Geography Reference
In-Depth Information
during the dry season. Much of California (save the mountains, deserts, and northern coast) experien-
ces this climate, which explains why wildfires are a common dry-season hazard in that state.
Various fruits prized fortheir sweetness and/orjuices (grapes in particular) dominate agricultural land
use. Lack of rain during summer, when the fruits ripen, deprives plants of moisture that would be
taken up by root systems and dilute the natural juices. This is a very big deal for the wine industry,
for which valuable vintages have everything to do with lack of rain while grapes mature. As to why
this kind of climate happens in the first place, predominant wind systems (associated with shifting
atmospheric pressure belts) blowing from the land to the sea during summer is the culprit.
Marine west coast
This climate is characterized by mild to cool summers and cool winters. Its name pretty much tells
you where you'll find it — on the west coast of continents in the middle to high-middle latitudes.
For virtually every occurrence, the principal determining factor is a warm ocean surface current im-
mediately offshore. Coastal mountain ranges prevent this climate from spreading inland and occupy-
ing large areas in North America, South America, and Australia. Conversely, lack of Atlantic coastal
mountains in much of Europe allows the marine atmosphere to uninterruptedly waft eastward and
characterize most of that region.
The natural vegetation of this climate is mixed coniferous (needle-leaf) and deciduous forests, the
two types respectively dominating in the higher and lower latitudes. Over the centuries humans have
deforested much of that portion of Europe where this climate is found and converted the land to ag-
ricultural use — the warm temperatures attendant to the warm currents serving as a boon for agricul-
ture. The same is generally true of the marine west coast areas of Australia, New Zealand, and South
Africa.
In North America, relatively little conversion of forests to farms occurred in areas of marine west
coast climate because of the prevalence of mountainous terrain. As a result, the natural vegetation
serves asthe preferred crop—which istosaythat forestry isamajor endeavor.Andwhat forests they
are! The relatively high temperatures and abundant precipitation wrought by the warm-water current
offshore created lush and majestic stands, including the redwoods of Northern California. As demand
for timber — much of it emanating from Asian markets — has grown, so has controversy between
loggers and environmentalists regarding the extent and nature of cutting. The future of the relatively
few remaining “old-growth forests” is a particularly contentious flash point.
Cooling Off: Humid Microthermal Climates
