“Even more concerning is that massively harmful global environmental changes have managed to elude detection for decades, even when they should have been obvious all along. Two classic examples are ocean acidification (Figure 43) and plastic pollution. You probably know that dissolving carbon dioxide in water makes it more acidic. Yet this simple chemistry was not widely considered a problem for oceans until 2003 when global ecologist Ken Caldeira did the maths that recognized the scale of the threat. Already, the growth of some corals is slowing. If CO2 emissions continue unabated, Earth’s coral reefs and many species of shellfish will disappear by the end of this century, based on comparisons with prior intervals of Earth history with more acidic oceans. Worse still, warmer oceans might do the job first. Yet even in Planet Under Pressure, the most comprehensive summary of Earth system science ever, published in 2004, there was no mention of ocean acidification.”