Climate has a huge impact on the life of every person. Almost everything depends on it - from the health of a single individual to the economic situation of the entire state. The importance of this phenomenon is also indicated by the presence of several classifications of Earth's climates, created at different times by the most prominent scientists of the world. Let's look at each of them and determine by what principle the systematization took place.
What is climate
Since time immemorial, people began to notice that each locality has its own characteristic weather regime, repeating year after year, century after century. This phenomenon is called "climate". And the science involved in its study, respectively, became known as climatology.
One of the first attempts to study it dates back to the three thousandth year BC. Interest in this phenomenon cannot be called idle. He pursued quite practical goals. After all, having more thoroughly understood the climate characteristics of different territories, people learned to choose more favorable climatic conditions for life and work (duration of winter, temperature regime, amount and typology of precipitation, etc.). They directly determined:
- what plants and when to grow in a particular region;
- periods in which it is appropriate to engage in hunting, construction, animal husbandry;
- what crafts are better to develop in a given territory.
Even military campaigns were planned taking into account the climatic features of a particular area.
With the development of science, mankind began to study more closely the features of weather conditions in different fields and discovered a lot of new things. It turned out that they affect not only what type of crops it is worth growing in a given region (bananas or radishes), but also on a person’s well-being. Air temperature, atmospheric pressure and other climatic factors directly affect the circulation of blood in the skin, cardiovascular, respiratory and other systems. Guided by this knowledge, even today many medical institutions began to be located precisely in those areas where the weather regime had the most beneficial effect on the well-being of patients.
Realizing the importance of this phenomenon for the planet as a whole and for humanity in particular, scientists tried to identify the main types of climate and systematize them. After all, coupled with modern technology, this allowed not only to choose the most favorable places to live, but also to plan agriculture, mining, etc. on a global scale.
However, how many minds - so many opinions. Therefore, in different periods of history, various methods were proposed to form a typology of weather conditions. Throughout history, there are more than a dozen different classifications of Earth's climates. Such a large spread is explained by different principles, on the basis of which certain varieties were distinguished. What are they like?
Basic principles for climate classification
The classification of climates made by any scientist is absolutely always based on a certain property of weather conditions. It is these characteristics that become the principle that helps to create a complete system.
Since different climatologists put various properties of the weather regime (or their combination) at the forefront, the criteria for classifications are different. Here are the main ones:
- Temperature.
- Humidity.
- Proximity to rivers, seas (oceans).
- Altitude (relief).
- The frequency of precipitation.
- Radiation balance.
- Typology of plants growing in a particular area.
A bit from the history of climatology
For all the millennia of studying weather patterns in certain areas of the planet, many ways have been invented to systematize them. However, at the moment, most of these theories are already a part of history. And yet they have contributed to the creation of modern classifications.
The first attempt to streamline weather data dates back to 1872. It was made by German researcher Heinrich August Rudolph Grisebach. His classification of climates was based on botanical traits (plant typology).
Another system, more formulated by the Austrian August Zupan in 1884, became more widespread in the scientific community. He divided the entire globe into thirty-five climatic provinces. On the basis of this system, eight years later another climatologist from Finland R. Hult made a more extensive classification, which already consists of one hundred and three elements. All provinces in it were named according to the type of vegetation or the name of the area.
It is worth noting that such classifications of climates were only descriptive. Their creators did not set themselves the goal of practical study of the issue. The merit of these scientists was that they most fully collected data on observations of weather conditions around the planet and systematized them. However, an analogy between similar climates in different provinces has not been drawn.
In parallel with these scientists, in 1874, the Swiss researcher Alfons Louis Pierre Piramoux Decandol developed his own principles by which it is possible to streamline weather conditions. Paying attention to the geographical zonality of vegetation, he identified only five types of climate. Compared to other systems, this was a very modest amount.
In addition to the above scientists, other climatologists created their typologies. Moreover, as a fundamental principle, they used various factors. Here are the most famous of them:
- Landscape-geographical zones of the planet (systems of V.V. Dokuchaev and L.S. Berg).
