How Climate Change /Actually/ Works...in 4 Minutes
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- Опубліковано 22 сер 2024
- I totally get and agree with the instinct to simplify by saying "It's like a greenhouse" or "a heat-trapping blanket" but, like, what's actually going on?
It's not that complicated! More energy is coming in than is going out because of WIGGLES.
And yes, I'm talking about this because it feels like maybe MAYBE the US will have a climate bill that will actually, measurably reduce emissions on a fairly tight time scale which is massive.
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One important missing bit here: The solid bits of Earth absorb the visible light, and heat up (why it warms way up during the day). They then radiate that heat out in the IR (why everything cools down at night), which is absorbed by the carbon dioxide, methane, water vapor in the air instead of escaping out to space. That's where the more energy in than out comes from. The Earth is wearing a blanket, and we keep adding more and more blankets.
I felt like, despite the fact that that is among the most important mechanisms of climate change, it would be confusing. People don't think of the earth as emitting light, so I'd have to get into that.
So I think I understand but correct me if I'm wrong. Is this why, on a really hot (& especially dry) day, you can often feel *more* heat coming from the ground than hitting you on the top of the head?
@@vlogbrothers That's fair. 4 minutes is a very short time for a radiative transfer lecture :)
Maybe "could JWST see the earth?" would be a cool future topic, looking at the wavelengths JWST can see vs. those emitted by the earth. If not for VlogBrothers, then maybe SciShow Space?
Black body radiation, right?
@@shortourt14 yes, that's exactly it! When you feel heat coming off of something, you're sensing the infrared radiation. There's a lot less atmosphere between you and a parking lot than between you and space. A lot of the IR from the sun gets absorbed or scattered before it gets to you, but you're basically feeling every bit of IR coming off the parking lot.
I just did a quick experiment and pointed an IR thermometer at my patio and then at the bluest patch of sky I could find. The thermometer can tell the temp by the intensity of infrared it can see. My patio is sitting at 106°F (41°C). The air temp is 79°F (26°C). The sky reads 8°F (-13°C). So there's a lot less infrared (heat) coming from above you than from below. The whole reason the sun feels hot is the absorption Hank mentioned in his video. Unfortunately I can't get a reading pointed at the sun itself because it's too cloudy today. If I get one though I'll add another comment.
I’m consistently impressed by how well you can explain complex topics clearly in such short time
Well, he’s had over 14 years to practice!
go see crash course
Totally agree! I just rewatched his video he did years ago back when the Webb telescope was launched (I think) and he was explaining how we look back in the past with the space photography.
That's Hank's superpower 💪
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I totally agree. I hadn’t appreciated in such simple terms why these gasses would cause heating. What a brilliant skill to capitulate something so accessibly.
It happens in 4 minutes? That's scary
Thats what i was comin to say xD No wonder its such a big problem
and this is why we comma
I think it takes a bit longer than that, Hank.
The good news is it only takes 10 minutes to change it back again....🙃
If only, scientifically literate people agreeing something exists was enough for something to politically _exist._
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Or even if they consent to agree that it exist, stop pretending that it can be solve by individual efforts instead of a collective one.
We need a pro-science party in the US with a reasonable climate policy.
@@Billchu13 Andrew Yang is starting a 3rd party... they will be announcing the other people in the group at the end of this week (or next week not entirely sure)
Its gonna be a pro-science party and will be announcing their platform at the same time as they qnouce the other candidates and famous people who are part of the party.
It's called the "forward party" their jingle is "not left or right, we need to move forward"
Most of the time whatever it is that exists goes directly against capitalism.
Profit seeking. At all costs.
"I'm getting all this money from huge oil companies, my life is great. Why should I care about an issue that will make me loose money but gain nothing out of" - is what the usual case is for people in power in this system we all live in.
The black t shirt metaphor for climate change is the first metaphor that has allowed me to fully and completely grasp the concept of what’s going on.
I was quite happy when I stumbled across it. I don't think I would have thought about it if I hadn't spent so much time thinking about IR light because of the JWST!
@@vlogbrothers A note: the black t-shirt metaphor doesn't really work, in that black makes you cooler unless you're standing in completely still air and are stationary yourself. This is because your body is actually a far greater source of infrared radiation than the sun is in relation to the surface area of your shirt. So, while it absorbs the sun's heat, it also absorbs yours. With a light breeze, that heat will be carried away faster; a white shirt, on the other hand, will reflect the infrared light directly back at your skin, trapping the heat. This is especially true since the infrared light trapped by greenhouse gases has been re-emitted by the Earth at lower energies than when it reached us; hence how it gets trapped (it'd be strange if our atmosphere was somehow unidirectional). So it's far more like a white t-shirt than black.
However, the metaphor is still useful because the black clothing misconception is so common that we can at least use it like we do the Bohr model of the atom.
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@@darthtace But, wait, the sun hits the ground with 1,370 watts of energy per square meter. A person puts out nowhere near that much energy. How is it possible that your body is a greater source of IR on a shirt sized area than the sun is?
The numbers I found for total human energy output (not even just the IR portion): 100w at rest, 2-400w comfortably, 2000w for an Olympic athlete at peak sprint. Source: a Stanford article that YT ate the link to, but it's the first search result for "human body energy release."
What I want to know is: what the hell could you have possibly thought was going on if a shitty metaphor made you think you "fully and completely grasp the concept of what’s going on."
"absorb, reflect, or let pass through/ that's basically the only three things material can do"
please include this in a new science-y song. it just flows so well
Came here to say the same thing 😂
Actually had to rewind to see if it had actually been a poem all along that I'd missed 😂
Melodysheep for the win!!
