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Latitude:
This is of prime importance in determining solar energy receipt. The earth sun relationship show that both the angle of the sun in the sky and length of day determine solar energy receipts. These two factors are determined by latitude. More insulation reaches the earth’s surface when the angle of the sun’s rays is 900 than when it is less than 900. The sun’s rays pass through a greater thickness of atmosphere to reach the higher latitudes than to reach the lower latitudes. The highest temperatures on earth are not found at the equator but near the tropic of cancer and Capricorn. This occurrence is explained by the apparent migration of the sun between 23.50 N and S. In its passage, the sun seems to move relatively quickly over the equator, but slows down as it progresses north and south. Thus between 60 N, and 60 S, the sun’s rays are vertical for 30 days, during the time of the equinoxes. Between 17.50 and 23.50 and S, the vertical rays occur for 86 days near the solstice. The longer period of the high sun and the concurrent longer days allow time for surface heat accumulation and thus give rise to the zone of maximum heating near the tropics. The heating is further enhanced by the clear skies near the tropics compared to the very cloudy equatorial belt.
Temperature regimes, especially the seasonal cycles, are also related to earth’s sun motions. The temperature regime at equatorial stations shows few variations, with two maximums at the period of equinoxes. Stations further north show a distant summer winter maximum and minimum, with the range generally increasing with latitude.
Surface properties:
The solar energy received on the earth surface depends on the type of surface the energy is striking. Of particular note is the surface reflectivity or albedo. Surfaces with high albedo absorb less incident radiation, with the result that the total energy available is diminished. Thus the polar ice caps are maintained because as much as 80% of the solar radiation falling on them is reflected.
Aspect and Topography:
The combined influences of steepness and direction faced by a slope determine its aspect. The importance of aspect is best seen in differences that occur on north-facing and south- facing slopes in the northern hemisphere. A north-facing slope may still have snow lying on it while a south-facing slope is quite clear. The north-facing slope gets less intense radiation and, as the sun gets lower in the sky, it will be in shadow long before the south-facing slope. The influence of aspect is seen in many ways; for example, the height of the level of permanent snow and ice on mountains will vary from one slope to another, while vegetation levels (e.g. the tree line) will also be affected. Similarly the depth of snow and frost are found to differ on north-facing and south facing slopes. Topography also plays an important role in the nature of climates of neighboring lowlands. On a continental scale, mountain ranges that run north-south have a different effect from those that run east- west. Thus the lack of any extensive east-west barrier in
the United States permits polar and tropical air to penetrate great distances into the continent. One result of this unobstructed flow of air is the high incidences of tornadoes in the United States. The relief alignment of continents also affects the flow of air masses into the interior.
francis1897 answered the question on October 4, 2022 at 13:40