In the 1970s, environmentalists feared global cooling. The dawn of a new Ice Age was said to be just around the corner, with human activity as the culprit. Why? Humans contributed to particulates that blocked the Sun’s radiation from reaching the Earth. That scare blew over, but a paper presented earlier this summer at the 19th International Conference on Nucleation and Atmospheric Aerosols suggests that the global cooling theory may have contained a kernel of truth:
Pollution controls have contributed to a more transparent atmosphere, thus allowing for “…a staggering increase in surface solar radiation of the order of ∼20% over the last decade.”
A new paper (O’Dowd et al.) from the National University of Ireland presented this summer at the 19th International Conference on Nucleation and Atmospheric Aerosols suggests that clean air laws put in place in the 1970′s and 80′s have resulted in an increase in sunlight impacting the surface of the Earth, and thus have increased surface temperatures as a result. In one fell swoop, this can explain why surface temperature dipped in the 1970′s, prompting fears of an ice age, followed by concerns of global warming as the air got cleaner after pollution laws and controls were put in place.
Surface radiation has increased sharply in the United States, Europe and Japan, where pollution controls have made the air much cleaner, but not in China and India, where industrial development has outpaced emissions reductions efforts:
There is much more at Watts Up With That. More work remains to be done, but it is a delightful thought, isn’t it? Who’s responsible for global warming? The EPA!