There are signs that acid rain is already beginning to affect our lives, although in fact rain naturally has a weak acidity (an acid-base value of about 5.6) due to bonding with carbon dioxide in the atmosphere during precipitation.
由一些現象看來，酸雨已逐漸影響到我們的生活；不過，雨水在降落時與大氣中二氧化碳結合，本來就呈弱酸性（酸鹼值五．六左右）。