Temperature

The degree or intensity of heat present in the atmosphere near the earth’s surface is measured in temperature. The molecular movement of particles composed of a substance is represented by heat, and the temperature is measured in terms of the degrees of hot (or cold) of a thing (or a place). 

Factors Controlling Temperature Distribution

The temperature of the air in any region depends on:

The latitude of the place:

1. The temperature of any place depends on the insolation received.
2. The temperature differs from place to place as the insolation varies according to the latitude.

The altitude of the place:

1. The terrestrial radiation heats the atmosphere directly from below. As a result, high temperatures are recorded near sea level. The Places situated at higher elevations have comparatively low temperatures because the temperature falls at heights.
2. Average Lapse Rate: The rate of temperature decrease with height is known as the Average Lapse Rate.

Distance from the sea:

1. Variation overseas is less: The sea absorbs heat slowly in comparison to land. The land is quick in the process of heating up and cooling down.
2. The lands closer to the sea can be somewhat influenced by the land and sea breezes, and it helps moderate the overall temperature.

Air-mass and Oceanic Currents:

1. The temperature is also affected by the passage of air masses like the sea breezes and land breezes.
2. The places usually experience a high temperature on the impact of warm air masses, and the places that are impacted by the cold air masses experience low temperature.
3. The places located on the coast experience the warm ocean currents flowing. As a result, these places record higher temperatures than the regions located on the coast where the cold currents flow.

Local aspects:

The local aspects also affect the temperature. For example, Due to the construction of buildings, the area experiences more temperature also called the Heat Island effect.

Distribution of Temperature:

The months of January and July are important to understand global temperature distribution.

1. The latitude can have a significant impact on the temperature since the isotherms usually are parallel to the latitude.
2. This kind of deviation has more effect in January when compared to July, and this is particularly true in the northern hemisphere.
3. The land surface area is larger in the northern hemisphere in comparison to the land surface of the southern hemisphere. So, the effects of ocean currents and landmasses are well defined.
4. The existence of warm ocean currents, North Atlantic drift, and Gulf Stream make the Northern Atlantic Ocean warmer, and due to this, the isotherms stoop towards the north.
5. The effect of the ocean is well pronounced in the southern hemisphere.
6. The isotherms are more or less parallel to the latitudes, and the temperature variation is more gradual than in the northern hemisphere.
7. The isotherms generally run parallel to the latitude during July.
8. A warmer temperature of more than 27 degrees celsius is recorded in the equatorial oceans.
9. More than 60°C is recorded as the maximum temperature range over the north-eastern part of the Eurasian continent due to continentality.
10. The least temperature range, 3°C, is recorded between 20°S and 15°N.

Inversion of Temperature:

1. Usually, the increase in elevation can cause a decrease in temperature, and this phenomenon is called the average lapse rate. Sometimes, the reverse happens, which results in an inverted average lapse rate. It is termed the inversion of temperature. inversion and exists for a short duration.
2. Ideal situation for inversion: The day’s heat begins radiating off as we approach the night. By dawn, the earth will become much cooler compared to the air above. Near polar regions, temperature inversion stays throughout the year.                                                    Effects of the inversion:                                                                                                                                                                                     1. The stability in the lower layers of the atmosphere is promoted by surface inversion.                                                                               2. Dust and stone particles are found beneath the inversion layer. They fill the lower strata of the atmosphere as they are spread horizontally.
3. During the winter season, dense fog in the mornings is common.

• In Hilly or Mountain areas:

1. Air drainage is somewhat responsible for the inversion.
2. At night, cold air produced in the hills and mountains flows downwards under the influence of gravity.
3. The cold air is dense and heavy, and it acts similar to water. It moves down the slope to pile up deep inside in pockets and valley bottoms along with warm air above. This is known as air drainage. It protects plants from ice damage.