We know the vast amount of coal burned by China to produce manufactured goods (that could have been produced user cleaner energy if not for Kyoto) produces huge amounts of carbon soot that can change the albedo. (judithcurry.com)
Fouling occurs when lube oil emissions coat the catalyst with carbon soot. (ecooptimized.com)
I should add that I'm all for reducing carbon soot, but in the zealous rush for solutions, sometimes too many cooks spoil the soup. (wattsupwiththat.com)