EARTH’S ATMOSPHERE- STRATOSPHERE

Located between approximately 12 and 50 kilometres above Earth’s surface, the stratosphere is perhaps best known as home to Earth’s ozone layer, which protects us from the Sun’s harmful ultraviolet radiation. Because of that UV radiation, the higher up you go into the stratosphere, the warmer temperatures become. This layer is free of clouds and devoid of any weather-related phenomenon, but polar stratospheric clouds are sometimes present in its lowest, coldest altitudes. It’s also the highest part of the atmosphere that jet planes can reach. Due to this, aeroplanes fly in the Stratosphere for a smooth ride.  The Stratosphere is the layer of the atmosphere where there is the concentration of the Ozone layer, which acts as a protection from the UV radiation of Solar activity.

Ozone

Ozone is created in a natural and photo-chemical way in the stratosphere. Although it is a toxin in the atmosphere, it is vital for survival on Earth as it protects from potentially harmful UV rays. The mesosphere and thermosphere are two more layers of our atmosphere elevated from the stratosphere. Because there is essentially a disconnect of the mentioned layers from the other layers surrounding them, they have little impact on climatic conditions and pollution of transport systems. Pollution has little or no effect on these two highest levels as well.

Composition of Ozone

The stratosphere encompasses 9.9 per cent of the Earth’s mass of air and typically ranges between 10 km to 50 km, with ascending temperatures reaching -3. Because of precipitation in the earth’s atmosphere, H2O has a low chance of surviving directional transport. In this layer, solar UV rays can photolyse O2 to create ozone (O3), resulting in the “O3 layer.” To finish the Chapman cycle of O3 creation in the organic stratosphere, the O3 layer soaks slightly longer wavelength solar Ultraviolet radiation. Consequently, for wavelengths less than 300 nm, solar Ultraviolet rays at the upper edge of the stratosphere have more strength than the lower portion of the layer. Resulting in  life on earth remaining in protection from solar radiations

Ozone Hole

Chemicals that degrade slowly in the troposphere, such as Nitrous oxide and CFCs, may build to a significant level and reach the stratosphere through the stratosphere to troposphere interchange episodes in the present atmosphere. These compounds photolyse in the stratosphere due to high sun energy, forming Nitrogen Oxide and Halogen ions, which then disrupt the Chapman cycle, affecting the width of the Ozone layer. The much-discussed “Ozone3 hole,” first detected above Antarctica in springtime in the 80s, is the most interesting discovery relating to the Ozone layer in the stratosphere. Due to intense photochemical reactions, surface-derived chemicals such as CH4, N2O, and CFCs have lower mixing ratios in the stratosphere than in the troposphere. Meanwhile, reaction products such as NO, OH, and halogens ions can be higher in the stratosphere than part of the earth’s atmosphere.

At the top of the atmosphere, approximately 7% of the radiation is in the ultraviolet, 41% in the visible, and 52% in the infrared. The Degree of UV radiation that filters through and hits the earth’s surface is significantly lower than what it is at the topmost layer of the atmosphere—something in the atmosphere filters out energy. The highest-energy light is most effectively filtered out. This is very important because high energy light (gamma rays, x-rays, UV-radiation) penetrates the cells of living things and causes damage to them.

Conclusion:

The tropopause, which serves as a border for the earth’s atmosphere, lowest layer troposphere and stratosphere, marks the start of the stratosphere. Isothermal conditions prevail in the lower stratosphere. To put it another way, the temperature in the lower section of this sphere is unaffected by altitude. There may be a minor increase in temperature with elevation in some cases. This temperature area can be found up to a distance of 30 kilometres. Its circulation patterns are also persistent, as are the intense wind speeds. Cirrus clouds, often known as mother-of-pearl clouds, develop in the lower stratosphere on occasion. There are no apparent weather phenomena above the tropopause. Beyond 20 kilometres in altitude, the temperature gradually rises. The upper stratosphere is the name given to this area. In the summer, the stratospheric temperature rises with latitudes to the poles. But during the colder temperature, the stratosphere remains warm between 50°-60°. Over 60°, the temperature starts decreasing. The thickness of the stratosphere is highest at the poles. The upper boundary of the stratosphere is called the stratopause.