First Paragraph
It is difficult to imagine a natural system more complicated than the climate system. With its extraterrestrial forcing, as well as various terrestrial components in the atmosphere, the cryosphere, the biosphere, the solid Earth, the ocean, and countless feedbacks among them, the climate system almost defies description. Who among us could master all those subjects? Understanding, mitigating, and preparing for climate change is one of the great challenges facing humanity this century, but how can we present all the issues and uncertainties to the general public? One approach is to write an authoritative text directed at students at the undergraduate level.