This is an analogy that would explain the process and tipping point for dummies:
Imagine the climate of the earth is a huge, complicated, Mouse Trap Game/Rube Goldberg Machine designed to water your plants, feed your pet fish and hamsters and turn your thermostat up and down so the room stays a comfortable temperature.
Now imagine the whole machine is powered by the heat from burning candles, like one of those German Christmas toys.
The whole intricate system is running beautifully, your plants and pets are thriving and the room is nice and comfy. It’s like this most of your life.
But one day, one of the candles gets blown out, so the machine starts to malfunction. Maybe the plants don’t get watered as often and the pets don’t get fed so often. You don’t really notice because the machine has always worked, and even though the room doesn’t always feel quite as comfortable as it used to, you chalk it up to other reasons like what you cooked or hormones or something.
Meanwhile, since the hamsters aren’t getting fed as often, their energy level is off, and since the hamster wheel was powering the part of the machine that replaces candles, another candle goes out and now the machine really isn’t working well.
The fish aren’t getting fed, the plants are wilting noticeably and the hamsters are entirely inactive. On top of this, the room is getting uncomfortably warm because the machine can no longer adjust the thermostat properly and now the few candles that remain lit are melting just because the room is so damn hot. Soon the machine isn’t working at all and you’re busy putting out the small fires that have started from the melted candles.
Some little cactus plants survive and there are no doubt microorganisms eating your dead fish and hamsters, and live mold is growing too and some flies have gathered. So life hasn’t been wiped out entirely. It’s just a different form life that’s thriving because of the new, unintended environment.
You try to fix the machine, but can’t because you’re not the one who built it and it’s really complicated. Intricacies upon intricacies down to the microscopic level. Fixing it is completely beyond your pay scale. So now this place you lived your entire life in is uncomfortably hot, has bugs and mold and a funky smell. You can’t live there anymore, so you pack up your things to move to a new place.
When you open the door to leave, there is nothing there but an inconceivably vast and dark expanse that has no oxygen or heat. There is nowhere else you can go.
EDIT: Some people have PM’d me that they like this analogy enough to share it with younger folks. But this analogy doesn’t leave room for a solution, which is really depressing, so here’s more:
At this moment, we’re at the point where the second candle has just gone out. The hamsters are still fairly active, the fish are still swimming and only the most sensitive plants are showing signs of wilt. You still aren’t paying much attention, but you are noticing a strange noise you haven’t heard before. You search for the source of the noise and it’s a phone.
On the other end of the phone is a person telling you something is very wrong with your machine. They tell you your pets and plants are dying and if you don’t do something now you won’t be able to save them. (You look over at your pets and plants and they seem fine.)
This person says there’s a huge team of top scientists working hard around the clock to find a work-around to the malfunction, but he needs you to buy them some time by changing the way you live. Everything he says you have to change is incredibly inconvenient, not as comfortable and he’s even telling you to stop doing some of your favorite things– forever.
If you follow his instructions, your life will never be the same, but you will adapt and live out your days in the company of your beloved hamster, colorful fish and flowering plant. There’s even a chance that the scientists will call back in your lifetime and talk you through a way to patch the machine so it’s functional again.
If you don’t follow his instructions, one day soon the other candles will melt and it will be too much damage for the scientists to fix.
This is the moment we’re at today. The scientists have made the call and are working furiously to sequester carbon, find new viable and sustainable energy sources and perhaps even repair the damage to the environment. Even though they’re incredibly talented, they still aren’t the one who built the machine, so they won’t have a solution for a while. They’re asking us to change the way we live to buy them some time.
I hope this edit mitigates some of the gloom of the original ending. Candidly, I’m not sure how many candles have gone out. I’m really hoping the scientists can help us and that enough of us change the way we live to buy those scientists the time they desperately need.
PS. Thanks for the gold. PPS. Realized in this edit that the movie Apollo 13 is an incredibly good analogy for the balance between society/scientists in solving the climate crisis.
This is a really good explination for the emotional relationship to the whole thing. The key parts being that its is very complicated and hard to fix, and there is no where else like it. We can go to space, we can make versions of habitats that humans could survive in. But the simple but incredibly fucking important fact is, once we fuck this planet up, we wont be able to go back. Some version of life will continue, but probably not one we as humans can survive.
In the last 650k years, Earth has gone through 7 periods of glacial advance and retreat. The last was 7k years ago, marking the end of the Ice Age.
