§ 21. Hazardous atmospheric conditions and weather forecast
1. Remember that weather phenomena can be dangerous.
2. With devices which conduct monitoring of the weather station is?
Hazardous atmospheric phenomena. Earth's atmosphere ever affect life and work of the people. We largely depends on its composition and state of surface layer - the weather, from processes and phenomena that accompany it. Some human uses of benefit of themselves as climate resources. However, many among them such that can cause severe damage. Dangerous weather phenomena occur quite often suddenly show up as natural and cause significant damage to people and economy. Mostly they are connected with peculiarities of atmospheric circulation, sometimes influenced by the terrain. Dangerous phenomena that often in Ukraine include rain, fog, strong winds, heat, storm, snow, frost. Somewhat less dust storms occur, droughts, tornadoes, ice.
Storm - A short-term rainfall, during which sometimes falls monthly rate of rainfall for the area. Powerful storm jets and flows cause significant damage to an economy, pidmyvayuchy road and foundations of buildings, blurring the slopes of ravines. Summer rains come across Ukraine, but often - At the Carpathian Mountains, southern and southeastern areas. In the mountains they are more lengthy, sometimes cause disastrous flooding of rivers.
Frequently Showers accompanied by other unfavorable atmospheric conditions - lightning, hail and strong wind. During Thunderstormsin Cumulonimbus clouds or between clouds and land surfaces appear electrical discharge - lightning, accompanied by thunder. Period from thunderstorms starts in Ukraine in April and ends in September. But sometimes you can see lightning, even in winter. Thunderstorm can be dangerous for people and animals, can cause accident power line through the strain as a result of lightning strikes. For protect buildings from lightning strikes using lightning - Metal well grounded rods.
Most number of storms in Ukraine is the Ukrainian Carpathians. The record was 1951 during which there were 64 days of the storm.
Remember the rules of behavior during thunderstorms. You can not hiding under the lonely tree, lean against the wall of a tall building without lightning. If you find yourself in the box and you no where to hide, just pryhnitsya and perechekayte. Usually storm lasts long - up to 30 minutes. Must stand farther from the water - rivers and ponds. Very brave risk that think cheat rain zahovavshys in water. We know many cases when those swimming during a thunderstorm was struck by lightning.
In May - June storms accompanied Hail. In the central regions Ukraine it falls to 9 times per year. Grad - something transient, in most cases, the duration does not exceed 5 minutes. Still, in such a short time he causing extensive damage, damaging crops and fruit trees.
Mostly small hail falls. However, some hailstones can reach sizes of walnut with chicken eggs. Record high in Ukraine was hailstone weighing 500 g, and in the world - 7 kg!
Strong winds, that blowing at a speed exceeding 10 m/s, as observed during storms and revenues from the territory of Ukraine atmospheric fronts and cyclones. Especially dangerous storm (over 20 m / s) and hurricane (over 30 m / s) winds damaging the building, breaking trees, the overthrow oporytlines. In the Ukrainian Carpathians strong winds cause windfalls - overturning a tree.
Most wind speed in Ukraine - 180 km / h (50 m / s) - was recorded in December 1947 in the Crimean mountains Ai-Petrijajle in the world - 371 km / h in the U.S..
In thundercloud may occur tornadoes,that vertical air swirl to cover surface. They have View column diameter from several tens to hundreds of meters liykopodibnym expansion above. The air in the whirlwind revolves with great speed (up to 200 m / s), raising dust from the earth, water. In Ukraine there are tornadoes summer in a very heated air masses. Just as strong winds, they leave behind trail of destruction in several tens of kilometers. However, tornadoes are less than strong winds, and are much less territorial coverage.
Recent years due to warming climate in Ukraine increased heat - Bezdoschovi periods of high average air temperature. They are mainly in late spring and summer, the mercury from day to day rise to 30 °C and above. Hot weather people suffer, it causes ignition and burning peat, forests, dry vegetation in the desert.
The longest bezdoschovi periods in Ukraine, which lasted 115 days (almost 4 months!), were Poltava in 1934 and in 1948 in Kherson regions.
Continued bezdoschovi periods and low humidity and soil lead to drought, which result in dramatically reduced crop yields or they completely killed. Big drought covering more than half of the Ukraine, happen every 10 years, smaller - much more often. Often, they occur in southern and eastern Ukraine.
