Short essay on Low-Latitude Steppe Climate (BSh)

Low-latitude steppe climate occupies the transition belt between the hot deserts and the humid climates. On their equator-ward margins, the steppe climates are flanked by tropical humid climate, whereas on their pole-ward margins they make contact with either the mesothermal C, or the micro-thermal D climates.

Because these climates are found on the margins of the sub-tropical anticyclones and the trades, the shifting of the pressure system and wind belts with the change of seasons, makes the steppe regions experience rain producing winds and storms during a part of the year.

However, the precipitation is scanty and more irregular. It is on account of this short period of seasonal rains that the steppe climates are semi-arid in which the total amount of precipitation received is just more than one-half the potential evaporation.

Location:

Low-latitude steppe climates are found both north and south of the tropical hot desert of Sahara in Africa. The steppe climate to the north of Sahara is found in an extensive region from Morocco to Tunisia.

Bengasi area of Libya has also the steppe climate. The southern steppe region in Africa extends from Dakar in Senegal to Ethiopia.

In Kenya and Somaliland also low-latitude steppe climate is found in certain areas. Large areas in southwest Africa, Botswana and western Rhodesia fall into the steppe climate.

In Eurasia the low-latitude steppe climate is found in close association with the tropical deserts. Large areas in Anatolia Plateau, the high-lands north and south of the Iranian Desert and Afghanistan have steppe type of climate.

A large strip of land encircling the Thar Desert is placed in the steppe climate. The rain-shadow areas of the Peninsular India have also this type of climate.

Low-latitude steppe climates also occur in various parts of South America: north-eastern Brazil, coastal areas of Venezuela, leeward areas of Argentina to the east of the Andes Mountains.

In North America, the low-latitude steppe regions are found in the Central Valley of California, Southern Kansas and central Mexico.

Low-latitude steppe climate encircles the great Australian Desert. Steppe region is very extensive to the east of this desert.

Temperature:

Temperatures in low-latitude steppe climates are similar to those in tropical deserts. Because of dry winds, summers are abnormally warm and winters extremely cold. The annual average temperature is over 18°C.

However, temperatures in this climate vary according to latitude, altitude and distance from the sea. At Fort Stockton in Texas in the United States of America the annual average temperature is 18°C, while Daly Waters in Australia record an annual average of 28°C.

This type of climate is characterized by large daily extremes and ranges of temperature. Large diurnal ranges of temperature are mainly due to the meager vegetation cover and clear and cloudless skies.

Where the ground is covered with abundant vegetation, the diurnal ranges of temperature are likely to be comparatively less.

Precipitation:

Low-latitude steppe regions generally receive larger amount of rainfall than the tropical desert. These regions generally receive between 25 and 50 cm of rain annually. The annual average rainfall is, in fact, less than the potential evaporation.

Rainfall is not only meager, but is also highly variable and unreliable. The amount of rainfall for a number of years may be sufficient for agricultural purposes, but then there follows a dry period.

The pole-ward margins of the steppe climate that are near the Mediterranean climate receive most of their precipitation during winter.

The low-latitude steppe regions that occupy the transition zone between the deserts and the savanna climate receive their precipitation during summer. This is partly because of the pole-ward shifting of the inter-tropical convergence during the high sun period.

Winter is, however, dry. Total rainfall is less than the wet-and-dry savanna climate. Steppe regions near the savanna climate receive relatively more rains. The variability of precipitation is also greater than those regions which are in close proximity to the Mediterranean climate.

Natural vegetation:

Low-latitude steppe climate is characterised by grasses which are short and shallow rooted. But the nature of vegetation on the pole-ward and equator-ward margins is different.

Latitude, seasons, nearness to more humid climates and the amount of precipitation are the controlling factors in determining the amount and height of vegetation.

Towards the drier margins, grasses are found in patches, whereas towards more humid margins ground is fully covered with grasses sufficient for grazing the cattle.

Stunted trees, bushes and shrubs and short grasses are the characteristic vegetation of the low-latitude savanna climate.

Animal life:

In view of the larger amount of precipitation and abundance of shrubs and grasses, a larger variety and greater number of animals are found here than those in the dry and hot deserts.

Animals such as wild horses, bison and antelopes feed on grasses. Carnivores like wolves, foxes and coyotes are found in large numbers.

Besides, reptiles such as snakes, rodents and lizards inhabit the steppe regions. The most common animals in this climate are the feed cattle such as sheep and goats.