CO2 was demonstrated to trap heat in the mid 19th century. In the course of the last 650k years, Earth atmospheric CO2 levels has never been above 300ppm, and we know that through mineral deposits, fossils, and arctic ice leaving telltale predictable signs of how much CO2 must have been in the air at the time. Today, CO2 is over 400ppm. Not only have we kept fantastic records pre-industrial revolution, especially the Swedes for centuries, but arctic ice has acted as a more recent history of the last several dozen centuries. CO2 levels has been growing at unprecedented rates and achieving levels higher than we’ve ever known to occur that wasn’t in the wake of planetary disaster and mass extinction. It follows that if CO2 traps heat, and there’s more CO2 in the atmosphere than ever before, it’s going to trap more heat than ever before.
Sea levels are rising. 17cm over the last century. The last decade alone has seen twice the rise of the previous century. So not only are the oceans rising, but the rate of rise is increasing exponentially.
The Earth’s average temperature has increased since 1880, most of that has been in the last 35 years. 15 of the 16 hottest years have been since 2001. We’re in a period of solar decline, where the output of the sun cycles every 11 or so years. Despite the sun putting out less energy, the average continues to rise and in 2015 the Earth’s average was 1C hotter on average than in 1890. That doesn’t sound like much, but if we go some 0.7C hotter, we’ll match the age of the dinosaurs when the whole planet was a tropical jungle. That’s not a good thing.
The ice caps are losing mass. While we’ve seen cycles of recession and growth, you have to consider ice is more than area, it’s also thickness and density. Yes, we’ve seen big sheets of ice form, but A) they didn’t stay, and B) how thick were they? Greenland has lost 60 cubic miles of ice and Antarctica has lost at least 30 cubic miles, both in the last decade. Greenland is not denying global warming, they’re feverishly building ports to poise themselves as one of the most valuable ocean trading hubs in the world as the northern pass is opening, and it’s projected you’ll be able to sail across the north pole, a place you can currently stand, year-round.
Glacier ice is retreating all over the world, in the Alps, Himalayas, Andes, Rockies, Alaska and Africa.
The number of unprecedented intense weather events has been increasing since 1950 in the US. The number of record highs has been increasing, and record lows decreasing.
The ocean absorbs CO2 from the atmosphere. CO2 and water makes carbonic acid, – seltzer water! The oceans are 30% more acidic since the industrial revolution. 93% of The Great Barrier Reef has been bleeched and 22% and rising is dead as a consequence. The ocean currently absorbs 9.3 billion tons of CO2 a year and is currently absorbing an additional 2 billion tons annually. Not because the ocean is suddenly getting better at it, but because there’s more saturation in the atmosphere.
IPCC Fourth Assessment Report, Summary for Policymakers, p. 5
B.D. Santer et.al., “A search for human influences on the thermal structure of the atmosphere,” Nature vol 382, 4 July 1996, 39-46
Gabriele C. Hegerl, “Detecting Greenhouse-Gas-Induced Climate Change with an Optimal Fingerprint Method,” Journal of Climate, v. 9, October 1996, 2281-2306
V. Ramaswamy et.al., “Anthropogenic and Natural Influences in the Evolution of Lower Stratospheric Cooling,” Science 311 (24 February 2006), 1138-1141
B.D. Santer et.al., “Contributions of Anthropogenic and Natural Forcing to Recent Tropopause Height Changes,” Science vol. 301 (25 July 2003), 479-483.
In the 1860s, physicist John Tyndall recognized the Earth’s natural greenhouse effect and suggested that slight changes in the atmospheric composition could bring about climatic variations. In 1896, a seminal paper by Swedish scientist Svante Arrhenius first predicted that changes in the levels of carbon dioxide in the atmosphere could substantially alter the surface temperature through the greenhouse effect.
National Research Council (NRC), 2006. Surface Temperature Reconstructions For the Last 2,000 Years. National Academy Press, Washington, DC.
Church, J. A. and N.J. White (2006), A 20th century acceleration in global sea level rise, Geophysical Research Letters, 33, L01602, doi:10.1029/2005GL024826.
The global sea level estimate described in this work can be downloaded from the CSIRO website.
T.C. Peterson et.al., “State of the Climate in 2008,” Special Supplement to the Bulletin of the American Meteorological Society, v. 90, no. 8, August 2009, pp. S17-S18.
