Climate of Pakistan

Climate of Pakistan

As Pakistan is located on a great landmass north of the tropic of Cancer (between latitudes 24° and 37° N), it has a continental type of climate characterized by extreme variations of temperature, both seasonally and daily. Very high altitudes modify the climate in the cold, snow-covered northern mountains; temperatures on the Balochistan Plateau are somewhat higher. Along the coastal strip, the climate is modified by sea breezes. In the rest of the country, temperatures reach great heights in the summer; the mean temperature during June is 100° F (38° C) in the plains, where the highest temperatures can exceed 117° F (47° C). In the summer, hot winds called loo blow across the plains during the day. Trees shed their leaves to avoid loss of moisture. The dry, hot weather is broken occasionally by dust storms and thunderstorms that temporarily lower the temperature. Evenings are cool; the diurnal variation in temperature may be as much as 20° to 30° F (11° to 17° C). Winters are cold, with minimum mean temperatures of about 40° F (4° C) in January.

The controlling factors of the climate are:

1. The sub-Tropical location of Pakistan that tends to keep the temperature high, particularly in summer.

2. The oceanic influence of the Arabian Sea that keeps down the temperature contrast between summer and winter at the coast.

3. Higher altitudes in the west and north that keep the temperature down throughout the year.

4. The Monsoon winds that bring rainfall in summer.

5. The Western Depression originating from the Mediterranean region and entering Pakistan from the west that brings rainfall in winter. These cyclones make a long land journey and are thus robbed of most of the moisture by the time they reach Pakistan.

6. A temperature inversion layer at a low elevation of about 1,500 m in the south during the summer that does not allow the moisture-laden air to rise and condensation to take place.

Temperature regions of Pakistan

Pakistan can be divided into four broad temperature regions:

1. Hot summer and mild winter: 32o C or more in summer and 10 to 21o C in winter.

2. Warm summer and mild winter: 21 - 32oC in summer and 10 to 21oC in winter.

3. Warm summer and cool winter: 21 - 32oC in summer and 0 - 10oC in winter.

4. Mild summer and cool/cold winter: Summer temperature between 10 and 21oC and winter temperature between 0 and 10oC.