Forming the climate of North America
Since North America is very elongated from north to south, there are great differences in the temperature characteristics of its northern and southern parts. This is due to the increase in the angle of incidence of the sun’s rays on the earth’s surface. So, in the north even in July the average temperatures do not exceed 0 … + 8 ° C, and in the south the average annual temperatures are above +20 ° C.
Most of the continent is dominated by the Western transport – constant winds of temperate latitudes, carrying the moisture-saturated air from the Pacific Ocean. The southern part of the continent is subject to the influence of the North-East trade wind from the Atlantic Ocean. North-eastern winds penetrating from the north all year round bring cold and dry air from the Arctic. In the east of the mainland, weak seasonal winds form monsoons on the border of land and ocean. In the summer they blow from the Atlantic Ocean and bring cool and humid weather, in
Significantly affects the climate of the continent relief. The flat surface of the central part of North America promotes free movement over the territory of various air masses. In the winter, cold arctic air easily penetrates far to the south, and tropical hot air – to the north. In the summer, the land is warmed up, and the effect of cold air is weakened. The large difference in temperatures and pressures between cold and warm air masses contributes to the formation of hurricanes and tornadoes. In America they are called a tornado. They move along the usual routes for themselves – between the Cordilleras and the Appalachians. This territory is called the “tornado alley”. The winds in the tornado reach a hurricane speed of up to 800 km / h. They roar like hundreds of jet planes. Tornadoes easily tear out the roots of trees, rearrange railroad cars, objects trapped by a tornado and rotating at a frenzied speed, pierce the concrete walls of houses. Inside the vortex, the pressure is very low, so houses that
Mountains act as barriers to the movement of air masses. The Cordillera Wall delays a significant part of the moist air masses coming from the Pacific Ocean. The mountain masses that passed through the mountains contain less moisture. Therefore, if on the western slopes of the Cordillera falls more than 3000 mm of precipitation, then in the flat east only up to 500 mm. In the east, the Appalachians hinder the advance into the continent of the monsoon. Significant influence on the climate of the coast of the sea currents. Thus, the cold California current conditions hot and dry weather on the southwestern coast of the continent. Warm currents – the Alaskan in the northwest and the Gulf Stream in the east, on the contrary, contribute to the arrival of humid air masses on the continent.