I. Allison et.al., The Copenhagen Diagnosis: Updating the World on the Latest Climate Science, UNSW Climate Change Research Center, Sydney, Australia, 2009, p. 11
Levitus, et al, “Global ocean heat content 1955–2008 in light of recently revealed instrumentation problems,” Geophys. Res. Lett. 36, L07608 (2009).
L. Polyak, et.al., “History of Sea Ice in the Arctic,” in Past Climate Variability and Change in the Arctic and at High Latitudes, U.S. Geological Survey, Climate Change Science Program Synthesis and Assessment Product 1.2, January 2009, chapter 7
R. Kwok and D. A. Rothrock, “Decline in Arctic sea ice thickness from submarine and ICESAT records: 1958-2008,” Geophysical Research Letters, v. 36, paper no. L15501, 2009
National Snow and Ice Data Center
World Glacier Monitoring Service
C. L. Sabine et.al., “The Oceanic Sink for Anthropogenic CO2,” Science vol. 305 (16 July 2004), 367-371
Copenhagen Diagnosis, p. 36.
National Snow and Ice Data Center
C. Derksen and R. Brown, “Spring snow cover extent reductions in the 2008-2012 period exceeding climate model projections,” GRL, 39:L19504
Rutgers University Global Snow Lab, Data History Accessed August 29, 2011.
I’m going to assume you’re at the center of mass for most “skeptics:” i.e. the planet is definitely getting warmer, but humans aren’t the cause.
Why is it so warm and cozy under your blankets in the morning? If you take your temperature before and after you get out of bed, is it any different? So if you aren’t any hotter, why is the air under your blankets so warm?
In order to warm up the air, you need energy to come from somewhere. If you don’t have electric blankets, the energy doesn’t come from there. Your temperature isn’t any different, so you aren’t making any more energy than normal. If energy isn’t coming from anywhere, than the only explanation is that less energy is leaving. The earth’s atmosphere works in the same way.
Slightly more advanced version.
I’m assuming that we’ve established that Earth has been getting hotter, as that is where most of the populace seems to be sitting. So…
Premise 1: surface temperatures of Earth are increasing.
Premise 2: There are only three possibilities to explain this:
- More energy is entering Earth
- Energy is moving from somewhere else on Earth to the surface
- Less energy is leaving Earth
Possibility 1 used to be very popular, with its proponents claiming that solar activity was increasing, thus increasing the amount of energy entering Earth. This was bolstered by a slight increase in sunspot activity going into the 90’s. The trend has since reversed. Since the sun is, for all intents and purposes, the only energy source of our planet, this establishes pretty well that 1 is not possible.
- More energy is entering Earth
- Energy is moving from somewhere else on Earth to the surface
- Less energy is leaving Earth
This is where most skeptics sit now, with the common claim being that current climate changes are a “natural cycle.” Considering that the biome has changed numerous times over the course of Earth’s history, this “cycle” can only be astronomical, geological, or oceanological in nature. We’ve ruled out the sun, and ocean temperatures are increasing as well overall, so that leaves geological. That’s been studied as well, and it doesn’t come close to explaining the energy change.
- More energy is entering Earth
- Energy is moving from somewhere else on Earth to the surface
- Less energy is leaving Earth
This is the definition of greenhouse gases. They build up in the atmosphere, preventing solar energy from leaving the earth, and forcing it to stay as excess heat. I have yet to see a skeptic argue that increasing greenhouse gases are notanthropogenic in nature.
There are many other levels of climate change “skepticism,” ranging from a ridiculous denial that things are getting hotter to a more reasonable, but still dangerous, disbelief that it will be problematic in the future. I can cover those as well, if you’d like.
Have you ever opened a car door during a hot day, probably in the summer? Notice how when you do, the inside is really hot? That’s because light is going through windows, but when it bounces back, it isn’t all getting out. The heat inside the car has nowhere to go either since it’s not (properly) ventilated. So it gets hotter and hotter. The longer you leave your car in the sun, the hotter it gets.
Greenhouse gases are essentially the windows. They’re molecules in the air and when sunlight enters Earth’s atmosphere, hits something, and goes to bounce back, some of it is caught in the gases. This means the heat stays there. When the heat stays there, it means things are getting hot.
