Steppe Climate – Temperate Continental Climate

Bordering the deserts, away from the Mediterranean regions & in the interiors of the continent are the Temperate grasslands
Feature semi-arid or steppe climate, which lies between the tropics & Polar Regions.
Though they lie in the westerlies wind belt, they are so remote from maritime influence that the grasslands are practically treeless.
Grass are generally distinct in natural vegetation as those lie in S-Hemisphere have a much moderate climate due to coastal effects of the seas & warm currents alongside
Whereas grasslands in N-Hemisphere are comparatively warmer in summers & colder in winters as they are entirely continental.

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In Eurasia, they are called Steppes, which stretches eastward from the shores of Baltic Sea across the Great Russian plains, to the foothills of Altai Mountains, for approx. 2000 miles
In isolated sections of Hungary & Mongolian-Manchurian region, they are known as Pustaz
In North America, the grasslands are quite extensive & known as Prairies, lying between foothills of Rockies & the Great lakes astride American – Canada border
In the southern hemisphere, due to the narrowness of temperate portions of southern continents, grasslands are rather restricted & less continental
In case of Pampas of Argentina & Uruguay, the grasslands extend right to the sea & enjoy much maritime influence
In South Africa, the grasslands are sandwiched between the Drakensberg & Kalahari deserts; & are further divided into the more tropical Bush Veld in the north, & more temperate High Veld in the south
In Australia, the grasslands are better known as Downs & are found in Murray-Darling basin of southern Australia

Steppe Climate

In northern hemisphere, they lie in the heart of continents & thus have little maritime influence
Hence climate is continental with extremes of temperature.
Summers are very warm, approx. 25* C, with winters are chilling cold, with well below freezing point viz. approx. – 20*C
Hence have high annual range of temperature
In contrast, in southern hemisphere, climate is never severe, with mild winters of ~ 10* C & warm summers with ~ 20* C, due to the maritime effect of the coasts
Hence annual range of temperature is way less than that in northern hemisphere steppes.
Annual precipitation in N – Hemisphere has a mean annual of approx. 50 Cm, with majority of rainfall in summers from convectional sources.
Winter rainfall of approx. 25 mm/ month is occasional by depressions of the westerlies & in form of snow.

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Due to maritime influence in southern hemisphere, mean annual rainfall always averages more than 50 cm, mainly due to warm ocean currents that wash the shores of steppe lands.
On the eastern slopes of the Rockies in Canada & USA, a local wind similar to Fohn (Switz), called Chinook, comes in south west direction to the Prairies, descending from the Rockies. It is a hot wind that rises the temperature & melts snow covered pastures, generally in winters & early springs, hence frequent chinook means mild winters in the region.

Natural Vegetation of Steppe

Natural vegetation of steppes is generally referred as temperate grasslands, differing only in density & quality of grass.
Their greatest difference from tropical savannas is that steppes are practically treeless & grasses are much shorter.
Regions in N – Hemisphere, where the rainfall averages above 50 cm, the grasses are tall, fresh & nutritious & are better described as long prairie grass
Examples include North America, Rich black earth of Russia –Ukraine & better watered areas of Asiatic steppe.
Where the rainfall is light, less than 50 cm, or the soil is poor, as in continental interiors of Asia, the short steppe type of grass prevails.
The grasses are not only shorter but also wiry & sparse, often found in discontinuous clumps, with bare soil exposed between them.

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The climatic requirement of grass are quite different from trees as they require less moisture than trees & an annual precipitation of approx. 25 – 50 cm is adequate.
Their growth is not abruptly checked by summer drought & winter cold as they lie dormant throughout this period & sprout instantly as soon as temperature is moist & warm again.
Trees are very scarce in steppes, because of the scanty rainfall, long droughts & severe winters; with long rolling plains of endless grass.
Poleward, an increase in precipitation gives rise to a transition zone of wooded steppes where some conifers gradually appear, but are very scattered & few in number.
Towards the equator, the steppe grass becomes shorter & sparser, till it merges into desert with thorny scrub.

Agricultural developments of Steppe

Grasslands have been ploughed up for extensive mechanized wheat cultivation & are termed as granaries of the world.
Beside wheat, maize is also increasingly cultivated, mainly in warmer & wetter areas.
Farms are extensively long, hence due to less attention & high mechanization, average yield per acre is low, but the yield per man is very high
Hence grasslands of mid latitudes produce greatest exporters of wheat in the world.
The tufted grasses have been replaced by more nutritious lucerne & alfalfa grass for cattle & ship rearing.

Natural conditions suit animal farming & with the introduction of more nutritious grass & refrigerated ships, temperate grasslands became major pastoral regions, exporting large quantities of beef, mutton, wool, milk, butter, cheese & other dairy products viz. Pampas became lead exporter of beef & Australia became world’s leading wool exporter.