Climates of North America

thank you on any one January day in North America it is both warm and cold on the same day it is also very wet and very dry North America has a wide variety of climates each of these regions has its own kind of climate one area is usually cold most of the time while another is nearly always warm one region is usually mild and wet while another is mostly hot and dry this pattern of climates in North America is partly controlled by great masses of very cold air in the North in the winter this air sweeps Southward and brings freezing temperatures and snow climate is also partly controlled by great air masses far to the South as this warm tropical air advances northward it brings summer warmth to much of the continent it also brings rain especially in the east air usually stays far to the North in summer but blankets most of the land in winter when the cold air Retreats again it continues to keep one Northern area near freezing even in summer in Winter although the cold air affects most of the continent it does not reach the southern tip of Florida which remained warm all winter it is almost as warm here in mid-January as it is in July frosts are very rare some are never really ends and Farms can produce crops all year round tropical plants and animals also flourish in this warm wet climate the tip of Florida has a tropical climate thousands of miles to the north is a region of Perpetual ice and snow winter never ends on the mild thick Greenland ice cap during the long Arctic night the ice cap and the frozen Arctic Ocean act as a refrigerator cooling much of the continent the Greenland ice cap is said to have an ice-capped climate and is virtually lifeless this region is not permanently covered by ice and snow and there is life here as the long Arctic night slowly ends some of the sea ice melts and summer activities begin for a short time each year the ice and snow disappear on this Great Arctic plain or Tundra and the surface of the Earth thaws just deeply enough to allow very small Hardy plants to grow the Arctic tundra is said to have a tundra climate here the summers are only slightly longer but this region has a very different appearance on the southern edge of the treeless arctic tundra one comes to the tree line it marks the limit of the great evergreen forest that covers much of North America will come here for wood or minerals or to hunt and fish they raise few crops even where cultivation is possible because summers are usually cool and very short followed by long bitterly cold Winters this forested region has a sub-arctic climate to the South is an area where the climate is not so severe longer summers with plenty of rain are ideal for growing corn the most important single crop in North America the corn provides abundant fodder for beef and dairy cattle and other livestock that help to feed the many great cities which have sprung up in the region although summer is often hot and sticky it is quickly followed by cold air and snow that sweeps rapidly over the continent and remains for over a third of the year in parts of this region this area has a humid continental climate the northern part has shorter Summers and colder Winters the southern section has longer summers and milder Winters to the South is a region with a climate more like that of tropical Florida cotton needs about six months of warmth and plenty of moisture to brighten and it grows well here in the long hot summers the air is usually very humid and there is much rain and even during the short winter clouds bring rain much more often than snow this region has a subtropical climate now this north to south pattern of climate is complete in the far north there is a region that has no warm period the further south the region is the longer and warmer are at Summers most of these regions get an adequate supply of moisture all these climates are determined mainly by differences in temperature but the climates of the West are determined mainly by rainfall or the lack of it for instance this whole region is usually very dry because the winds that bring rain to the east usually do not reach it and the winds from the Pacific lose most of their moisture at the Western mountains dryness is far more important than temperature in determining conditions here it is too dry for trees to grow on these vast grasslands which are sometimes called steps cattle Grays where the land is hilly or too dry to cultivate and hard wheat for making bread is an important crop on the Prairies where there is a little more moisture this grasslands region is said to have a step climate on the west coast also it is mainly the amount of moisture that controls climate in summer there is some rain along the coast but in Winter the winds move South and bring heavy rainfall to one area less to another further south there is little or no rain at all this region receives the most rainfall in North America thank you Evergreens like the Douglas fir Grill to immense size in this very wet and Mild Pacific climate in Winter the mild Pacific winds bring a great many dull rainy days to the coastal valleys there is Little Frost or snow the coastal area with the heavy rainfall has a marine climate this Coastal area receives almost no rain at all although the land is warm and on the edge of the ocean the winds are dry and bring no rain from the sea and for many miles along the coast of lower California there is Barren white sand in this desert climate There is almost no life by drilling Wells and building irrigation canals from distant Rivers man can change the desert and grow many useful crops between the very wet and very dry regions is the area that gets a little rain each year oranges lemons figs and other crops are grown in the irrigated Orchards of Southern California this region has the very warm dry Summers and Mild Winters with little rain that are typical of many Mediterranean lands and this dry warm climate has attracted millions of people to this small area Winters are so mild that on New Year's Day the famous Rose Bowl game is usually played in pleasantly warm weather swarm region with its winter rainfall isn't the land surrounded by mountains is shut off from almost all rain only very Hardy domestic animals like sheep and goats can survive where water is so scarce many plants are adapted to life in severe desert conditions and so are some animals from the desert one can see mountains that have captured some moisture from the air part way up the mountains there may be forests and on the cold Peaks tundra-like vegetation grows the melting snow provides moisture the year round for many birds and animals there is no one mountain climate there are many different climates which change according to altitude much of the Arid land between the mountains has a desert climate the Western climates differ mainly in the amount of rainfall they receive the Marine climate gets abundant rainfall while the desert climate gets almost done in the west wet and dry are the two extremes that most affect climate the extremes elsewhere in North America are hot and cold on the Greenland ice cap it is always cold and in tropical Florida it is almost always born North America also has many climates between the extremes of hot and cold wet and dry in fact there are examples here of most of the climates found throughout the world [Music]