How many degrees in winter in the deserts of Africa. Why is it cold in the desert at night: types of deserts, features

The desert climate is characterized by hot summers and cold winters. The average annual temperature varies from +16°С in the northern part to +20°С in the south of the zone. Summer temperatures in western and eastern parts do not differ significantly, are 26-30°C.[ ...]

Synonym: desert climate with cold winters.[ ...]

Division of climates into 9 major groups listed below; these 9 groups contain 30 types. Main groups: warm climates without a dry period (equatorial), warm climates with a dry period (tropical), monsoon climates, warm temperate climates no frost period (subtropical), temperate climates with cold seasons, hot desert climates, cold desert climates, cold climates with moderate summers, cold climates without warm seasons. For climate groups, the numerical characteristics of the temperature and precipitation regime are indicated. Separate types of climate are geographically named according to the areas where they are most pronounced (Bengal climate, Norwegian climate, etc.).[ ...]

A. h. characterized by irrigated agriculture. A soils - are formed in the arid climate of deserts, semi-deserts, dry steppes and deserted savannahs, where the evaporation of moisture significantly exceeds its intake with precipitation. A-th climate - a dry climate in which the amount of evaporation greatly exceeds the amount of precipitation during the year; characterized by the clarity of the sky, high level condensation that prevents the formation of clouds, large daily temperature fluctuations. It is characteristic of deserts and semi-deserts.[ ...]

Our observations of benthos suggest that plant communities could be more diverse in a stable environment. The climate of the Sonoran Desert is distinctly erratic, with alternating two wet and two dry periods per year and high variability. total rainfall in different years. However, some parts of the Soiora desert are quite rich in species (see Figure 3-10). It turns out that in this desert instability natural conditions does not so much limit diversity as it turns into such an aspect of the environment to which plants respond by niche differentiation (see Fig. 3-7) and, as a result, by diversity of species. The vegetation of the Middle East has been greatly disturbed by man, it has been subjected to fires, logging, strong and varied pressure from grazing sheep, goats, large cattle and camels. But the structure of light forests and shrubs changed by grazing is nevertheless very rich in species that have adapted to these disturbances, especially species of annual and bulbous plants. The fact that warm climate plant communities in Sonora, the Middle East, and elsewhere are so rich in species despite drought and environmental instability suggests that temperature, more than moisture or stability, is the main factor that determines the species diversity of vascular plants. We can also mention one more observation of terrestrial plant communities, namely, broad-leaved deciduous forests, on average, are noticeably richer in species than evergreen forests. coniferous forests under similar environmental conditions. The type of dominant species that determine the nature of leaf litter and chemical composition organic matter soil, significantly affects the species diversity of terrestrial plant communities.[ ...]

The influence of greater or lesser air humidity on an animal organism can be expressed in a certain change in metabolism and the acquisition in the process of evolution of a number of adaptations to the peculiarities of the climate. A dry climate is more favorable for the body. The healing effect of mountain, steppe and semi-desert air is also partly due to its low humidity. The dry climate has a particularly beneficial effect on the wool of sheep (Merino sheep breeding); on the strength, energy and performance of horses (for example, oriental, genus - Arabic, Akhal-Teke). Animals of a dry climate (desert and semi-desert zones) over the centuries have developed an exceptional adaptability to these conditions (camel, antelopes, certain breeds of sheep, donkeys, etc.). Countries with high rainfall and high air humidity are more suitable for the development of dairy cattle breeding (forage crops and pasture plants grow well here). However, excessive air humidity adversely affects the health of animals, as well as some types of their productivity. Animals living in low, damp places are more likely to suffer from pulmonary, helminthic and some other diseases. Low temperature at high humidity air causes catarrh respiratory tract and intestines, especially in representatives of breeds unaccustomed to such a climate (for example, in steppe sheep when they are transferred to damp areas). In addition, under the conditions humid climate the coat and the quality of wool in sheep often deteriorate.[ ...]

Evaporative geochemical barriers / are areas where an increase in concentration chemical elements occurs as a result of evaporation processes. They are most common in regions with an arid climate (deserts, dry steppes and savannahs), but they are also found in the black earth steppes and even in the taiga and tundra. However, in this case, during the rainy period, the soil is washed out and the anomalous concentrations of chemical elements on the evaporation barriers may disappear.[ ...]