- Classification of rivers (theories of A.I. Voyeykov, A. Penk, M.I. Lvovich).
- The humidity level of the territory (systems of A. A. Kaminsky, M. M. Ivanov, M. I. Budyko).
The most famous climate classifications
Although all of the above methods of systematizing weather patterns were quite reasonable and very progressive, they did not take root. They have become the lot of history. This is largely due to the inability in those days to quickly collect climate data around the world. Only with the development of progress and the emergence of new methods and technologies for studying weather conditions did it become possible to collect real-time data on time. On their basis, more relevant theories have appeared, which are used today.
It is worth noting that so far there is no single classification of climate types that would be equally recognized by all scientists in any country in the world. The reason is simple: different systems use different systems. The following are the most famous and used of them:
- Genetic classification of climates B.P. Alisova.
- The system of L. S. Berg.
- Keppen-Geiger classification.
- Travers system.
- Leslie Holdridge Classification of Living Areas.
Alice's genetic classification
This system is better known in the post-Soviet states, where it gained its widest distribution, continuing to be used today, when most other countries prefer the Keppen-Geiger system.
This division is due to political reasons. The fact is that during the years of the Soviet Union, the Iron Curtain separated the inhabitants of this state from the whole world, not only economically and culturally, but also scientifically. And while Western scientists were committed to systematizing Keppen-Geiger weather regimes, the Soviet preferred the classification of climates according to B.P. Alisov.
By the way, the same "iron curtain" did not allow this, albeit complex, but very relevant system to spread beyond the countries of the Soviet camp.
According to Alisov’s classification, systematization of weather regimes relies on already identified geographical zones. In honor of them, the scientist gave the name to all climatic zones - both basic and transitional.
This concept was first formulated in 1936 and refined over the next twenty years.
The principle that guided Boris Petrovich in creating his system is division according to the conditions of circulation of air masses.
Thus, the climatologist B.P. Alisov developed a climate classification consisting of seven basic zones plus six transitional zones.
The basic "seven" is:
- a pair of polar zones;
- a pair of moderate;
- one equatorial;
- tropical couple.
Such a division was justified by the fact that the climate is formed throughout the year with the dominant influence of the same air masses: Antarctic / Arctic (depending on the hemisphere), temperate (polar), tropical, and also equatorial.
In addition to the above seven, the “six” transition zones - three in both hemispheres - belong to the genetic classification of Alisov’s climates. They are characterized by a seasonal change in the dominant air masses. These include:
- Two subequatorial (tropical monsoon zones). In summer, sometimes equatorial prevails, in winter - tropical air.
- Two subtropical zones (tropical air dominates in summer and moderate air in winter).
- Subarctic (arctic air masses).
- Subantarctic (Antarctic).
According to the classification of Alisov’s climates, their distribution zones are delineated according to the average position of climatological fronts. For example, the tropic zone is located between the areas of dominance of two fronts. In summer - tropical, in winter - polar. For this reason, it is predominantly located throughout the year in the zone of influence of tropical air masses.
In turn, transitional subtropics lie between the winter and summer positions of the polar and tropical fronts. It turns out that in winter it is under the predominant influence of polar, in summer - tropical air. The same principle is also characteristic of other climates in the Alisov classification.
Summarizing all of the above, in general, one can distinguish such zones, or zones:
- arctic;
- subarctic;
- moderate
- subtropical;
- tropical;
- equatorial;
- subequatorial;
- subantarctic;
- Antarctic.
It seems that there are nine of them. However, in fact - twelve, due to the existence of paired polar, temperate and tropical zones.
In his genetic classification of climate, Alice also highlights an additional characteristic. Namely, the separation of weather regimes according to the degree of continentality (dependence on proximity to the mainland or ocean). By this criterion, the following climate varieties are distinguished:
- sharply continental;
- temperate continental;
- nautical;
- monsoon.
