In light of recent discussion about global warming, people have seemed to forget about the science of how global warming occurs. To bring light to the discussion I am going to take a minute to walk the community through the process of why this theory exists and what can be done about it. The image included is used as a graphic chart to help me explain these processes that go into global warming. I will refer to the chart on the left as Chart #1 and the chart on the right as Chart #2. Here it goes!
In order to get to how global warming happens, we need to talk about our atmosphere, how the temperature system works within it, and how CO2 heats up our planet. Our atmosphere has a negative feedback loop that actually keeps our temperatures in check. This negative feedback loop, makes it so that temperature changes actually encourage stabilization back to the system's starting point. This is due to the Carbon Cycle on our planet. CO2 emissions from volcanic activity and humans puts CO2 into the atmosphere where it condenses in clouds and is rained out. This rained out water and CO2 mix then reacts with Earths crust to create runoff that goes into the rivers. This CO2 now in rivers moves to the ocean where it reacts with sea water to form minerals, which are buried in the seafloor. This seafloor later is moved into regions where volcanic activity occurs and is then emitted once again to repeat this cycle. The warmer the atmosphere, the faster this cycle is conducted. The colder the atmosphere, the slower this cycle is conducted. The storing of CO2 in the Earths crust through this cycle is often referred to as 'Weathering', which I will refer to it as in the rest of this post. This weathering is what creates a sort of thermostat for Earth and keeps the negative feedback loops in check. We like weathering because it removes this CO2 from the atmosphere. We want this because excess CO2 causes the planet to get warmer by absorbing heat that is trying to escape our atmosphere into space. The CO2 particles absorb and scatter this heat in all directions, one of those being back down to Earth's surface. This creates a heat trap that can build up with the addition of more and more CO2. Chart #2 draws out this negative feedback loop and how it works. If the planet gets warmer, then weathering rates increase, decreasing CO2, cooling the planet. Then once the planet gets cooler, the weathering rates decrease, increasing CO2, warming up the planet again. This cycle repeatedly continues.
But then, if this cycle is so great and awesome then why is global warming a thing? The cycle only works if weathering (CO2 output) and volcanism (CO2 input) are the only two major systems inputting/outputting CO2 into our atmosphere. The solid and dotted black lines represent the Earth when weathering and volcanism are the only two facts in the system, showing a nice and stable level of CO2, keeping our atmosphere at regular temperatures. However, as we know, humans are beginning to input extensive amounts of CO2 in the atmosphere, disrupting our balanced negative feedback loop that regulated our climate. The dotted grey line represents where the system moves to when human CO2 emission are accounted for. While this creates a stable system, this system happens to also contain a lot more CO2 in the atmosphere which makes it hotter. This is global warming. While the negative feedback loop will still occur around this new medium, the general atmospheric temperature will be higher. If human CO2 emission rates continue to grow, the planet will continue to shift our 'equilibrium' to temperatures that might not be suitable for us.
Lastly, I would like to address possible solutions for the this. These ideas are not all original ideas, however I do agree that they would all help. Reflecting more of the suns heat to cool down the earth would allow for our temperature to decrease and still allow our carbon cycle to continue the way it is. This would allow the system to continue to be stable but at a lower temperature. While the carbon build up would still continue, the heating of the Earth would not, giving us more time to figure out how to reduce carbon emissions. To reflect the suns heat, we would need to increase the albedo of Earth, which is how absorbent/reflective we are. Since darker colors have lower albedos (absorb more) and lighter colors have higher albedos (absorb less), whiter colors could be used in urban areas to decrease the incoming heat. We could also artificially increase the size of the polar ice caps, which are white and reflective. But most importantly, we could implement the use of solar power in areas with low albedos in order to fight off that absorption and benefit from green energy. This would help with both issues of increasing CO2 and the resulting heating. While this would be very expensive, I think it could be planet changing.
That is it for my discussion! Let me know in the comments any criticisms you might have have with my proposed solution or any questions about any of the topic I covered!
See the links below for sources about the topic that I referred to:
The first source explains further in depth the negative feedback loop and the CO2 cycle
The second source explains why and how we can keep CO2 levels stable
The third source talks about possible ways to keep the thermostat in check.