Geography Reference
In-Depth Information
systems dumps on Bergen, and the 46 inches of precipitation that Charleston, SC, receives by being
located near the Gulf Stream directly across the Atlantic.
Coastal deserts
Casablanca, Morocco, highlights one of the world's most provocative geographic juxta-
positions: places where oceans border deserts. Indeed, a couple of coastal deserts exist.
What most have in common is a neighboring cold water current that makes evaporation
difficult and rainfall unlikely.
Going against the norm: El Niño and La Niña
You should remember that climate is an average of yearly conditions, but that in any given year very
“un-average-like”eventscanoccur.ElNiñoandLaNiña,whichhappeneverysomanyyears,provide
good examples. (Niño and niña mean boy and girl in Spanish.) As you can see in Figure 9-8, during
an El Niño, the surface waters become unusually warm in the tropical portion ofthe Pacific. The reas-
ons for this are not fully understood; but because the conditions occur around Christmas in the waters
off western South America, the local populace call it El Niño, referring to the Christ child. During La
Niña, the opposite happens (“girl” being the opposite of “boy”) — the water is unusually cold.
Because the affected ocean water circulates, and also influences the behavior of atmospheric pressure
belts (which you can read about in the next section), the impact can be substantial and widespread.
Just what that means varies from place to place and year to year. Sometimes, for example, rainy sea-
sons become extremely stormy and dry seasons become prolonged droughts. On the other hand, the
effects are not always bad, as may be evidenced perhaps by a normally harsh winter that turns up
mild. Generally, the media have cast “the boy” and “the girl” as climatological brats. In some times
and places, however, they are the most pleasant kids you'd ever want to have around.