In and of itself, that’s not bad. However, small temperature increases for the entire world cause massive changes everywhere. If warm winds shift to another area, this means entire weather patterns are affected. Rainfall changes (more, or less). If it’s hot, the ice melts at the north and south poles. When this happens, it turns to water, and that water is added to the sea. Hence the sea rise.
Here’s how CO2 traps heat:
There are different types of light and humans can only see ‘visible light’. Light with a shorter wavelength (like ultraviolet/UV) or a longer wavelength (like infrared) is invisible (for human eyes).
If light hits matter, a few things can happen:
- It can pass without interaction (so the thing is transparent).
- It can get reflected (light stays exactly the same, but starts moving in another direction).
- It can get absorbed and then emitted as fluorescent light
- It can get absorbed, making the matter hotter.
If matter has a higher temperature than absolute zero, it will always emit some light as thermal radiation. The hotter it is, the more light it emits and the shorter the average wavelength will be. Example, humans emit light because they are hot, however this light has a too high wavelength to see with your eyes. But if you use an infra-red camera, you can see this light. Another example: molten iron and other metals are really hot. So hot that they even emit thermal radiation with a short enough wavelength that it’s visible to humans.
The same happens with earth, if sunlight hits it, some gets reflected back (not changing the temperature), and some gets absorbed (making the earth hotter). The earth also emits a lot of invisible infrared light from being hot (thermal radiation).
Sunlight is a mix of all kinds of light. If it goes towards earth, first it has to pass the atmosphere a first time, then some gets reflected or re-emitted as thermal radiation, and then this light has to pass the atmosphere again to leave earth.
The more light that gets absorbed by the earth or the atmosphere, the hotter the planet gets. The more light that leaves earth again, the colder the planet gets.
What CO2 does is absorbing infrared light really well. If there’s a lot of CO2 in the atmosphere, this thermal radiation that the earth emits, gets absorbed by the atmosphere and will not leave the earth. Because more energy stays on earth and in the atmosphere, the earth gets hotter when there’s more CO2.
Humans have put more and more CO2 in the atmosphere, so more energy stays on earth and does not leave the planet, so more energy stays in and the earth gets hotter.
Way late to this, but if there are still any folks in the field lurking around and sorting by new, I have a question: one of the most convincing pieces of evidence I have heard (source: podcasts, random reading, Brian Cox, etc.) is that the carbon we emit via fossil fuel burning has a specific known ratio of C 12/13/14 isotopes. And as the concentration of carbon in the atmosphere increases we see the isotope ratios in the CO2 drifting from the natural ratios towards the ratios we are known to be emitting, proving that the additional CO2 we are measuring the atmosphere is ours. (I am not a skeptic) and to me this seems unbelievably convincing, if true, at least of the fact that what we burn is having a significant impact (since a lot of folks seem to think it’s something else unrelated to our carbon that is causing the warming). However, googling it some of the sources I’ve found for this info seem dated (think like 2010 or something) and I don’t see it brought up in any of the top-voted answers. So my question: can anyone in the field clue me in on why this isn’t a more widespread topic? It seems incredibly convincing, but I don’t want to spout it as evidence of climate change if it’s not cutting edge and totally accurate.
My favorite ELI5 explanation of global warming is this article.
Imagine you picked random numbers, over and over and over again. Frequent numbers would come up fast, and less frequent numbers would come up slower. Most of the really weird numbers — very high or very low — wouldn’t come up for a long time. But if the numbers were picked truly at random, you’d be just as likely to see a record high number as a record low number.
That’s what temperature should look like that. We’ve been taking temperatures in lots of places for a really long time, so setting a record (high or low) should be something that doesn’t happen often. When it does happen, it should be just as likely that it’s a record high temperature as a record low temperature…unless the “likely temperature band” is moving in one direction or another. And sure enough, when you look at the 1910 to 1960 period, when a temperature record got broken it was just as likely to be a new record low as a new record high.
However, researchers found that in the last fifteen years, when a temperature record gets broken — any temperature record, anywhere in the world — it was TWELVE TIMES MORE LIKELY that the new record was a new record HIGH temperature as it is that it was a new record LOW temperature. That indicates that things have changed — suddenly, and significantly.
The most ELI5 video I know of is one by veritasium: https://www.youtube.com/watch?v=OWXoRSIxyIU&app=desktop
Also, note that there is even proof that it’s caused by the use of fossil fuels: we know that fossil fuels have a different concentration of radioactive carbon than the atmosphere, and we can see that affecting the concentration in the atmosphere.
