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0 Key Concepts to Understanding Climate Change Simplified
Most people who are somewhat educated on climate change know that carbon is a greenhouse gas. But how exactly does it trap heat? Science shows that the climate is changing, but isn’t the climate always changing throughout the Earth’s history? Water is also a greenhouse gas, so why don’t people ever talk about reducing water vapour emissions? There are a lot of scary scientific facts surrounding climate change, but without a proper understanding, people cannot properly act to combat their negative effects. Further still, when your family member is on the fence about “all this climate changing stuff”, you want to be able to explain why these statistics are a bad thing.
Carbon as a Greenhouse Gas – How it Works
Greenhouse gases are the main culprit of climate change. Like a greenhouse, they keep energy from escaping and make the inside get hotter and hotter. But how can an invisible gas keep this energy on Earth? And the reason lies in the fact that different kinds of light pass through greenhouse gases differently. The Sun sends radiation which has high energy, which CO2 is quite transparent to, meaning it lets most of it pass through the atmosphere and hit the Earth’s surface. The energy the Sun gives off is mostly visible light, which the Earth “catches”, heating surfaces, being used by plants to grow, etc.
But, the Earth can’t just hold on to this energy forever, so it has to give it back to space, or else the Earth would get much hotter incredibly quickly (enough to make life impossible). So, it sends the energy back up towards space. This radiation the Earth is sending back has lower energy (high wavelength) than the radiation it receives, mostly falling in the infrared part of the spectrum. But, CO2 is much more opaque to lower energy, absorbing most of the energy the Earth sends back towards space. CO2 then holds onto this energy for a little bit and sends it back in every direction, some of which ends up going back to Earth’s surface. So, with more CO2, less energy can go directly from Earth’s surface to space, because some of it is getting flung back. This is why the Earth gets hotter with greenhouse gases; less energy can escape from Earth to space.
Most people who are somewhat educated on climate change know that carbon is a greenhouse gas. But how exactly does it trap heat? Science shows that the climate is changing, but isn’t the climate always changing throughout the Earth’s history? Water is also a greenhouse gas, so why don’t people ever talk about reducing water vapour emissions? There are a lot of scary scientific facts surrounding climate change, but without a proper understanding, people cannot properly act to combat their negative effects. Further still, when your family member is on the fence about “all this climate changing stuff”, you want to be able to explain why these statistics are a bad thing.
The Changing Climate, All in Terms of Speed
When speaking to avid climate deniers, a main argument is often “The climate has been changing for millions of years, why does it matter now?”. And when you first think about this, it makes sense. The Earth has been hotter than today and colder than today. The atmosphere has had different compositions. But, what matters is the speed at which these changes happen. Nature needs time to be able to react to new environments to evolve and survive long-term. If warming, for example, is slow enough, then animals can migrate towards the poles and grow thicker fur coats. Most importantly, the interactions between species have the chance to re-balance based on changes and don’t crumble due to one species becoming too dominant or disappearing. When warming happens too fast, nature cannot keep up, so species die off and ecosystem dynamics get disrupted. The Earth is currently warming 20 times faster than the next fastest historical warming – after the previous ice ages. On the current path of greenhouse gas emissions, Earth will start to warm at 50 times the previous record pace. Earth’s complex and fragile webs of plants, animals, and fungi cannot handle this, and that means humans will suffer too.
Water Vapour Isn’t a Villain
There are many gases which have greenhouse effects like what was discussed earlier. Methane, CFCs, and water vapour are among them. But, water vapour stands out, since climate activists try to limit the emissions of the latter two. This is because they can stack up in the atmosphere, while water vapour cannot. When there is more methane released into the atmosphere, it just sits there, capturing energy that should be destined for space and sending it back to the Earth’s surface. But when more water vapour gets released from the land or sea, it doesn’t end up increasing the average amount in the atmosphere. This is because water rains out of the atmosphere and comes back to Earth when there gets to be too much vapour in the air. When there is higher humidity, the water will condense into a cloud, and then rain down onto the land or sea that it came from. So, on average, the amount of water that evaporates from the surface up into the atmosphere is the same as the amount that comes back down as rain. So, no matter how much extra water vapour you add, it will always come back down.
Water is unique in this ability since it is the only substance that can occur in all three states, solid, liquid, and gas, on Earth. Methane will stay as a gas no matter the temperature (at least for those temperatures achievable on Earth).
Final Thoughts
These facts are fun to know, but they also present an important step in the fight against climate change. If governments encourage their corporations to decrease their greenhouse gas emissions, so the corporations use less water vapour in their manufacturing and try to say they’ve reached their quotas of emissions, the government and citizens need to be able to call them out on their evasion. In terms of discussing with climate change skeptics, these facts can be used to show there is factual backing to government and social pressure to fight climate change. Of course, some people will simply deny science, and that’s how it’s going to be. But, for people who are just learning about climate change or those who have conflicting opinions, these facts can be crucial to their long-term understanding. Knowledge will always be an ally in our fight against a foe as complex as climate change.
Some Other Useful Facts
Why is ocean acidification bad?
It’s cold! Climate change can’t be real
Why is less biodiversity such a big deal?
Is sea level rise all that bad?
Works Cited
NASA. “The Water Cycle | Precipitation Education.” Gpm.nasa.gov, gpm.nasa.gov/education/water-cycle.
Nuccitelli, Dana. “Earth Is Warming 50x Faster than When It Comes out of an Ice Age | Dana Nuccitelli.” The Guardian, 24 Feb. 2016, www.theguardian.com/environment/climate-consensus-97-per-cent/2016/feb/24/earth-is-warming-is-50x-faster-than-when-it-comes-out-of-an-ice-age.
Rosen, Julia. “The Science of Climate Change Explained: Facts, Evidence and Proof.” The New York Times, 19 Apr. 2021, www.nytimes.com/article/climate-change-global-warming-faq.html.
Skeptical Science. “How Do We Know More CO2 Is Causing Warming?” Skepticalscience.com, skepticalscience.com/print.php?r=35.
UCAR. “Predictions of Future Global Climate | UCAR Center for Science Education.” Scied.ucar.edu, UCAR, 2021, scied.ucar.edu/learning-zone/climate-change-impacts/predictions-future-global-climate.
Key Concepts to Understanding Climate Change Simplified
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