In these same regions of developing dry winds and dust storms. Winds - A hot, dry winds that speed over 5 m / sec. They occur in summer, blowing mostly from east and southeast of 1 10 days, taking moisture from the remnants of dried soil. Dust stormsarising in the arid weather and high speed wind, which blows dust and sand from the earth's surface and transfers them over long distances. They can last from a few tens of minutes to several days, severely compromising condition human habitation, causing significant losses to agriculture, work transport.
The strongest dust storms over Ukraine promchala end of April 1928 At that time, newspapers reported that over Dnieper steppes "raging sand storm unprecedented force. Dnepropetrovsk literally covered with dust. Institutions working day at the electric light”. About 15million t dry chernozem was flown in steppe and dispersed in the area 500 thousand km2, Including the territory of neighboring countries - Poland and Romania.
Fogs come across Ukraine for several ten days, more often - in the cold season. Most of them observed in mountainous areas in north and west. Especially dangerous to transport heavy fog when visibility is reduced to 50 m.
Fig. Fog on the Dniester border Ternopil and Ivano-Frankivsk region
Blizzard - Is the transfer of snow over land surfaces by wind. These often occur when moving over the territory of Ukraine Mediterranean and Atlantic cyclones. Worsening visibility and creating mounds of snow, blizzards create difficulties for a variety of modes. Tsyklonalna weather winter is also accompanied by strong snowfallwet snow sticking on the lines of communication that leads to breakages. In mountain areas due to intensive snow melting snow or active during the winter and spring thaw is climbing snow avalanches. They are very dangerous for local residents and Lovers of mountain tourism and winter recreation.
Most days storm in Ukraine - 71 days during the winter 1906/07 he was - registered in the Crimean mountains of Ai-Petri.
Cool companions period, is ice and ice. Black Ice - Is the formation of glacial cover on ground and various subjects as a result of freezing supercooled drops rain, mist or fog. Ice - Is the formation of such a crust on the surface land and roads as a result of cooling following the thaw. These atmospheric conditions are dangerous for the movement of people and transport, causing great damage winter crops.
Spring and autumn are often Frozen - lowering the temperature of air or ground to 0 ° C and below. Usually they to occur after 25 April and 16 October, but not uncommon, and May and the September frosts. They damage orchards and thermophilic cultures.
Weather prediction. Every day on radio, television, newspapers, the Internet, we get data about weather, which is expected shortly. Such information is important for each person and society general. Weather always changing, so it is important to be able to provide it. Extremely important to prediction of dangerous weather phenomena.
Drafting weather forecasts based upon the many information about the state of the atmosphere and laying surface. It regularly collects over 130 land-based meteorological stations located throughout Ukraine, and almost 30 aviameteorolohichnyh stations. Changes in weather there fix you all know by meteorological devices (thermometers, barometers, hygrometers, opadomira, wind vane, anemometer) and sophisticated technical devices. Messages from weather stations at certain intervals in the coming Ukrainian Hydrometeorological Center which is a component National Hydrometeorological Service of Ukraine located in Kiev. To make science-based forecast for the territory of Ukraine necessary to use meteorological data not only on our territory, and the whole Northern Hemisphere, so there is an exchange of information with other countries. Also used data space satellites.
В Meteorological are synoptic maps (maps forecast) for the territory of Ukraine, Europe, Hemisphere. They indicate the centers and directions of movement of cyclones and anticyclones, the location of atmospheric fronts, different elements and weather phenomena. In a series of synoptic maps determine how change of atmospheric circulation and therefore the nearest weather days or over a longer period.
In weather reports inform us of medical and meteorological situation the coming day. For many people, particularly the elderly, respond to meteorological conditions. The so-called meteozalezhnistmanifested by headache, decrease disability, worsening of mood, sleep disturbance, appetite, and sometimes pain in the heart, joints, back. There weather, three medical-meteorological types: friendly, relatively favorable, unfavorable.
Fig. Synoptic chart
Most in Ukraine are dangerous weather phenomena such as heavy rain, fog, strong winds, heat, storm, snow, frost, dust storms occur less frequently, droughts, tornadoes, ice.
Writer weather in the country engaged in Ukrainian Hydrometeorological Center which processes the information received from space satellites, domestic weather stations, weather services of other countries.
Questions and Tasks
1. What weather events in Ukraine are dangerous?
2. Injury could cause thunderstorms, rain and hail?
3. Where in Ukraine often have droughts, dry winds and Dust storms?
4. What hazardous atmospheric phenomena occurring in Ukraine in the cold season? How are they dangerous?
5. How is the weather forecast?