Whats the hottest planet in our solar system? Mercury because it is closest to the Sun?…nope.
the correct answer is Venus..and the reason why is because it has a thick CO2 atmosphere that traps the heat on its surface from going out into space, unlike Mercury which has no atmosphere.
the C02 levels on Earth has increased A LOT in the past 100 years because of cars, industry and such so naturally the surface is and will keep getting warmer.
There are a few parts. The shortest answer is that we’ve observed rapid warming, and explanations other than CO2 don’t really fit this trend.
To be more specific, over the past several decades, temperatures have been going up very quickly. No natural process we are aware of matches this temperature change in a way that would suggest causation. And, this change is much faster than temperature changes we’ve seen elsewhere in the historical record.
However, increased carbon dioxide in the atmosphere as a result of industrialisation and other human activity does correlate with this increase in temperature.
Looking historically, we have found that carbon dioxide and the sun are the biggest drivers of long term changes in the climate. So we’d expect that increased carbon dioxide could have this effect on the climate. We also know chemically that atmospheric carbon dioxide traps heat at different wavelengths than, say, water vapor, so we’d expect more carbon dioxide to lead to more heat being retained.
If you have time, search YouTube for potholer54 and his climate change series. He gets snarky at times (as youtubers tend) but his climate change series—especially the early videos—does a good job of laying out the basic arguments
This is actually VERY simple to prove, ON YOUR OWN, with fairly cheap materials.
Materials: * two identical sealable glass containers. * A bottle of CO2 (something like this, with a valve): https://www.amazon.com/Pro-Bike-Tool-Compatible-Cartridges/dp/B017KU1DIK/ref=pd_lpo_468_bs_t_2/163-4449439-2785660?_encoding=UTF8&psc=1&refRID=5D5Y7ABA6F038QKY8WP7 * A digital laser temperature sensor gun: ( https://www.amazon.com/Non-contact-Digital-Infrared-Thermometer-Temperature/dp/B01D1DFXZY/ref=pd_day0_469_2?_encoding=UTF8&pd_rd_i=B01D1DFXZY&pd_rd_r=ESVZVKWCF3VKSG8K584Z&pd_rd_w=yZBDJ&pd_rd_wg=cNBi5&psc=1&refRID=ESVZVKWCF3VKSG8K584Z )
Procedure: 1. Fill one container with CO2. You don’t even have to be super careful, since CO2 is heavier than air, just let it “pour” into the container, and close the top after you think it’s full. 2. The other container is filled with regular air. 3. Set both containers outside in the sun, on a sunny day. 4. Every 30 seconds, measure both containers with the thermometer, and write down the numbers on a piece of paper.
Expected Result: You will certainly see the CO2 container get warmer much faster.
Background: Now, take a commercial plane trip, and fly into a large urban center, like Los Angeles. Note that you’re flying about 400-600 mph. Look out the window on your approach and observe all the cars stopped on the highway. Each one is continuously spewing out large quantities of CO2. This happens all day long, every single day of the year. Yes, our earth’s atmosphere is vast. But you keep pumping this stuff out day after day, and after a few decades, it starts to build up.
That’s global warming, in a nutshell. It is VERY simple to prove it for yourself. There are complex ways in which the earth’s climate heats up and cools down, but this is how it works, in a nutshell. More CO2, more heat. The length of the day remains the same, and heat absorption goes up during the day. The length of the night remains the same, but the atmosphere retains more of that heat, so we will continuously build up heat, and get further and further behind, every day, as that heat is trapped and can’t radiate away to space. And as the air gets more CO2, the problem gets worse.
This property (the heat-retention of gasses) has been known about since roughly the late 1850’s. What we did not know, was how fast our population would grow, or how much industrial output of CO2 there would be. By the 1950’s it was pretty clear what direction we were headed in. By the 1970’s, most scientists did agree that this was a problem, and was happening, but they didn’t really all agree on what the time-scale would be. Since the mid 1990’s when we’ve invested in observing data more (satellites, weather instruments, computer simulations), we’ve become more and more certain that this is a real, and immediate problem.
Carbon dioxide is a green house gas. This is proven and is not up for debate.
burning hydrocarbons release a lot of CO2. Also a proven fact and not up for debate.
