Theory question 308
Weather(a) With the aid of diagrams, explain how the following factors affect the temperature of a place: (i) latitude; (ii) aspect and slope.
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(i) Latitude: near the Equator the sun's rays are vertical, concentrated on a small area and pass through less atmosphere, so temperatures are high; towards the poles the rays are oblique, spread over a larger area and pass through more atmosphere, so temperatures are low; temperature therefore decreases from the Equator to the poles. Diagram: globe with vertical and slanting rays.
(ii) Aspect and slope: slopes facing the sun (south-facing in the Northern Hemisphere, north-facing in the Southern) receive direct rays and are warmer than slopes facing away; steep slopes facing the sun receive rays more directly than gentle ones; shaded slopes are cooler and may keep snow longer; this affects settlement and farming (e.g. vineyards on sunny slopes in the Alps). Diagram: valley with sunny (adret) and shady (ubac) slopes.
Draw a diagram for each factor.