View article

This chapter provides a statistical description of the atmospheric general circulation, including its mean state and large-scale variability. Evidence for the poleward energy and momentum transports by the atmosphere is laid out, and the mechanisms behind these transports are explored. The mean meridional and eddy components of the atmospheric circulation are described, and their relative influences on energy and momentum transport quantified using reanalysis data. The chapter closes with a synthesis summary of major sources and sinks of energy and angular momentum and their roles in driving the atmospheric general circulation. The material in this chapter is by necessity incomplete. We will return to some aspects of the atmospheric general circulation (such as the tropical Walker circulation and the monsoons) in later chapters, but there are many aspects of the atmospheric general circulation that remain beyond the scope of this course. A number of useful resources are available for readers seeking additional details and/or alternative presentations of this material (eg, Gill, 1982; Holton,