Kerry H. Cook

"The (AEJ, also known as the West African jet) is a prominent feature of the complicated structure that forms over in summer. ... The jet may be instrumental in creating an environment in which African wave disturbances develop through and instability (e.g., Rennick 1976; Thorncroft and Hoskins 1994a,b) and may play a role in determining the region’s precipitation distribution through these wave disturbances (e.g., Payne and McGarry 1977; Rowell and Milford 1993) or through its role in determining the large-scale column moisture convergence (Rowell et al. 1992). In addition, the African wave disturbances have long been identified as sources of activity in the Atlantic (e.g., Frank 1970). A better understanding of why the jet forms, and its sensitivity to surface conditions, will be useful for understanding the mechanics of the region’s basic climate dynamics as well as its intra- and interannual variability; such an understanding is necessary to advance our prediction capabilities."

"In the absence of regulation and/or some prohibitive cost attached to the release of es into the , will freedom in the climate commons bring ruin to all? Or will a more complex scenario develop, in which unequal use of the climate commons brings benefit to some and ruin to others?"

"The lies above the , extending to about 48 or 1 , and is capped by the . It is a vertically stable, stratified region—hence its name—in which increases with altitude. The ("middle sphere") stretches from the stratopause to about 80 km, with temperatures again decreasing with height. The region of transition to interplanetary space, about 80 km, is the . ... The only region where the incoming is strongly absorbed is in the stratosphere, where absorbs wavelengths. The stratopause marks the level of maximum absorption of solar radiation by ozone, but it is not the location of the greatest ozone concentration. Ozone concentrations generally peak near about 25 km elevation, but much of the ultraviolet radiation has been removed from the incoming solar beam at that level by the ozone above."

"The West African monsoon season begins in late April or early May with the onset of spring rains along the n coast near 4°N. The precipitation maximum remains over the coast until late June or early July. At that time, the rainfall maximum shifts into the southern , near 12°N, often over the course of a few days. This shift in the latitude of the rainfall maximum is known as the West African monsoon jump."