In this article we will consider what latitudinal zonation is and how it affects the location of natural zones on Earth. A comprehensive answer to this question is given in the school course of geography. But try to figure it out again. Let's get started.
We clarify what latitudinal zoning is.
The mentioned term is used to denote a natural change in natural conditions and physical-geographical processes as they move from the poles to the equator. In addition, latitudinal zoning extends to the ocean.
The law of latitudinal zonality was formulated by V.V. Dokuchaev in 1899. In general, it describes the location of natural zones in accordance with climate change. Since then, nature has undergone changes, but the laws are still relevant.
What is the main reason for latitudinal zonation?
To answer this question, we turn to the structure of the Solar system and the location of the Sun relative to the Earth. The sun's rays fall on the surface of the planet at different angles, respectively, the amount of solar energy received by different parts of the Earth is not the same.
This is clearly shown in the image below, which will easily help to understand what latitudinal zoning is.
Of course, this affects the climate. Compare, for example, the average annual temperature for Moscow and Lagos - the largest city in Nigeria.
Statistics show that in the capital of Russia it is about 5 ° C, while in Lagos it is about 27 ° C. The climate differences between these cities are partly due to different angles of incidence of sunlight. After all, Lagos is located close to the equator, and the rays are almost perpendicular to the surface, their energy is concentrated on a smaller area, which means that here the territory warms up more than in a temperate continental climate.
Geographical zones
Latitudinal zoning is the main reason for the formation of geographical zones. In addition, the deviation of air masses due to the rotation of the Earth around its axis, the proximity of the terrain to the ocean, etc., affect their formation.
We figured out what latitudinal zoning is, now let's talk about what geographical zones the Earth divides into. There are seven in total, including transitional ones. Let's take a brief look at each of them, starting from the equator.
Equatorial belt
The equatorial climate prevails here, characterized by high temperatures and humidity. Precipitation falls throughout the year. In the equatorial belt there is such a wind phenomenon as trade winds, which are formed due to the fact that, when heated, the air masses rise up, and cold air flows come in their place from the north and south.
The plant world is mainly represented by evergreen multi-tier forests inhabited by numerous representatives of the fauna.
Subequatorial belt
In the climate, seasonal changes are observed. Equatorial air masses prevail in summer, tropical masses in winter, so summer is characterized by increased humidity and temperature, and winter is characterized by low air humidity and almost complete absence of precipitation. The annual temperature amplitude is about 4 ° C. There are tropical monsoons.
Closer to the equator, the same evergreen forests grow. On the savannah they are replaced by shrubs, baobabs, tall grasses.
Tropical belt
A temperature difference appears:
- in winter - 10-15 ° C, less often - drops to zero;
- and in the summer - about 30 ° C or more.
The trade winds are operating again. In areas remote from the ocean, little rainfall occurs. Low humidity is almost everywhere.
Natural zones in the tropical zone are divided into tropical rainforests, savannas, tropical deserts. Interestingly, in tropical rainforests there are about 2/3 of the entire flora and fauna of the Earth, and some of the representatives are endemic.
Tropical deserts - the most arid zone of the above, which leads to a low amount of vegetation. Among the fauna reptiles predominate. The temperature during the day can reach 45-50 ° C, but nights are often cool.
Subtropical belt
On the territories of the subtropics, tropical air masses dominate in summer, and air masses of temperate latitudes dominate in winter, therefore, the boundaries of summer and winter clearly differ. There are monsoons.
The average temperature in summer fluctuates around 20-30 ° , in winter it can drop below zero, but mostly it is not lower than 3-5 ° .
In the subtropical zone, three types of climate are distinguished:
- Mediterranean;
- monsoon with a lot of rainfall in winter and summer;
- continental, characterized by dryness.
In the flora of the northern and southern hemispheres, differences are observed:
- Subtropical steppes are found in the northern hemisphere, and deserts and semi-deserts in places with a continental climate.
- In the southern hemisphere, steppes and broad-leaved forests predominate. Near the mountains and hills can be located forest-steppes.
Temperate zone
The climate of the temperate zone is divided into 4 types. Briefly consider each of them:
- Moderate marine climate. It is characterized by high humidity and high rainfall. Winters are mild, temperatures rarely drop below zero, summers are warm.
- The climate is continental. It differs in fairly cold winters with possible temperature differences (indications are widespread from -5 ° C to -30 ° C and below.) And warm summers with an average temperature in the region of 20 ° C, which can be either arid or rainy.
- Sharply continental climate. It is characterized by fairly warm summers (15–20 ° C) and severe, snowless winters. The temperature can drop to -40 ° C. Precipitation is extremely small, they usually fall in the summer. This climate is typical only for the northern hemisphere, since the territory of the continental sharply continental climate is almost completely occupied by the ocean.
- Monsoon climate. Monsoons dominate on its territory, which in summer bring precipitation from the ocean. And the winter season is dry. However, there are exceptions, as the geographical position also affects the amount of precipitation.
The temperatures in the northern and southern hemispheres are also ambiguous. Much is determined by geographic location. For example, in the northern regions of the Russian Far East in winter, the thermometer can drop to -20-25 ° . Summer is cool, only 15-20 ° C. In the southern hemisphere, winter is much milder. It also happens that the positive temperature here lasts almost the entire winter period. In summer, the temperature is close to zero.
Subarctic and Subantarctic
Subarctic and Subantarctic are belts in the northern and southern hemispheres, respectively. They are characterized by short summers with temperatures below 15 ° C and severe windy winters.
Humidity is usually increased. The area is occupied by swampy tundra, forest-tundra and taiga. Due to the poor soil quality and cold climate, plant and animal worlds are not diverse.
Arctic and Antarctic
The Arctic is a polar region adjacent to the north pole. The opposite area is Antarctica. These are permafrost territories. Nevertheless, in the Arctic, cyclones come and the temperature can rise to zero or slightly higher. The lowest temperature recorded in the Antarctic is -91 ° C.
Among plants, mosses, lichens, and tall shrubs are common.
Among the animals of the Arctic are reindeer, musk ox, polar bear, lemmings, etc.
In Antarctica, microorganisms live, a wide variety of penguins, small invertebrates.