Ionosphere the Earth’s atmosphere
Ionosphere the Earth’s atmosphere – The ionosphere, or ionosphere, is not a single layer, but a collection of several regions in the Earth’s atmosphere in which electrically charged (or so-ionized) regions, atoms, and molecules are relatively abundant. The sun’s intense X-rays and ultraviolet rays constantly collide with gas molecules and atoms in the Earth’s upper atmosphere. As a result of these collisions, some electrons are separated from their atoms, resulting in the formation of free electrons and ions with an electric charge (atoms that have lost electrons are called ions). As a result of this process, air changes from a gas state to a plasma state (ionized gas is called plasma). Ions (positively charged) as well as free electrons (negatively charged) are mobile and behave differently from the behavior of neutral (non-electrically charged) atoms and molecules; For example, they cause air (which has now shifted from gas to plasma) to become a powerful electrical conductor. Areas, where free ions and free electrons accumulate, are formed at different altitudes above the earth’s surface, but they are all called ionospheres together. In the following, it will be explained in more detail what an ionosphere is and where it is, and what its properties are.
Number of ionospheric regions in the Earth’s atmosphere – Ionosphere the Earth’s atmosphere
The Earth’s atmosphere has three main ionospheric regions called layer D, layer E, and layer F. These three areas do not have exact boundaries and their height also changes during the day and from season to season. Zone D is the lowest ionosphere, starting at 60 or 70 km above the Earth’s surface and extending to an altitude of 90 km. The next ionosphere is region E, which starts at an altitude of about 90 or 100 km above the earth’s surface and continues to an altitude of 120 or 150 km. The highest ionosphere is region F, which begins about 150 km above the earth’s surface and sometimes extends to an altitude of 500 km. Although each of the three ionosphere regions has different heights, unlike layers such as the troposphere and stratosphere, they are not separate. Rather, these ionized regions are connected by different layers of the Earth’s atmosphere. Zone D ionosphere is usually formed in the upper part of the mesosphere. The ionosphere of region E usually forms in the lower parts of the thermosphere. The ionosphere of region F also appears in the upper part of the thermosphere.
What are the properties of the ionosphere?
The ionosphere changes depending on various factors. The height, ionized particles, and even the presence or absence of ionosphere regions change with time. Some of these factors are explained below.
Ionosphere changes around the clock – Ionosphere the Earth’s atmosphere
The state of the ionosphere during the day is very different from that at night. During the day, the continuous energy from the sun’s X-rays and ultraviolet rays separate electrons from atoms and molecules. As a result, masses of free ions and electrons are formed. At the same time, some ions and electrons collide and recombine, returning to their original form. But at night, in the absence of sunlight, the recombination of electrons with their atoms intensifies, resulting in a decrease in the number of ions. Therefore, in most nights, zone D disappears completely and zone E is weakened due to the decrease in the number of ions. Every morning, when the sun shines on that part of the atmosphere, the X-rays and ultraviolet rays begin to work again. Therefore, the number of ions in region D and region E increases again. Zone F, the highest ionosphere, remains overnight. But during the day it is generally divided into two areas, one called the upper F zone or F2 and the other the lower F zone or F1.
Seasonal changes of the ionosphere
In addition to the daily changes of the ionosphere, these complex atmospheric regions also have seasonal and long-term changes. As the vertical axis of the earth deviates, the intensity of sunlight in different parts of the earth changes from season to season. And so the different latitudes of the earth are sometimes warm and sometimes cool. Also, by changing the location of the maximum X-ray and ultraviolet radiation of the sun on Earth, the ionosphere changes from season to season. This changes the formation of ions and their movement in different parts of the earth. Seasonal changes in the chemical composition of the atmosphere are also effective in this regard. And changes the rate at which electrons recombine with atoms, leading to a decrease in ions in the atmosphere. Sunlight varies less than 0.1% between the upper and lower limits of the sunspot cycle at visible light wavelengths. But the output of the sun’s X-rays and ultraviolet rays changes the throughput much more than the solar cycle, which varies from 0.1 to more. X-rays and ultraviolet rays play a key role in the production of ions that make up the ionosphere. Therefore, extensive changes in this type of radiation are very effective in increasing or decreasing the density of ions in the ionosphere. Large geomagnetic storms caused by solar flares and coronal mass ejection can also cause severe temporary changes in the ionosphere.
Aurora in the ionosphere
Above the Earth’s atmosphere, a magnetic bubble called the magnetosphere or magnetosphere surrounds the Earth. Most particles in the magnetosphere are ionized plasma. Electric and magnetic fields often generate a stream of charged plasma particles. Aurora borealis (top image) is caused by the collision of energetic plasma particles with gas particles in the Earth’s ionosphere. Plasma sometimes flows in the Earth’s magnetosphere in the direction of the Earth’s magnetic field and toward the polar regions. As a result, colored light is produced in the sky called the aurora borealis or southern and northern lights.
The ionosphere is widely used in the field of communication due to its properties. Also, as mentioned, the state of the ionosphere is not constant and is constantly changing. Therefore, it must be constantly monitored so as not to disrupt communication systems. The following are some of the applications of the ionosphere.