"If civilization came to an abrupt halt, how much would the global temperature change? Would it spike 0.5 or even 4 degrees Celsius as some claim, or could it even drop? This is a a very tough question. Aerosols in the atmosphere are of many flavours. The sulphur type reflect sunlight causing surface cooling, while the black carbon type absorb sunlight causing net warming. Both types change cloud properties; both have great spatial variability. I examine these factors in great detail." Dr. Paul Beckwith
