Subsystems in unity for Earth’s prosperity

        In the previous week in the first quarter of Earth and Life Science, we discussed habitability and the uniqueness of our planet Earth. The second lesson features the subsystems that make Earth livable by working together. These are the atmosphere, biosphere, geosphere, and hydrosphere. I can't wait to look back, let's look deeper!

       The first in the pack is the one that I most know of, the atmosphere. The gaseous layer above the Earth’s surface is composed of 78% nitrogen, 21% oxygen, and 1% inert gases such as argon, carbon dioxide, carbon monoxide, ozone, etc. It has 5 layers which are: (1) Troposphere, (2) Stratosphere, (3) Mesosphere, (4) Thermosphere, and (5) Exosphere.  Our teacher explained that with the help of Atmosphere, life as we know it, exists! Animals and plants depend on the atmosphere for them to continue to exist. Also, I learned that this acts like a coat that retains heat from the Sun and protects us from harmful sun rays.

       Secondly, the biosphere! It was described as a zone where all life, like me, may it be in water, land, or air, exists. It is the thinnest layer of Earth and is sometimes called the large ecosystem. 

        Thirdly, the geosphere! The solid part of the Earth on which we're all standing! It is divided into 5 parts: inner core, outer core, lower mantle, upper mantle, and the crust.

        Lastly, the hydrosphere! The liquid part of the Earth such as glaciers and oceans. It is where I have learned that 71% of the Earth’s surface is covered by water! And in which 91% is composed of saline water and 3% of freshwater.

        These subsystems also interact with each other. An example of this is the carbon cycle, an interaction between the biosphere and the geosphere where plants in the biosphere absorb carbon dioxide from the atmosphere and convert it into organic matter through photosynthesis, cycling carbon between living organisms and Earth’s rocks and soil. Proof that these subsystems interact with each other to make Earth more livable or less livable.

        Indeed an integral part of our planet. Without these four and the factors of habitability last lesson, we wouldn't be living to tell the story of our planet. That's all, Ad Astra!