World Atmosphere Day 2023

N Munal Meitei *

The 10th April is observed as World Atmosphere Day. Our atmosphere seems tantalizingly close and yet mysteriously distant. The life-sustaining air we breathe envelops our planet like a pale-blue security blanket, clinging to us by the force of gravity. We see birds, an ever-changing patchwork of clouds and, in some places, air pollution. It's hard to tell where our atmosphere ends and space begins.

Earth's atmosphere is so much more than the air we breathe. The clouds we see in the sky, the wind that is moving the trees and even the sunshine we feel on our face—these are all a result of Earth's atmosphere. Earth's atmosphere supports the exchange of life-sustaining gases, filters sunlight, regulates temperature and even plays a vital role in soil and water cycle.

In fact, Earth's atmosphere is very thin, with a mass only about one-millionth that of the planet itself. But without it, life as we know it wouldn't exist. Not only does it contain the oxygen we need, but it also protects us from harmful solar radiations.

It creates the pressure without which liquid water couldn't exist on surface. And it warms our planet and keeps temperatures habitable for our living Earth. Without atmosphere, Earth would be a harsh, barren world.

There would be no weather at all without atmosphere. Weather makes life interesting. Weather also causes wearing down of rocks to form soils, the skin of earth. The atmosphere is an important reservoir for water, and the source of precipitation. Earth's atmosphere is composed of about 78% nitrogen, 21% oxygen, 0.9% argon and 0.1% other gases.

It consists of five major and multiple secondary layers. The major layers are the troposphere, stratosphere, mesosphere, thermosphere and exosphere. The secondary layers are the ozonosphere, ionosphere and magnetosphere. Each of these layers feature a unique composition and functions, contributing to safeguard the planet.

The chemistry of our planet's atmosphere provides a safe environment for plants and living beings to thrive. One of the main reasons why the atmosphere is important is that it protects the Earth from the vacuum.

Without the atmosphere, there would be no air, means no life. Besides, hydroxyl radicals enable the atmosphere to control the amount of pollutants and are responsible for the atmosphere's self-cleaning properties.

Atmosphere plays a key role in maintaining the earth's temperature. In fact, the coldest temperatures in the atmosphere are on the top of the Mesosphere, about minus 90°C and the hottest at upper regions of Thermosphere reaching 2000°C. The temperature on earth depends on the amount of energy entering and escaping from the Sun.

The Atmosphere, consists of greenhouse gases, such as carbon dioxide, methane, nitrous oxide and fluorinated gases. These gases trap heat to warm up the planet and preventing extreme temperature differences between day and night. Without them earth would have been an uninhabitable planet with around minus 17°C.

Without the atmosphere, our planet would be completely silent. As we know, the sound is a type of energy created by a vibrating object. As a matter of fact, without air, sound waves cannot travel through empty spaces.

Troposphere upto 12 km is responsible for water cycle containing 99% of all water vapor and aerosols. It consist around 78% of the entire atmosphere in this layer. Thus, without the troposphere, there would not be no rain and water. All human activities including the commercial Planes fly in troposphere as there the atmospheric pressure is pretty low, it enhances fuel efficiency, less turbulence and the ability to handle emergencies in time.

Stratosphere from 12 and 50 km protects life on the Earth from harmful ultraviolet radiation by the ozone layer. Ozone absorbs UV-B radiation from the sun, producing oxygen molecules and oxygen atoms.

The third layer, the Mesosphere from 50 and 80 km, is a physical protective layer that destroys most of the meteors, asteroids, rock fragments and other particles that can harm the Earth. According to Meteorology en Red, approximately 40 tons of meteorites fall toward our planet daily, but the mesosphere manages to burn them up before reaching the Earth's surface.

Thermosphere from 80 and 700 km is yet another protective layer of the atmosphere, without this layer, space communication would not be possible. According to NASA, thermosphere is home to low Earth orbit satellites and the International Space Station that orbits the Earth.

Ionosphere from 700 and 10,000 km is responsible for absorbing the extreme UV rays. It also reflects and modifies radio waves that we use for communication and navigation purposes. In the ionosphere, ions from the solar wind collide with the oxygen and nitrogen atoms from the atmosphere, releasing energy that leads to the formation of shimmery Gorgeous Aurora displays in the night sky.

There is no precise top of the atmosphere, but the area 100km above surface in Exosphere is called Karman line which is often considered the boundary between the atmosphere and space because 99.99% of Earth's atmosphere lies beneath this line.

Finally, unlike other important environmental aspects, air in Atmosphere is so vital that we can't be apart from air even for a minute. It's the key medium through which impacts of climate change are unfold. Air pollution is the cause for almost all of pulmonary and respiratory diseases. When we say, safe, healthy and supportive environments, it means the atmosphere. Atmosphere determine our health and wellbeing.

Therefore on coming World Atmosphere Day, 2023, let's take care of our earth's atmosphere for the sake of future generation.