in a reduction of 72,648 tons of greenhouse gas emissions annually. For a $10 toll, the reduction would be 119,097 tons, and a $15 toll would yield a 157,747-ton drop.

A $20 toll would eliminate 40% of midtown traffic and reduce greenhouse gas emissions by 182,065 tons per year.

Entrance tolls will also drop the volume of particulate -- soot and other tiny particles measuring less than 2.5 micrometers that are linked to poor health and give Manhattan a hanging haze, according to the paper.