Google "Global Dimming". The world is getting dimmer - in some areas 22% dimmer than in 1950. This is what is counteracting global warming. Google "Global Dimming 9/11". Following up on a theory, it was shown that in the 3 days of no flights over the USA following 9/11, the effect of not having contrails reduced global dimming by 1%. In other words, flying is part of the solution to global warming - the condensation trails reflect sunlight back into space. The reason the dire predictions of "An inconvenient truth" haven't occurred is that global dimming has counteracted the effects of global warming. So we should be flying more.