CO2 levels are higher now than they ever have been before and it started spiking in the early 1900 right when hydrocarbon use began to spike. This can be backed by looking at ice cores. Basically you go to the North Pole and drill out a giant pillar of ice. As the ice formed over the last thousand years or so it trapped bits of the atmosphere with it. We can just test different segments of the ice core to peer back at past atmospheres.
Paleoclimatology has multiple methods for testing past temperatures as well as the atmospheric condition. All of the test points towards the same conclusion. If you would like to know more about these test google the field they are fairly simple.
This is a cool gif graphing average temperatures for the past 150 years http://m.imgur.com/Rjdlzjz?r. As you can see things start to accelerate more recently.
Can someone please debunk these rebuttals: 1) Atmospheric temperature comes before CO2 levels
2) how do we not know that temperature increase is taking place on a geological timescale after the last glacial period?
3) why is data manipulated? Eg. Greenland harbour levels have been rising for quite a while but they only show a graph over the last 50 years. If it is set in stone then why are such schemes like this needed to be implemented?
This is not me declaring my climate change denial, but the only rebuttals from the other side that ive thought have been convincing.
- Accountants give us a meticulous accounting of the carbon we emit (because we buy and sell all our fuel. E.g. no-one gets gasoline for free, money changes hands, revenues are recorded. There is no possibility that ten times less fuel is sold than we think)
- map-makers (and many others) give us an exact knowledge of the size of planet Earth and the volume of the atmosphere (the globe is mapped very accurately; there is zero possibility that the earth is actually ten times bigger than we think it is, no possibility that the atmosphere has ten times more volume than we think it does).
- chemical equations give us a meticulous understanding of how much CO2 must result from the energy we get from fuel (and we know from accountants how much fuel we are using)
- direct measurement gives us a meticulous understanding of how much of the atmosphere is made up of CO2. Compared to that amount, we know that the amount of CO2 that we are adding to the atmosphere is so large that it significantly increases the amount of CO2 in the atmosphere
- physics gives us a meticulous understanding of the thermal properties of CO2 (so we know about things like the greenhouse effect)
The proof of climate change is that none of these things (accounting, maths, chemistry, physics) have enough margin for error or uncertainty on this subject for there not to be a big problem.
The exact bigness and speed of the big problem is debated, but there is no chance that it isn’t a BIG problem – the math just can’t add up any other ways.
(Simplified for ELI5. E.g. Ignoring things like ocean acidification, tipping points, methane warming, etc)
To get climate change, you need to know about foxes and rabbits. Otherwise the proof doesn’t make sense. (Stick with the story. It’ll make sense in the end.)
Imagine a grassland with foxes and rabbits. The foxes only survive on the rabbits. And the rabbits only worry about the foxes.
If the number of rabbits grows, the rabbits become easy prey. The foxes catch them. They get their fill. With all that easy food, the number of foxes grows fast.
The rabbits don’t have enough of them to keep their numbers up. So the number of rabbits shrinks. With less rabbits, hiding is much easier — even with all the foxes. The foxes can’t find enough rabbits in time. Many die of hunger. The number of foxes begins to shrink. With less foxes, the rabbits can multiply again. Soon, the number of rabbits is back up again. And the whole cycle starts again. Too many rabbits; then too many foxes; then too many rabbits; and so on.
It’s kinda like a swing — back and forth. But this back and forth is hard for us to see. Sure we see the numbers of foxes and rabbits growing and shrinking. But we don’t see how their numbers affect each other. When we don’t see stuff like that, we don’t think what we do makes a difference.
Let’s imagine us doing something. We start feeding the foxes. They scare away birds. And that helps our crops. So we want more of them. The more foxes; the less birds; the better our crops.
We start to notice fewer and fewer rabbits. We don’t think much of it. After all we know the number of rabbits fell in the past. Eventually we find something better than foxes to scare away birds. So we stop feeding the foxes. At this point, way too many foxes are in the grassland. They’re able to find most of the rabbits. The rabbits have no place to hide. Too many foxes are there!
Unfortunately by this point, the foxes won’t die off fast enough. The rabbits can’t reproduce quick enough. The foxes find all the rabbits and eat them. Once the rabbits die off, the foxes die as well. The balance ends.
We’ve been feeding the foxes. In this case though it’s heat — and the food is CO2. The rabbits are the cold.
It’s through this lens you need to look at climate change. We didn’t cause the back and forth of cold and hot. We’re causing the slight imbalance. And most of us never learned about the foxes and rabbits. We don’t know about the balance. We only think immediate cause and immediate effect. We don’t see systems that get thrown out of wack with just a little push.