Although the merit of the development and scientific justification of just such a system belongs precisely to Boris Petrovich Alisov, he was not the first to come up with ordering temperature regimes according to geographical zones.
Berg's landscape botanical classification
In fairness, it is important to note that another Soviet scientist - Lev Semenovich Berg - was the first to use the principle of distribution across geographical zones to systematize weather conditions. And he did this nine years earlier than climatologist Alisov developed a classification of Earth's climates. It was in 1925 that L. B. Berg voiced his own system. According to her, all types of climate are divided into two large groups.
- Lowlands (subgroups: ocean, land).
- Hills (subgroups: climate of plateaus and highlands; mountains and individual mountain systems).
In the weather conditions of the plains, zones are determined according to the landscape of the same name. Thus, in the classification of climates by Berg, twelve zones are allocated (one less than Alisov's).
When creating a system of weather conditions, it was not enough just to come up with a name for them, you also need to prove their real existence. Through many years of observation and fixation of weather conditions, L. B. Berg managed to carefully study and describe only the climates of lowlands and high plateaus.
So, among the lowlands, he identified the following varieties:
- The climate of the tundra.
- Steppe.
- Siberian (taiga).
- Forest regime in the temperate zone. Sometimes also known as the oak climate.
- Monsoon climate typical of temperate latitudes.
- Mediterranean.
- Climate of subtropical forests
- Subtropical desert regime (trade winds area)
- The climate of inland deserts (in the temperate zone).
- Savannah mode (forest-steppes in the tropics).
- Climate of tropical rainforest
However, further study of the Berg system showed its weak point. It turned out that not all climatic zones fully coincide with the boundaries of vegetation and soil.
Keppen classification: essence and difference from the previous system
Berg's classification of climates is partly based on quantitative criteria, which were first used by German climatologist of Russian origin Vladimir Petrovich Keppen to describe and systematize weather conditions.
The scientist made basic developments on this topic back in 1900. In the future, Alice and Berg actively used his ideas to create their systems, but it was Keppen who managed (despite worthy competitors) to create the most popular classification of climates.
According to Keppen, the best diagnostic criterion for any type of weather regime is precisely the plants that appear in a certain area under natural conditions. And as you know, the vegetation directly depends on the temperature regime of the area and the amount of precipitation.
According to this classification of climates, there are five basic zones. For convenience, they are indicated by Latin capital letters: A, B, C, D, E. Moreover, only A denotes one climatic zone (humid tropics without winter). All other letters - B, C, D, E - are used for marking two types at once simultaneously:
- B - dry zones, one for each hemisphere.
- C - moderately warm with no regular snow cover.
- D - zones of the boreal climate on the continents with clearly defined differences between the weather in winter and summer.
- E - polar regions in a snowy climate.
The separation of these zones occurs according to isotherms (lines on the map connecting points with the same temperature) of the coldest and warmest months of the year. And besides, by the ratio of the arithmetic mean annual temperature to the annual amount of precipitation (taking into account their frequency).
In addition, the classification of climates by Keppen and Geiger provides for the presence of additional zones inside A, C and D. This is due to the type of winter, summer and rainfall. Therefore, in order to most accurately describe the climate of a certain zone, the following lowercase letters are used:
- w - dry winter;
- s - dry summer;
- f - uniform humidity throughout the year.
These letters are applicable only to describe climates A, C, and D. For example: Af is a zone of tropical forests, Cf is a uniformly moistened, moderately warm climate, Df is a uniformly moistened, moderately cold, and others.
For "deprived" B and E, large Latin letters S, W, F, T are used. They are grouped in this way:
- BS - climate of the steppes;
- BW - desert climate;
- ET - tundra;
- EF - climate of eternal frost.
In addition to these designations, this classification provides for the separation of another twenty-three signs, based on the temperature regime of the area and the frequency of precipitation. They are indicated by lowercase Latin letters (a, b, c and so on).
Sometimes, with such an alphabetic characterization, the third and fourth characters are added. These are also ten Latin lowercase letters, which are used only when the climate of months (the hottest and coldest) of a certain territory is directly described:
- The third letter denotes the temperature of the hottest month (i, h, a, b, l).
