Meteorological conditions mean the state of the atmosphere, which is usually characterized by air temperature, pressure, humidity, speed, and the presence or absence of clouds. Let's take a closer look at issues related to weather and climate.
General concepts and terms
When talking about meteorological conditions, they often use terms such as weather or climate. The weather is understood as the current state of the atmosphere, that is, it is clear or cloudy, cold or hot, the air is humid or dry, a strong wind is blowing, or there is a lull in a particular area. When they talk about climate, they mean a characteristic of atmospheric phenomena over a longer period of time, for example, summer or autumn climate.
Another difference between the concepts of "weather" and "climate" is the territorial factor. The weather may vary from place to place, for example, in a certain city it may be pouring rain, and at 20km from the city can be clear weather. Climate is a more extended characteristic not only in time but also in space. So, there are concepts of a tropical, continental or polar climate.
Why do different areas of the Earth have different climates?
The answer to this question is the spherical shape of our planet. This shape causes the sun's rays to fall at different angles on its surface. The closer the angle of incidence of the rays to 90o, the more the surface and air warms up. This situation is typical for tropical and subtropical zones. On the contrary, the further the angle of incidence of the rays deviates from the right angle, the less solar energy the soil and air receive, and the colder the climate. A striking example of a cold climate is the state of the atmosphere in Antarctica.
In turn, the difference in temperatures of the polar and equatorial zones of the planet leads to the appearance of winds, and also creates prerequisites for the formation of rain clouds. Different meteorological conditions in the latitudes of the earth lead to the appearance and disappearance of cyclones (areas of low atmospheric pressure) and anticyclones (zones with high air pressure).
The reason for the existence of the seasons
Every child knows from an early age that there are 4 seasons: winter, autumn, spring and summer. However, all these seasons, each of which is characterized by certain climatic and meteorological conditions, occur only in the middle latitudes of our planet. The strip of our planet, which is located from the 40th parallel of the southern to the 40th parallel of the northern hemispheres, has a tropical and subtropical climate, which is characterized by only 2 times or seasons of the year: wet and dry.
We figured out the reason for the different meteorological conditions in different latitudes. But why does the season change? The answer to this question lies in the tilt of the earth's axis of rotation relative to the plane of the earth's orbit. Our planet revolves around the sun in an almost perfect circle, and if there were no tilt of the earth's axis by 23.5o, then in each latitude the climate would not change during the year. The inclined axis of rotation of the planet provides fluctuations in the amount of solar energy entering the surface of the planet at each of its points during the year. These energy changes result in fluctuations in air temperature that are typically ±40°C. The maximum and minimum allowable temperatures are +58°C (El Azizia, Libya) and -89.2°C (Antarctica) respectively.
Note that the inclination of the axis of rotation of our planet has not been constant throughout the entire time of its existence. It is authentically known that during the existence of dinosaurs on Earth, it was definitely different. This slope can be influenced by both external factors associated with different cosmic bodies, and internal factors due to changes in the distribution of mass on the surface of our planet.
Favorable and unfavorable meteorological conditions
Often you canhear the words: "there is good weather" or "bad weather is expected in this region." What is the meaning of these phrases? To answer the question, here are the main parameters that determine the state of the atmosphere (to be precise, we need to say the troposphere, since it is in the lower part of the Earth's atmosphere that all weather phenomena occur):
- temperature;
- pressure;
- wind speed;
- air humidity;
- presence or absence of clouds.
The indicators of the above five parameters allow us to talk about both favorable and unfavorable meteorological conditions (NMU). For example, high temperature and pressure, too bright sun and low air humidity or, conversely, low temperatures, rain, high wind speed, low pressure - all these are NMU. Favorable weather conditions are usually characterized by average values for the above climatic parameters.
Main source of all atmospheric processes
Of course, the engine of all atmospheric (and not only) processes is solar radiation. It is she who makes many chemicals complete their cycle in nature. In relation to climate and weather, we can say the following: the rays of the sun falling on the Earth do not directly warm the atmosphere, first of all, the temperature of the lithosphere increases, then the hydrosphere. Cooling down, the lithosphere and hydrosphere emit infrared electromagnetic waves, which in simple terms are called "heat". Exactlythese waves heat up the atmosphere of the planet.
An important point in the formation of meteorological conditions of the habitat is the different rate of heating and cooling of the lithosphere and hydrosphere. So, the lithosphere quickly heats up and cools down, but for the hydrosphere, these processes are much slower. The reason for this different behavior in relation to solar radiation is their different heat capacity, as well as radiant power.
Other energy sources affecting the weather
Solar energy makes the main contribution to all processes occurring in the troposphere. However, there are other sources of energy that can influence the state of weather conditions in a particular area, and also ensure the stability of these conditions:
- geothermal energy and volcanic processes;
- respiration process and waste products of biological organisms that play an important role in maintaining a stable chemical composition of the atmosphere.
Atmospheric processes and their temporal and spatial scales
As noted, any processes in the atmosphere are associated with fluctuations in the amount of solar energy that enters the Earth. Due to these fluctuations, the air warms up and cools down day and night. This is a daily change in the weather. The processes of formation and melting of snow are already annual.
Heating air in a particular area leads to its expansion, which means a drop in pressure. A change in pressure leads to the formation of winds that tend toequalize the difference. They are of a different nature and in emergency situations can lead to the formation of hurricanes and tornadoes. In the latter case, one speaks of very difficult meteorological conditions. In turn, hurricanes are a short-term phenomenon of a certain area, that is, they are characterized by spatial and long-term temporal parameters.
Meteorological forecast
It is hard to imagine the modern world without information about the weather forecast in any region of the planet. Thus, aircraft flights, agricultural and commercial activities are increasingly dependent on meteorological data every year. For example, flight schedules change drastically during adverse weather conditions.
Meteorological forecast is the result of processing a lot of data using the most powerful computers that process the input information within the framework of some complex empirical model using the known laws of physics. Data on the meteorological conditions of a particular region is collected using strategically located weather stations on the ground, using satellites and unmanned aerial vehicles.
Study of atmospheric processes on other planets
Meteorology is an interdisciplinary science. The practical result of this science is meteorological forecasting. The complexity of the task itself is associated with the necessary consideration of hundreds and thousands of factors that affect the result of the forecast. For the bestunderstanding the influence of these factors on the weather of our Earth, scientists around the world are engaged in the observation and study of atmospheric processes on other planets of the solar system. For example, the Great Red Spot on Jupiter, which is a powerful anticyclone that has existed for over 300 years.