By the way, this predator-prey analogy is true. Science recognizes it. We also have good evidence climate is like that too. We’ve fed the foxes for too long. And we don’t seem to want to stop. When non-scientists realize it’s too hot, rebalancing the system will be beyond our control.
- C02 is a gas.
- C02 traps heat.
- The atmosphere contains C02.
- Add more C02.
- Atmosphere traps more heat.
- Climate change.
If you’ve got the time and the inclination, this video series by Potholer54 is quite well done:
It goes into a lot more detail than it would be possible to in a reddit comment, and yet keeps at a fairly accessible level.
The main factors in determining a planets climate are distance from its sun, angle at which the sunlight hits, amount of sunlight reflected back into space, and amount of sunlight absorbed by the planet and/or its atmosphere.
Change any of these factors and the result will be climate change. We have seasons because the angle at which sunlight hits is more direct during summer and more indirect during winter. Climate change based on carbon dioxide levels works because it 1) increases the amount of sunlight absorbed or trapped within our atmosphere and 2) may cause a positive feedback loop of a warmer planet melting the polar ice caps which currently reflect a lot of sunlight back into space.
- Human activity (factories cars etc) releases gases like carbon dioxide into the atmosphere
- When sunlight hits earth, the changed atmosphere is more capable of holding onto heat energy that would otherwise be lost into space, aka “the greenhouse effect.”
- The warmer atmosphere (even if it’s only by one or two degrees on average) mean changes in weather patterns
- The warmer atmosphere also means more of the ice at the poles melts, potentially raising the sea level and putting currently-by-the-beach stuff underwater.
If you added a scoop of sugar to your lemonade, would it taste different? Of course. If you don’t put in the right grade of oil into your car, would it run right? No.
People understand that adding even tiny portions of chemicals into a system can change the way it works. Now, each year since 1990, the United States has released more than 5 billion metrics tons of carbon dioxide into the air. Keep in mind this is just the emissions of ONE greenhouse gas by ONE country in ONE year. If you think of the earth as a system, it just makes rational sense that adding such a huge amount of chemicals into our atmospheric system would have some sort of effect.
I’m going to come at this from a simple, indisputable facts of physics approach.
There are two things that make carbon dioxide a greenhouse gas.
- It is denser than oxygen or nitrogen (the main components of our atmosphere). Adding more carbon dioxide to the atmosphere increases the density of the atmosphere. If something is denser, it packs more mass into a given space and has a higher energy potential – if you shoot a ball of mattress foam out of a cannon, it’s going to do a lot less damage than a cannonball, because the foam has less mass and a lower energy potential. A denser atmosphere can hold more energy (get hotter and move faster), period.
- Carbon dioxide absorbs infrared light. Most of the light from the sun passes through the atmosphere without getting absorbed, that’s why the air is “clear”. Carbon dioxide, however, absorbs infrared light. So instead of reflecting it, like oxygen or nitrogen would, it absorbs it and gets hotter. This is the same principle that makes a black car in bright sunlight hotter to the touch than a white car – the black paint absorbs more of the energy from the light than the white paint. More carbon dioxide means the atmosphere absorbs more energy from the sun, rather than passing it through harmlessly and reflecting it back into space.
So carbon dioxide both makes it possible for the atmosphere hold more energy and get hotter, and makes the atmosphere absorb more energy from the sun. More carbon dioxide makes both of these effects worse.
Now water vapor is an even worse greenhouse gas than carbon dioxide, because it’s a lot denser and absorbs more of the light from the sun. But the amount of water that can be in the atmosphere is limited by the temperature. If it’s colder, the air can hold less water, if it’s warmer, the air can hold more water. This is why it tends to be dry in the winter and more humid in the summer. So if there’s more carbon dioxide in the atmosphere, not only can the temperature go up from that on its own, but it also makes it so the atmosphere can hold more water all the time.
Hydrocarbons (oil) are relatively stable molecules that have a lot of hydrogen and carbon in them. Before humans came along, they pretty much just sat underground doing not much of anything. When you burn hydrocarbons, they break down and combine with oxygen to produce carbon monoxide, carbon dioxide, carbon, and water. There’s a natural carbon cycle that has been going on for millions of years, but we’re specifically digging up hydrocarbons and using them to release carbon dioxide into the air.