Meanwhile the carbon dioxide content of the oceans will have
doubled. This raises an incidental question about the welfare of
sea organisms. We know that an increase in carbon dioxide
concentration increases the acidity of water, and that many
marine animals are extremely sensitive to changes in acidity.
However, if the carbon dioxide content of the air were to
increase sevenfold, the acidity (pH) of sea water would not rise
more than .5 above its present value. Thus changes in carbon
dioxide concentration, which have such a profound effect on
climate, will probably not disturb future marine life. Perhaps
only man will be uncomfortable. We shall be able to test the
carbon dioxide theory against other theories of climatic change
quite conclusively during the next half-century. Since we now
can measure the sun's energy output independent of the
distorting influence of the atmosphere, we shall see whether the
earth's temperature trend correlates with measured fluctuations
in solar radiation. If volcanic dust is