[Geography Notes] on Ionosphere Pdf for Exam

The ionosphere and magnetosphere are considered as the regions of the atmosphere of the earth which contains a large number of electrically charged particles. These electrically charged particles are also known as ions and electrons. The radio waves are propagated through these particles as they are large enough. Extraterrestrial radiation that usually comes from the sun creates these charged particles. These are mainly made on the molecules of air and neutral atoms. The Approximate height of the ionosphere is around 50 km that is 30 miles above the surface of the earth.

               

         

Layers of Ionosphere

Traditionally, there are several different layers under the ionosphere. When the discovery of the ionosphere was done, it was found that there were many layers present. The layers were named D, E and F under the ionosphere.

Ionospheric Regions

D, E and F layers are best for structuring out the ionosphere. The level of ionization in the ionosphere changes with altitude. There are peaks in each level of the ionosphere which are called different regions or layers. Along with these regions, there is a C region also under the ionosphere. But the fact is that the ionization level is a bit low as compared to other regions. C region does not affect radio communications and radio signals. There are dissimilar regions under the ionosphere and they have different features and also affect radio signals differently. The ways these regions are created are also different.

D Region

When the surface of the earth is left behind after the skywave and starts moving upwards then the initial region that reaches the ionosphere is known as the D region. D region is present between 60 km to 90 km at altitudes. Several factors are dependent on when there is a loss of signal. The factors are the level of ionisation, frequency of the signal and frequency of the signal.

E Region

E region is considered as a step above the D region. The altitudes of the D region is between 100 km to 250 km. Wherever the existence of the E Region takes place, the air density will be seen less as compared to the D region. The reason why it happens is that the electrons are released out due to vibration and signals and then some of the collisions only occur. Hence the E region is somewhat not similar to other regions.

F Region

Among all the regions in the ionosphere, the F region is considered the most essential region in terms of radio communication. In the presence of the sun, the radiations are being released from the sun and most probably they are divided into two regions. Firstly, the F1 region is considered as the lower one and secondly, the F2 region is a higher one. If the infection point is taken into view then the F1 region will be considered. 

Some Facts about Ionosphere 

• The ionosphere overlaps the top of the atmosphere and the sun cooks gases there until or unless they lose an electron or two that creates a sea of electrically charged particles. Thus, this Ionosphere becomes the shelter to all the charged particles in the Earth’s atmosphere.

• The ionosphere stretches 50 to 400 miles above the earth’s surface and this is just right at the edge of space. Along with this the Ionosphere also forms the boundary between the Earth’s lower atmosphere where we can live and breathe in a proper way. So, the Ionosphere is the part where the earth’s atmosphere meets space.

• The ionosphere is the home to many of our satellites including the international space station. This means these satellites can be affected by the constantly changing conditions in the Ionosphere. This also includes the sudden swells of the charged particles which can increase the drag on satellites and shorten the orbital lifetimes.

• The ionosphere has a great role in everyday communications and navigation systems. For this reason, we are able to get the sound from Radio and GPS signals. In both cases, the Ionosphere’s composition and density can disrupt these signals.

• The ionosphere can be influenced by the weather. Different weathers like thunderstorm systems, hurricanes can create pressure waves that ripple up into the Ionosphere. NASA has done research on this matter and within the past 15 years, NASA satellites revealed the connections between the weather condition changes in Earth’s Ionosphere.

• Besides these, the Ionosphere can be influenced by the space weather and this glows constantly also.