Anthropogenic activity significantly affects climatic factors, changing their regimes. Destruction of forests and other vegetation, creation of large artificial reservoirs on former territories land increases the reflection of energy, and dust pollution, for example, snow and ice, on the contrary, increases absorption, which leads to their intense melting. Thus, the mesoclimate can change dramatically under the influence of man: it is clear that the climate North Africa in the distant past, when it was a huge oasis, was significantly different from today's climate of the Sahara Desert.

The highest (up to 100 meters) dunes. Takyrs. The Gobi Desert in Mongolia. Karakum. Dunes. Deserts. sandstorms. Desert Victoria. sandy deserts. Deserts of the world. Kalahari. Dune. Great deserts of the world. Deserts of the Arabian Peninsula. Pictures of animals. Sahara. The largest oasis in the Okavango Delta. Peruvian Nazca Desert. main population. Salt marshes. Salt deposits. About 160 thousand mirages.

"Desertification of the Lands" - Lonely ship. The fight against desertification. Degraded areas. Reduction of agricultural areas. Desertification. Map of the desertification of the Earth. Desertification and land degradation. Sand barriers. Desertification types. Causes of desertification. Karakum Canal. Land degradation. Environmental consequences. Distribution in the Russian Federation. Dry lands. Human activity.

"Deserts of the Gobi" - Communities of steppe deserts. Linear dependency. Desert steppes are common in the piedmont plain. Biological potential of dominants and co-dominants in communities. Cold wormwood-serpentine-feather grass community. Mass renewal of Elijah. The annual dynamics of the one-year mass. Significant fluctuations of the above-ground mass. E.I. Rachkovskaya (1977) singled out extremely arid deserts. Distribution of plant communities and dominant species.

"Humidification of deserts" - Deserts in winter and summer. Nuclear COOLERs for the rehabilitation of coastal arid areas. Essence of the project. decline average annual temperatures. Plant. Construction of "Land-cooler". Sands of the Sahara. Upper clouds. Nuclear power complex. Abstracts. Deserts and global warming. arid territories. Spindrift clouds. Farmers throughout Africa. Complex structures. Water vapor in the atmosphere of the seas.

"Deserts of the world on the map" - Collared peccaries. Sahara. Unusual view jumper. Species composition of desert vegetation. Desert vegetation. Mountain ranges. Deserts of the world. Sun. Green rattlesnake. One-humped camel. Desert types. Deserts of the United States of America. Pronghorn. Oryx. Rocky desert. Inhabitants. Jerboa. Owl elf. American desert. Desert characteristics. Animals of the rocky desert. Deserts of Russia.

"Description of the desert" - The desert fauna has a protective "desert" color. Similarities and differences. Moisture deficiency, especially drinking water. Desert climate. Desert and arctic desert. Soil structure. Deserts. Human activities in the deserts. Xerophilous shrubs and perennial herbs. Desert animals and arctic desert differ significantly. Low temperatures air in winter. arctic desert devoid of vegetation.

Winter in deserts, although warmer than in the semi-desert zone, it is still unusually cold for these low latitudes. average temperature January in the north of the zone is about -12°, in the south - close to 0°, the average absolute minimum air temperature –35-20°. Lake Balkhash and the Aral Sea are ice-bound in winter; Freezing lasts 2.5-3.0 months at the mouths of the Amudarya and Syrdarya rivers. Snow cover about 10 cm high lies for 100 days in the north of the zone and 20-30 days in the southwest. The lack of snow and the short duration of the snow cover make it possible to graze cattle in the deserts in winter. The non-grazing period for sheep in the deserts of Kazakhstan lasts only 30-60 days, and in the Central Asian deserts it is practically absent, except for the relatively rare days here with ice and snowstorms.

