(a) Highlight any three effects of either rotation or revolution of the earth (b) Give reasons why: (i) all areas north of the Arctic Circle have twenty fou...

Answer Details

(a) Three effects of the rotation of the earth include:

(i) It causes the alternation of day and night.

(ii) It causes the deflection of winds and ocean currents (Coriolis effect).

(iii) It causes differences in local time from place to place.

(b)(i) Reasons why all areas north of the Arctic Circle have 24 hours of daylight on June 21:

(i) On June 21, the North Pole is tilted towards the sun.

(ii) The overhead sun is at the Tropic of Cancer.

(iii) The circle of illumination extends beyond the North Pole, leaving all places north of the Arctic Circle within the illuminated half of the earth.

(iv) As the earth rotates, the sun does not set in these areas; hence, they experience continuous daylight.

(b)(ii) Reasons why areas within the tropics have more sunshine than areas outside the tropics:

(i) The sun is overhead or nearly overhead within the tropics at some time during the year.

(ii) The sun’s rays strike the tropics more directly and are concentrated over a smaller area.

(iii) Areas within the tropics have fairly equal lengths of day and night throughout the year, giving relatively long periods of daylight.

(iv) Outside the tropics, the sun’s rays are more slanting, spread over a wider area and pass through more atmosphere; therefore, they receive less intense sunshine.