THE TECHNOLOGICAL ALTERNATIVE

If it is so troublesome to prevent air pollution in L.A., how about cleaning the air after useful activity has polluted it? It's done with bodies, teeth, dishes, cars and carpets; why not with the air?

First some meteorological basics. Any urban basin is bad for air quality, because atmospheric circulation (ventilation) is sealed off from several sides, and is stopped almost completely when the lid is put on from the top by a temperature inversion (a layer of warmer above colder air), because the polluted air no longer rises from the surface as it does for a normal temperature profile. The additional trouble with Los Angeles is that it only gets 13.5 inches of rain per year, and it takes 0.5 inches to clear the air under the inversion layer, which is present at 2,000 ft altitude most of the time. The result is that the concentration of pollutants rises to about 13 times their daily production until rain clears the air again.

Next, consider coastal winds. Ground has a smaller thermal inertia than the sea: it gets hot during the day and cools during the night, whereas the sea has a pretty constant temperature over a diurnal cycle. Since winds blow from denser to rarer, i.e., from cooler to warmer air, there is a breeze from the cooler sea to the warmer land during the day; but during the night, when the ground becomes cooler than the sea, the direction is reversed as cool land air replaces the air rising above a warmer sea.

So if L.A. cannot bring rain to the atmosphere, how about taking the atmosphere into the rain? As just explained, it sloshes back and forth between land and sea without human help; all you have to do is put up a big water curtain near the coast to scrub it as it passes through it by its own accord.

Any side effects and environmental impact? Yes: since some of the wave energy is extracted, the waves will pound less strongly against the coast, reducing erosion by an estimated 60%.

The coastal air wash, by the scientists' calculations, would reduce air pollution in the L.A. basin by 53% in the summer, and by 79% in the winter. (A smaller fraction of the air is moved out from the basin during the summer.) The cost, amortization and maintenance, is estimated at $87/year, compared with $795 for the quixotic regimentation by the Air Quality Soviet.

The jets would, of course, first have to be tested in a demonstra-tion project, and a number of impacts would have to be inves-tigated. But the AQ Soviet said no. Like all politicians, they use environmentalism as a cloak behind which to stifle technology, instead of developing technology to protect the environment.

[Source: Summary and lecture slides The Coastal Air Wash System, by Citizens for a Clean California, scientific research by Hughes Aircraft Co. Sup- port Systems, Box 9399, Long Beach, CA 90810, tel. 213-513-3915.]