Under a Black Cloud

The defining challenge of the twenty-first century for the entire world may very well be the health of our atmosphere, both the delicate balance of gases in its upper reaches and the air we breathe at ground level. Increases in carbon dioxide and other greenhouse gases appear to be resulting in rapid and possibly catastrophic global warming and climate change. Pollution at lower altitudes, which is caused by such things as car exhaust and industrial emissions, is causing the destruction of ...