The flaw in the UN reasoning is clear, however. The alarmists claim the global warming since 1976 has been too rapid to be caused by natural forces, and therefore must be man-made. However, the earth's Industrial Revolution went global after 1945 releasing the first big flush of CO2 emissions. That burst of greenhouse gases should have sharply boosted the earths temperatures. Instead, the earth's temperature declined from 1940-75.