What climate do you have?

The text continues the project on the Ecology "Variable" .

How to find out what weather awaits us, albeit in general terms and at least for the coming hours, without peering on the Internet? The sky will tell us about this: in the appearance of the clouds and the speed of the wind, you can figure out whether we should take an umbrella with us, leaving the house.

Where to look to determine the climate of a particular area? We agreed that we do not use search engines, encyclopedias and guidebooks, and our acquaintance university professor of geography, for example, excommunicated somewhere, so there is no one to tell. Looking out the window, we see the same sky, but we look out-and then a resident of Naryan-Mar sees a dwarf birch, which grew up among the tundra sedge, a guy from Belgorod is fascinated monitored by hogging in the steppe, in the Yakut region you can even close your eyes and listen to the wind in the crowns of pine and taiga Little bindings, not to mention crying, looking at the birch in the suburbs.

So, you have already guessed: the visiting cover for a particular terrain will be the hallmark of the climate. “If you want to know the weather - look at the sky, if you want to know the climate - look at the earth,” from year to year, he repeats at lectures on climatology at the University of Turku (Finland) the professor of geography of Yukka Kyuyukhkeo (CoLTA.RU talked with the professor about where to see the climate change). And since Flora is ready to tell us about the climate, it is logical that one of the most common climate classifications at the turn of the 19th and 20th centuries was developed by a botanist, Russian scientist Vladimir Petrovich Köppen.

Classification of Köppen to this day is widely used around the world, and it is based on two parameters: the temperature and the amount of precipitation. There are critical boundaries of the temperature: for example, representatives of the flora can grow only at a temperature above plus 5 degrees Celsius, but if the temperature rises higher plus 10, then the trunks of the future forest will rush up. In addition, the temperature of minus 3, which is important for plants, is considered the boundary of the stable snow cover. It was these threshold meanings that Vladimir Petrovich Köppen took the basis of his system.

Plants of plants, but also thought about people: several more temperature limits that are important for humans were taken into account in the classification. Plus 18 degrees are accepted for threshold value because if the mercury column drops below, you need to start heating at home. Plus 22 and minus 38 are taken for a thinner distinguishing between climatic zones, it is possible that even the non -specialists know for sure where to go on vacation and where not. After that, humidity was added to the average temperatures per month and over the year, depending on the amount of precipitation and the intensity of evaporation. It turned out a bright picture of the climatic zones of our planet, each of which was assigned a letter index.

The northern limits of Russia are in the field of the polar climate (index E ) with average monthly temperatures in the tundra, which never rise above 10 degrees. But the rest of the territory falls, according to the classification of Köppen, into the boreal climatic zone (index D ), where it is warmer, but the main feature is still cold winters: the average temperature of the warmest month in the year is more than 10 degrees (the forest, the cold-is not higher than minus 3 (Snow, Hurray!). In other words, we say - “boreal zone”, we mean - “snowy forests”.

In humidity, the eastern part of Russia is characterized by dry winter, in German it will be WinterTroCken , so Köppen added the letter W to the index: it turned out DW . It is here that the North Pole of the cold is located around the world and is the dispute between Oymyakon and Verkhoyansk, which is ongoing because of this title. Cold winter with medium (medium - not minimal!) The temperature of the coldest month less than minus 38 degrees adds a third letter to the index: DWD is obtained.

To the west of this kingdom of General Moroz, climatic zones pass through the territory of our country, which are inherent in moderate humidity throughout the year; For this, they receive the second letter F - from the word Feucht (from German - “wet”). The temperature diversity and, accordingly, the third letter in the index - a , b , C or D - in these territories even a beginner in climate matters will be pleased.

“If you want to know the weather - look at the sky, if you want to know the climate - look at the earth,” the professor of geography of Yukka Kyuyukhko repeats from year to year.

Extremely, the area of ​​incredibly cold winters - DFD (frost below 38 degrees). A little warmer in the climatic zone of DFC , where a short cold summer appears - in the language of meteorologists this is "less than four months with an average temperature of more than 10 degrees." In the next DFB zone, a warm summer, which pleases, for example, residents of Moscow (and sometimes not pleasing ). Warm but not hot, since the average temperature of the summer months does not exceed 22 degrees. But the summer is called the summer DFA , when the average indicators of the thermometer a month above 22 degrees.

