"Let me be perfectly clear about this" - Global Warming Part 4

At nature.com today:

Reductions in industrial emissions in many countries, along with the use of particulate filters for car exhausts and smoke stacks, seem to have reduced the amount of dirt in the atmosphere and made the sky more transparent.

That sounds like very good news. But the researchers say that more solar energy arriving on the ground will also make the surface warmer, and this may add to the problems of global warming. More sunlight will also have knock-on effects on cloud cover, winds, rainfall and air temperature that are difficult to predict.

At Friends of Science:

Myth 4: CO2 is the most common greenhouse gas.

Fact: Water vapour or clouds, which makes up on average about 3 % of the atmosphere, is the major greenhouse gas. CO2 makes up only about 3% of the greenhouse gases, or about 0.03% of the atmosphere. Moreover, because of its molecular weight and absorptive capacity, water vapour is 3000 times more effective than CO2 as a greenhouse gas. Those attributing climate change to CO2 rarely mention this important fact.