- The fourth - the coldest (k, o, s, d, e).
For example: the climate of the famous Turkish resort city of Antalya will be denoted by a code such as Cshk. It stands for: moderately warm type without snow (C); dry summer (s); with the highest temperature from plus twenty eight to thirty five degrees Celsius (h) and the lowest - from zero to plus ten degrees Celsius (k).
This encrypted notation in letters has earned such a strong popularity of this classification throughout the world. Its mathematical simplicity saves time at work and is convenient for its brevity when labeling climate data on maps.
After Keppen, who published works on his system in 1918 and 1936, many other climatologists studied it to perfection. However, the greatest success was achieved by the teachings of Rudolf Geiger. In 1954 and 1961 he introduced changes to the methodology of his predecessor. In this form, it was taken into service. For this reason, the system is known all over the world under a double name - as the classification of the Keppen-Geiger climate.
Classification of Trevart
Keppen's work was a real revelation to many climate scientists. In addition to Geiger (who brought it to its present state), on the basis of this idea, the Glenn Thomas Trevart system was created in 1966. Although in fact it is a modernized version of the Keppen-Geiger classification, it is distinguished by Trevart's attempts to correct the flaws made by Keppen and Geiger. In particular, he was looking for a way to redefine mid-latitudes in such a way that they are more consistent with vegetation zoning and genetic climate systems. This amendment contributed to the approximation of the Keppen - Geiger system to a real reflection of global climate processes. According to Trevart’s modification, middle latitudes were redistributed immediately into three groups:
- C - subtropical climate;
- D - moderate;
- E is boreal.
Because of this, in the classification, instead of the usual five basic zones, there are seven of them. Otherwise, the distribution methodology did not receive more important changes.
Leslie Holdridge Living Area System
Consider another classification of weather patterns. Scientists are not united in whether it should be attributed specifically to climatic ones. After all, this system (created by Leslie Holdridge) is used more in biology. However, it directly relates to climatology. The fact is that the goal of creating this system is the correlation of climate and vegetation.
The debut publication of this classification of living areas was carried out in 1947 by the American scientist Leslie Holdridge. It took another twenty years to finalize it worldwide.
The system of living areas is based on three indicators:
- average annual biotemperature;
- total annual rainfall;
- the ratio of the average annual potential of the total annual rainfall.
It is noteworthy that, unlike other climatologists, creating its classification, Holdridge did not initially plan to use it for zones around the world. This system was developed only for tropical and subtropical regions in order to describe the typology of local weather conditions. However, later convenience and practicality allowed it to gain distribution throughout the world. This was largely due to the fact that the Holdridge system was widely used in assessing possible changes in the nature of natural vegetation due to global warming. That is, the classification is of practical importance for climate forecasts, which is very important in the modern world. For this reason, it is placed on a par with the systems of Alisov, Berg and Keppen - Geiger.
Instead of types, this classification uses classes based on a specific climate:
1. Tundra:
- Polar desert.
- Subpolar dry.
- Subpolar wet.
- Subpolar wet.
- Subpolar rain tundra.
2. The Arctic:
- Desert.
- Dry scrub.
- Humid forest.
- Wet forest.
- Rain forest.
3. Moderate belt. Types of temperate climate:
- Desert.
- Desert Scrub.
- Steppe.
- Humid forest.
- Wet forest.
- Rain forest.
4. Warm climate:
- Desert.
- Desert Scrub.
- Thorny scrub.
- Dry forest.
- Humid forest.
- Wet forest.
- Rain forest.
5. Subtropics:
- Desert.
- Desert Scrub.
- Prickly woodland.
- Dry forest.
- Humid forest.
- Wet forest.
- Rain forest.
6. Tropics:
- Desert.
- Desert Scrub.
- Prickly woodland.
- Very dry forest.
- Dry forest.
- Humid forest.
- Wet forest.
- Rain forest.