As can be seen from the classification of Köppen, the type of climate is not described simply by the average temperature and the amount of precipitation. The climate is wider than the weather, since it includes, in addition to average, the maximum values ​​with minimal values ​​of meteorological variables, as well as their distribution during the year. According to meteorological data describing the climate for many years, you can monitor its change. To study the climate, scientists have chosen periods lasting 30 years.

Climatology would not be a science if scientists did not seek to explain the variety of climatic types and their geographical position. The everyday idea that it is cold in the north, and in the south it is warm, in the minds of scientists it turns out to be the dependence of the amount of solar heat on geographical latitude.

Imagine a shadow from the body of a person standing under a lantern, and an elongated shadow of the same stranger lit by the headlights of the car. The area of ​​the shadow from the light of the headlights is greater than the area of ​​the shadow under the lantern: the shadow “grows” when the angle is reduced between the direction of light and the illuminated surface. It also grows when moving to the pole and the area of ​​the earth's surface lit by the sun, because the angle - the height of the sun above the horizon - decreases.

If you smear the same pieces of oil for bread of different sizes, on a larger sandwich the oil layer will be thinner - so with solar energy: it will be less than closer to the pole, because the area covered with rays (shadow from headlights!) Becomes more. That is why more energy enters the equator than in high latitudes. So, the first engine of the climatic system of the Earth is the uneven heating of the planet.

Having received the energy of the sun, the earth radiates it. It is then that the greenhouse effect is turned on. If the atmosphere of the Earth did not serve as a “greenhouse”, that is, could not delay solar energy, if there were no carbon dioxide, water vapor, methane - the temperature on our planet would be 30 degrees lower.

Part of the energy warms our Earth, and the rest is radiated into space with the surface of the entire globe. Due to the uneven heating, an excess of heat is formed on the equator, and above 45 degrees north and southern latitude is its deficiency. Moderate and high latitudes do not live in means, that is, they receive less energy from the sun than they radiate. These scarce regions are obtained as a result of the redistribution of heat from equatorial regions to the north and south. It looks like a circulation of air masses and ocean currents. The distribution of continents and oceans, as well as the rotation of the Earth, are of great importance here. This is the second engine of the Earth’s climatic system.

The third key factor for the climate of the planet is the presence of permanent areas of low and high pressure. Often such areas are associated with jet currents - the so -called ultra -suffering air flows in the upper parts of the atmosphere, at an altitude of more than six kilometers. Airlines learned to use them to save aircraft fuel for long flights - like a fair wind. For meteorologists, such currents show places of the emergence of high regions (anticyclones) and low (cyclones) pressure, and also indicate the regions where the weather will be relatively stable.

The global climate change affects the above factors. For example, a change in the composition of the atmosphere - first of all, an increase in the content of carbon dioxide - affects the amount of heat, which is delayed on the planet. This leads to warming. The warming melts Arctic ice, and the exposed land and water surface reflects much less solar radiation compared to ice and snow, as a result of which heat and temperature growth accumulate. This is an example of positive feedback. There are negative ones: for example, ice melting reduces the salinity of ocean waters, which, in all likelihood, serves as one of the factors in the slowdown of the Gulf Stream, which carries heat in northwestern Europe. The slow gulf Stream cools the region and slows down the melting of ice - that is, the process extinguishes, and does not promote itself. Such feedback and the interaction of different factors are necessarily taken into account in climate models.

Already, according to the main parameters of the classification of Köppen, it is clear what the warming that we have been observed in recently can lead to. A temperature increase of several degrees can lead to transitions of threshold values ​​for specific areas: a stable cover (threshold minus 3 degrees) will not be obtained from dropping snow, and the forest will begin to grow where it was too cold for this (threshold plus 10 degrees).

The warming, which began after the invention of the steam machine of Watt (end of the 18th century) on stone coal and industrial revolution, in the geological history of the Earth falls on the intergulsis, that is, interglacial. This is a fairly short period of time (about ten thousand years) between glaciation. In total, the glacial periods in the history of the planet were twenty durations of one hundred thousand years. The reasons for the alternation of the glacial periods, scientists consider periodic fluctuations in the axis of the rotation of the Earth, a change in the parameters of the orbit of our planet, as well as variations of solar activity.

The last glaciation ended just ten thousand years ago, and according to the calculations of scientists, a cooling should take place at present - but we do not observe it. Human activity affects the climatic system of the planet so that the natural period of oscillations will be violated - and the three -letter “postal indices” of the earth's climate invented by the Russian scientist will have to be reviewed.