I have not been able to sustain much interest in the subject of global warmiong once I started thinking about it logically.
So here are some contradictory articles on the subject. …
Originally posted by The Register:
New research from NASA suggests that the Arctic warming trend seen in recent decades has indeed resulted from human activities: but not, as is widely assumed at present, those leading to carbon dioxide emissions.
Rather, Arctic warming has been caused in large part by laws introduced to improve air quality and fight acid rain.
Dr Drew Shindell of NASA's Goddard Institute of Space Studies has led a new study which indicates that much of the general upward trend in temperatures since the 1970s – particularly in the Arctic – may have resulted from changes in levels of solid "aerosol" particles in the atmosphere, rather than elevated CO2.
Arctic temperatures are of particular concern to those worried about the effects of global warming, as a melting of the ice cap could lead to disastrous rises in sea level – of a sort which might burst the Thames Barrier and flood London, for instance.
After so many people died in London's worst known smog in 1952, Britain introduced The Clean Air Act.
Power stations had to build air filters into their chimneys and send the vented smoke higher up into the atmosphere.
Central heating was introduced into cities so that the power production could take place to windward, outside the town centre locations inspired by Victorian gas-works.
The result was that in winter during anticyclonic weather the fall-out tended to travel hundreds of miles.
Once central heating began to become popular in itself (no longer a requirement but a desired home improvement) the smoke stacks became taller and more efficient.
(After the collapse of several cooling towers in the 1960's it was understood that the outside of these buildings also needed streamlining.)
Whilst this might point to a change in the climates of some areas, the locations involved initially are small, though the output large and the changes to places where the pollution falls are much much larger and probably quite capable of benefiting from carbon dioxide input and small amounts of metallic trace elements.
A lot would depend on the types of fuels used. Dirty coal and sulphur rich oil would produce or tend to produce dangerous fall-out if not properly controlled. And governments have an history of covering up dangerous mistakes.