Today’s lesson has been a fruitful one. I gained new knowledge on the Earth I live in. We learned about the lithosphere last year, so today, I learnt more about another part of the Earth’s system, the atmosphere and a little bit on the hydrosphere. So we all know that the atmosphere is composed of 78% Nitrogen, 21% oxygen and 0.05% carbon dioxide. Like what Mr Heah mentioned, every part of a system is there for a reason and with a proportion. What happens if any one part of the atmosphere disappears? Definitely not a good thing.
Carbon Dioxide, though occupies a very little percentage in the atmosphere, it is a temperature regulator. Without CO2, we will all freeze to death.
Nitrogen, an inert gas, occupies the largest percentage of the atmosphere, is important too. If there is no nitrogen, there will be an increase in percentage of oxygen and oxygen would become more concentrated, even though the amount of O2 doesn’t change. Oxygen being a reactive metal would react easily, forming oxides, which we won’t want to see it happen. If nitrogen disappears, pressure would also decrease and humans would burst up.
If oxygen is gone, we would just die because oxygen is a necessity to human life.
Another thing I learnt today is that the lithosphere, atmosphere and hydrosphere are abiotic. While the biosphere is biotic. Biosphere is basically living things. Living things regulate the a biotic region. For eg, in a volcanic eruption, CO2 is released into the air, which may result in global warming, the biotic part of the Earth would grow more plants to absorb the CO2.
In today’s lesson, I got a clearer picture on how our atmosphere sustains life and how the different parts of the earth are linked together.