THE decidedly good news about ridership of Baltimore's Central Light Rail Line means less congestion on heavily traveled thoroughfares of the region, but it may not necessarily mean less pollution.
Most passengers in the recent survey had switched from taking the bus. Many of those buses, with their internal combustion engines, are still operating on more or less the same schedules, emitting no fewer pollutants into the collective airshed.
A third of riders get to the station by auto, a third by bus. Thus, two-thirds of light-rail passengers use a motor vehicle, which contributes to the area's summer smog formation, before shifting to the cleaner, electric-powered train.
It gets worse. The heaviest amount of polluting hydrocarbons and carbon monoxide from motor fuel combustion are released within the first two miles of any trip, before the catalytic converter and other pollution-controls heat up.
So a third of light-rail riders are still generating a significant amount of air pollution from their autos even though they are counted as taking the clean-air alternative. The survey found 3.5 percent arrived at the station in a car pool, but didn't ask how many had switched from a car pool that continued on with fewer riders.
Some experts say alleviation of traffic congestion along key arteries through mass transit encourages other vehicles to return to those routes, especially trucks that are subject to commercial decisions about relative speed of movement.
This illustrates the dilemma and frustrations of trying to craft a local transportation system that can have a meaningful impact on cleaning up the region's polluted air.
Electric vehicles used as commuter cars to light-rail stations marelieve this air quality burden. Fleets of these nonpolluting vehicles could be available at major transit stations and quickly rented overnight by credit card or smart card. Since they return to the same station daily, repairs can be made efficiently.
Demonstrations of these "station cars" are planned for five U.S. locations this fall, with more than 100 cars put into service. Three small manufacturers, hoping to cash in on the California mandate for selling electric cars in 1998, are producing the test vehicles.
* * *
EXPERIMENTS in Artificial Intelligence (Spell-Checker as Political Pundit), Part II:
Last week a colleague reported in this space on an academic who had spell-checked in his computer a document containing the names "Schaefer" and "Schmoke." The word processor he was using, Microsoft Word, not finding either of those in its dictionary, offered these suggestions of what the writer might have intended: "schemer" and "schnook."
Well, every scientific experiment needs to be replicated. Another computer hacker tried it with WordPerfect. For Schaefer, it suggested we meant "scoffer" or "stuffier." For Schmoke, "schmoe."