Spring- the season of the year, refuting the usual ideas about the desert. At this time, there is a rapid increase in air temperature, unusual for other zones. In the area of Kyzyl-Orda, the crossing of the middle daily temperature air through 10 ° occurs on April 11, and after a decade or a little later, the transition of the average daily air temperature through 15 ° takes place there. May in the zone in terms of its temperature conditions (16-20 °) resembles the height of summer middle lane Russia - July. Moderate positive air temperature in spring is combined with the annual maximum of precipitation, which in the north of the zone falls in May, in the south - in April.

atmospheric precipitation along with winter supplies soil moisture is sufficient for a short-term, but lush development of vegetation. It was at this time that an outbreak of vegetation of ephemers and ephemeroids occurs, especially characteristic of sandy and foothill loess deserts. Becomes very active animal world. For some desert dwellers, spring is the only period of the year. active life. So, for example, the steppe tortoise is active only from March to May, after the ephemera burns out, it burrows into the ground and lies there until the next spring. A similar way of life leads a sandy gopher.

It is indicative that the lambing of goitered gazelle and domestic karakul sheep is timed to the moment of development of ephemeral-ephemeroid vegetation. At the same time, the growth of the Karakul lamb is characterized by a very high intensity in the first month. “The meaning of this phenomenon is that the lamb in the desert must be ready for the early dry summer, for eating dry hard grasses in summer, it is necessary to have time to work up a sufficient supply of fat.”

Summer in the deserts temperate zone even hotter, sunny and dry than in the semi-desert zone. The average temperature in July is about 25-29°, on some days the air temperature in the shade rises above 40°, and the surface of bare soil heats up to 70°. The hot period in the zone is stable and long: the number of days with an average daily air temperature above 20 ° in the north is 90, in the south - 140. The entire territory of the zone in summer serves as an arena for the formation of local continental tropical air, which differs not only high temperatures but also very low humidity and high dust content.

Exhausting heat is exacerbated by a negligible amount of precipitation, the amount of which is rapidly decreasing in southbound. For all three summer months 30 mm of precipitation falls in Irgiz, 19 mm in Kazalinsk, and 11 mm in Turkestan. For comparison, we point out that Moscow, with its moderately warm summer receives for the same period 192 mm of precipitation. Due to the acute lack of moisture, ephemera and ephemeroids disappear from the grass cover even before the beginning of summer, the most undemanding shrub wormwood and saltwort, which are in a state of semi-rest, stop growing. At the beginning of summer, the budding of cotton occurs, in July - its flowering, in late August - early September, ripening occurs.

Autumn in the first half it is very reminiscent of summer: in September, as in previous months, hot and dry cloudless weather prevails, favorable for the ripening and harvesting of cotton and fruit crops. In the southern half of the zone, the transition of the average daily temperature through 15° occurs around October 1. In the second half of autumn, cloudiness increases, the amount of precipitation increases, which, at low air temperatures, creates conditions for the re-vegetation (greening) of many plants. The first frosts in most of the zone appear in October.

Literature.

1. Milkov F.N. Natural zones of the USSR / F.N. Milkov. - M. : Thought, 1977. - 296 p.

Winter in deserts, although warmer than in the semi-desert zone, it is still unusually cold for these low latitudes. The average January temperature in the north of the zone is about -12°, in the south it is close to 0°, the average absolute minimum air temperature is -35-20°. Lake Balkhash and the Aral Sea are ice-bound in winter; Freezing lasts 2.5-3.0 months at the mouths of the Amudarya and Syrdarya rivers. Snow cover about 10 cm high lies for 100 days in the north of the zone and 20-30 days in the southwest. The lack of snow and the short duration of the snow cover make it possible to graze cattle in the deserts in winter. The non-grazing period for sheep in the deserts of Kazakhstan lasts only 30-60 days, and in the Central Asian deserts it is practically absent, except for the relatively rare days here with ice and snowstorms.

Spring- the season of the year, refuting the usual ideas about the desert. At this time, there is a rapid increase in air temperature, unusual for other zones. In the area of Kyzyl-Orda, the average daily air temperature passes over 10°C on April 11, and after a decade or a little later, the average daily air temperature passes over 15°C. May in the zone in terms of its temperature conditions (16-20 °) resembles the height of summer in central Russia - July. Moderate positive air temperature in spring is combined with the annual maximum of precipitation, which in the north of the zone falls in May, in the south - in April.

