rain ... snow ... piercing wind ... Scorching sun ... These manifestations Weather familiar to each of us with a deep childhood.But even diligent study geography in school, we still sometimes surprised by sudden changes in temperature and unusual natural disasters.With climatic shocks invariably associated atmospheric fronts.They form the daily weather and define the boundaries of the seasons.
atmospheric fronts
word "Front" (from the Latin "frontis" - the forehead, the front side) means a fine line between something.It can take place, for example, between different areas of operations: areas of concentration of enemy forces and friendly army.If we use the phrase "the atmospheric front," we mean the border in the air, a milestone in the atmosphere.What exactly he shared, and how does this affect us?
Mother Nature has formed a favorable climate in which people can live, reproduce and evolve.We live in the troposphere, the lower atmosphere, which not only gives us oxygen, and is in constant motion.Some volumetric mass of air in it from time to time interact.In the middle of each of these entities their small pockets microclimate, which differ in their properties, but generally are uniform, while maintaining a stable temperature and humidity.The masses move over the surface of the Earth, and there are even faced.But do not mix.The boundary between them is called the weather front.
main types
bandwidth between the same properties of air masses reaches tens, sometimes hundreds of kilometers.This atmospheric front, which always occur jumps in air pressure, cloud cover and temperature change.That is exactly in these areas you can see how to replace the hot sun comes cold rain and vice versa.If contact is very close, in fact homogeneous masses atmospheric front does not arise.As a result, the weather does not change.
There are several types of atmospheric fronts.They were formed on the basis of climatic zones, the major indices which remain constant.
- Arctic.Separates cold arctic air from the moderate.
- Polar.Located between the temperate and tropical air masses.
- Tropical.This is the boundary between the tropical and equatorial zones.
In the case of complete immobility air mass front would take a horizontal position.In this case, a layer of cold air was always to the bottom and warm - above.But as a result of the constant cycling it is disposed at an angle to the ground surface.
cold front
change of the weather in our region and what it will be - all these demonstrate the map of atmospheric fronts.It clearly shows that the warm front is always tilted in the direction in which the moving, cold - in the opposite direction.When the latter is moved to the high temperature zone, with a kind of gets into her wedge, pushing up on this territory comes cooling.Warm masses gradually cool down, out of which the moisture is released - so formed clouds and clouds.
first sign of a cold front is approaching rain cumulus formations that appear on the horizon.At the same time the wind blows in gusts, sharply changing direction.Wall torrential rain falls suddenly.The sky is dark, it cut through the lightning, thunder, hail goes sometimes.Bad weather does not last more than two hours, after which the precipitation cease.The air temperature is lowered, sometimes right in the 5-10 degrees, since the space atmosphere completely occupies the cold front, forcing the air warmed by the sun.
Warm Front
It is formed when a zone of high temperature plus "accumulates" on the cold ground.She seemed to glide over it, slowly rising.The weather is changing smoothly, without unforeseen surges and spikes.Cirrus clouds - the first sign that the approaching atmospheric front, in the center of which is quite high temperatures.Wind is not observed.If it is, then it blows always pleasant and easy.
clouds gradually melt, and the sky form a continuous white veil small layered structures that move at the clear blue sky.After some time, they bunch up: a dense layer is below, the wind picks up, a drizzle of rain or light snow falls.Precipitation strengthened, go a few hours, sometimes days, followed by a warming.Good weather lasts long.Front atmospheric, in which the temperature is low, catching up with the zone of heat, as is moving faster and steeper.
Cyclone
surface air is distributed evenly.As a result, formation of zones of high and low pressure.In the first region in excess of the air in the second - in the negative.From the high pressure zone it flows outwardly as would poured over the edge of the glass, and fills the resulting "hole" in the portion where the pressure is low.This natural phenomenon we call wind.
Plot low pressure it is the cyclone.It has the shape of a vortex.See how the water flows from the sink - it forms a funnel.The same principle shows us the weather.Cyclone - the same crater in the sink, but turned upside down.In its center pole of the low pressure that draws on all sides by an air and rushes up, with twisted it clockwise in the southern hemisphere and against - in the north.Inside the cyclone cloudy because with the wind, he "sucks" and a cloud.They are the hills roll into it from the zone where the pressure is increased.
Anticiklon
It works the other way around.In the center - high blood pressure, there is a lot of air, so it spreads out in all directions as if squeezed out of pastry cream package.Streams twisted clockwise in the northern hemisphere, against - in the south.Let us give another example: if you are lured into a tube carbonated drink, and then let go, he would invariably stechёt into the glass.A similar phenomenon occurs in an anticyclone.Only by using air and globally.
Weather anticyclone is usually clear, as high pressure displaces a portion of the cloud.This summer is always very hot: the obstacles in the form Tucek, preventing the sun to warm the air, no.In winter, the opposite is true.The sun is low enough, but the warm air, it can not: there are no clouds, and so nothing holds heat.As a result, in winter, when it comes to an anticyclone, the weather is clear, but frosty.By the way, studying atmospheric fronts, cyclones and anticyclones, their movements, changes and transformation forecasters make a forecast for the weather in a given region.
What will the future bring?
most difficult, say forecasters, the weather is foreseen for the next three days.That is, after collecting all the relevant information needed to process it quickly, taking into account all the vagaries of weather fronts, the changes of cyclones and anticyclones.Only by comparing the data, we can draw conclusions.
Weather forecasts are as follows:
- short - a maximum of three days.
- Medium-term - up to ten days.
- Weather - month or season.
first two types - the decision forecasters equations of thermodynamics and dynamics that describe the state of the atmosphere.The specialists analyzed the possibility of a change in wind direction, precipitation, alleged pressure surges and humidity.Weather never quite happens accurate.Even with the newest equipment, weather forecasters can not anticipate all the surprises prepared by nature.But be it in any way necessary, as in this forecast refers to the expected monthly or seasonal weather anomalies.
