Airflows create not just towers and hills , but also some breaches and abysses .
气流不仅仅创造了云塔和斜坡，同样导致了缺口。
And the alternatives carry their own costs , whether in the form of considerable government subsidies for solar and wind ( neither of which provides consistent power due to natural variations in sunlight and airflows ) or in the form of greenhouse-gas emissions from fossil fuels .