Atmospheric precipitation, together with winter reserves of soil moisture, is sufficient for a short-term but lush development of vegetation. It was at this time that an outbreak of vegetation of ephemers and ephemeroids occurs, especially characteristic of sandy and foothill loess deserts. The animal world is becoming very active. For some desert dwellers, spring is the only period of active life in the year. So, for example, the steppe tortoise is active only from March to May, after the ephemera burns out, it burrows into the ground and lies there until the next spring. A similar way of life leads a sandy gopher.

Summer in the deserts of the temperate zone, it is even hotter, sunny and dry than in the semi-desert zone. The average temperature in July is about 25-29°, on some days the air temperature in the shade rises above 40°, and the surface of bare soil heats up to 70°. The hot period in the zone is stable and long: the number of days with an average daily air temperature above 20° in the north is 90, in the south - 140. low humidity and high dust content.

Exhausting heat is exacerbated by a negligible amount of precipitation, the amount of which quickly decreases in a southerly direction. For all three summer months, 30 mm of precipitation falls in Irgiz, 19 mm in Kazalinsk, and 11 mm in Turkestan. For comparison, we point out that Moscow, with its moderately warm summers, receives 192 mm of precipitation over the same period. Due to the acute lack of moisture, ephemera and ephemeroids disappear from the grass cover even before the beginning of summer, the most undemanding shrub wormwood and saltwort, which are in a state of semi-rest, stop growing. At the beginning of summer, the budding of cotton occurs, in July - its flowering, in late August - early September, ripening occurs.

Literature.

1. Milkov F.N. Natural zones of the USSR / F.N. Milkov. - M. : Thought, 1977. - 296 p.

Deserts are one of the most interesting places on the planet, which is not surprising at all. These usually barren areas are home to rare species animals and plants, they have unique features in the question natural characteristics. These natural areas for many people seem mysterious and mystical. It is known that in some deserts the weather changes dramatically: the temperature drops or rises extremely in short periods of time. Why is it cold in the desert at night? Let's find out the main reasons.

Desert types

Before analyzing the specific reasons why it is cold in the desert at night, it is important to identify four main types of such terrain. There are hot and dry, coastal and cold deserts. Each of these types of natural areas has special weather conditions, only hot and dry deserts are subject to the aforementioned extreme temperature changes.

What's happening?

Hot and dry deserts are commonly found in the southwestern United States, South Asia, South America and Australia. These deserts can experience extreme temperature changes, with peaks reaching +44-49°C. While the minimum temperature can be -18 °C. So why is it cold in the desert at night?

A notable feature of the hot and dry desert is that they are not distinguished by dense vegetation. This leads to the fact that there are not enough plants and trees on the territory to absorb sunlight and save heat. In other words, when the sun sets and ceases to be a source of heat, there is nothing in the desert to keep warm, since this is the main task of plant life.

Why is it cold at night in hot deserts?

Hot and dry deserts experience concentrated rainfall, which usually occurs between longer periods without precipitation. In some seasons, such as winter, it is rare it's raining in hot and dry deserts. In some desert places, the annual rainfall is less than 1.5 centimeters. This results in a lack of moisture in the air. Moisture needed to block solar heat, without it, the temperature can reach + 49 ° C, as mentioned earlier. It also means that the lack of humidity means that the heat that the desert air saturates with during the daytime is not retained at night. This results in an extreme temperature drop. That's why it's cold in the desert at night.

Due to the lack of plant life and humidity, it is not surprising that hot and dry deserts can lose twice as much heat at night as similar non-empty natural areas.

Not all deserts cool off at night. In addition, during certain times of the year, the temperature difference may decrease. The air in deserts does indeed cool incredibly quickly, but only if there is no cloud cover (the clouds act like a blanket to keep warm), there is no wind and the air humidity is low. For example, Dubai is, in fact, a desert on the coast. Deserts located close to the sea certainly suffer from temperature changes, but the difference between day and night indicators is not critical.

Deserts that are far inland tend to have higher temperature fluctuations, but even in summer the night is never too cold.

Outcome

Thus, the question of why it is very cold in the desert at night is partially relevant. However, many people mistakenly believe that extreme temperature fluctuations are characteristic of all desert areas, when in reality this is far from the case. The most important factor in this matter is also a factor of geographical location.