Although it looks like ordinary rain, acid rain can destroy buildings, kill trees, and render lakes and rivers lifeless. In What Causes Acid Rain?, Isaac Asimov explains how acid rain forms and how it can be prevented.

For general information on the “Ask Isaac Asimov” series, see What Is a Shooting Star?

On the whole, the environmental books in the “Ask Isaac Asimov” series fare better with me than the astronomical books; perhaps this is because Asimov doesn’t cover environmental issues elsewhere for young children except in the relatively obscure Earth: Our Crowded Spaceship. As a result, I’m a bit less resentful of the incredible cost of this particular book and actually enjoyed it. I would definitely recommend it to an elementary school student with an interest in the subject.

I did, nonetheless, find it a bit disappointing in its relatively vague description of how the rain actually becomes acidic in the first place. The point that plants and animals have adapted to the normal, very slight acidity of rain but not the higher level induced by human activity also went right past my two children when they read the book. The end result is that they had about as many questions at the book’s end as at its beginning.

This is slightly offset by the fact we’ve got a marvelous picture of the Parthenon being eaten alive by—well, by Athenian air pollution, actually, and not acid rain, but let that pass. That, however, is a virtue of the illustrations and is nowhere explicitly called out in the text (although Asimov does point out that acid rain eats away at ancient buildings).