Temperature

TEMPERATURE

This can be defined as the degree of hotness or coldness of a place. The instrument that is recognized in measuring a temperature is thermometer. Temperature varies from place to place and depends on various factors: (i) Latitude (ii) Altitude (iii) Cloud cover and humidity (iv) Length of days and ocean current (v) Distance from the sea (vi) Prevailing winds.

1. LATITUDE: Due to the earth inclination, the mid-day sun is almost overhead within the tropics but the sun rays reach the earth at angle outside the tropics. Temperature diminishes.
2. ALTITUDE: Since the atmosphere is mainly heated by condition from the earth, it can be expected that places nearer to the earth’s surface are warmer than those higher up. Thus, temperature decreases with increasing height above sea – level.

The rate of decrease with altitude (lapserate) is never constant, ranging from place to place and from season to season.

3. CONTINENTALITY: Land surface area heated more quickly than water surface because of the higher specific heat of water. In other words, it requires only one third as much energy to raise the temperature of a given volume of land by 0.6⁰c (1⁰F) as it does for an equal volume of water.

The accents for the warmer summers, colder winters are greater range of temperature of continental inferiors as compared with maritime districts.

4. OCEAN CURRENTS AND WINDS: Both ocean current and winds affects temperature by transporting their heat or coldness into adjacent regions. Ocean currents like the gulf stream or the Atlantic ocean warm the coastal districts of western Europe, keeping their parts ice – free. Ports located in the same latitude but washed by cold currents such as the cold landed or current off north east Canada are frozen for several months.

Cold currents also tower the summer temperature, particularly when they are carried land ward by onshore winds. Onshore western lies convey much tropical warm air to temperature coasts, especially in winters. The westerlies that come to Britain and Noruay tend to be cool winds in summer and warm winds in winter and are most valuable in moderating the climate.

Local winds e.g. Fohn, Chinook, Sirocco, Mist produces marked changes in temperature.

5. SLOPE SHELTER AND ASPECT: A steep slope experiences more rapid change