I also came here to say the same thing! It had quarks vibes
Sounds like a good line for a SciShow Tangents traditional science poem!
I’m doing my PhD in physical chemistry and I love hearing you communicate science - it helps me set my barometer of which details are generally understandable and which are not.
Do I have a lot of brain crack about science communication? Yes why do you ask 😬
It's good that you're mindful about communicating science, it's a skill many should get better at (coming from an engineer working with science communication).
At the very least, it gives you a framework of communicating with science communicators!
Try explaining it to a drunk person at a (quiet) party. Alas I'm a curious lightweight so I'm an excellent litmus test for Does That Make Sense?
@@embolobolo4237 The same people who do not know what a woman is, want to imprison people for war crimes for not agreeing with the climate change religion
A PhD is no guarantee you cannot be wrong, mistaken or just full of s***.
Great explanation!
Sometimes I think the four minute limit is too restrictive, but it can help make really concise, informative videos.
This video for sure counts as educational and is exempt from the time limit.
That's the plan!
@@BFedie518 i think it’s super useful to have these short explanations, like u could send this to someone and they’d be more likely to watch the whole thing
The shorter the video, the greater the chance people will watch to the end.
I tend to avoid very long videos.
I think we as a species are very good at solving problems given two things:
1) we agree that it's a problem
2) we agree that it's worth solving
I think we spend so much of our energy focusing on the minority of people who don't think that its real we end up completely ignoring the quiet majority of people who believe that it's inevitable and therefore not worth the effort to solve.
But I feel like the people in the second group often simply don't understand how bad of a problem it really is, making them more like the first group. Like, it's not all people who are just living in despair; it's also those dumb people who say it's fine if it gets a little hotter because we can just run our air conditioners more, completely missing the scope of the problem and the fact that it's not just that it might be a little hotter outside sometimes.
Agreed! In the US, it seems to me like 1) is a larger issue than here in Sweden, but here I feel like we are struggling with 2) and getting nowhere or even going backwards. Not many solutions seem to be considered worth it either politically or economically by the people with power, even though almost all agree on climate change = really bad.
There are also some who know it's real, know it's avoidable, and don't care because continuing to exacerbate the problem is profitable.
I think this is right on the money, though I think it is strawmanning the second position a little bit.
First, I think there is reasonable disagreement and uncertainty over what the "it" is that is inevitable. Is climate change an extinction-level catastrophe or just really bad (though of course with the burdens falling disproportionately on nation's that don't have the power or population to make a dent in global emissions)? The answer to that affects the cost-benefit calculus.
Second are reasonable disagreements over the geographical scope of claims of justice. What do sovereign nations owe one another? Is it important that people can continue to be tied to their ancestral lands? Important enough to prioritize over the same industrialization that has led to vast increases in life expectancies (and not just in wealthy nations)? These are hard questions and while the answer almost certainly isn't to do nothing, positions that fall short of sweeping societal change look reasonable with small tweaks to any of the answers. We get nowhere when we fail to engage in good faith with the reasons motivating those across the political divide. I appreciate that OP's comment starts to do that!
reflexive impotence
My molecules don't jiggle jiggle, they...turn light into kinetic energy?
"Absorb, reflect, or let pass through:
Those are the things a material can do"
Gonna use this to teach my kids how light works lol.
Objects interacting with light can also emit light which happened to be omit-ted in this video (sorry for the pun!)
2:01 I feel the explanation works better if you say "transfers its jiggle" rather than its heat. The jiggle is what causes what we perceive as heat after all, and it makes so much more intuitive sense that a jiggling object hittin another object that jiggles less is likely to cause the second object to jiggle more.
'Wiggles' should become standard terminology for climate scientists.
All scientists...everything is wiggles.
@@vlogbrothers Butt may or may not be legs, but at least we can all agree that they're both just lots of wiggles.
Scientists need to stop with the Good Vibrations and get on the wiggle train!
Also, i cant stop thinking of "my money don't jiggle jiggle, it folds" from this video
String Theorists have entered the chat
@@dukeofburgerz5225 My molecules don't jiggle jiggle, they cold
I just called my senators to urge them to vote for the Inflation Reduction Act (that includes many climate provisions) and I was freaking out about the phone calls but I did it!!! Ahhhhh
Climate change is such an important issue. I've only been seriously concerned about it since 2018 or so, and I can't imagine how frustrated people like you, Hank, who have been involved in the climate fight for so long, must be with all of the governmental inaction. Your videos on climate change help me to feel more hopeful for the future. Thank you.
way to go!! I totally get freaking out abt the phone calls, I’ve been doing stuff like that long enough that it shouldn’t be hard but it still is. but it’s so important so good for you! celebrate that win!!
I'm in Kentucky. 0% chance my senator will support it. I call though. So at least he had one more thing he had to listen and then ignore between being the worst.
Ahahahaha money printing causes inflation, lets print more money to solve inflation. And you want me to trust commies to solve climate change 🤣🤣🤣🤣🤣
you should be ashamed of yourself for being such an uneducated, gullible fool
Great video!
Alas, one small correction: there is a major difference between convection and conduction. Conduction, which occurs in all states of matter, is when how molecules hit colder ones, thus transferring energy. In convection, the hot molecules move themselves towards colder areas. This can happen only manily when molecules can move enough, thus only in fluids which are not too viscous, and is aided by gravit, as hot fluids are generally less dense.
pausing my Dear Hank And John binge to watch a vlogbrothers video
As an ex-aspiring-particle-physicist, this was the most fun explanation of climate change to listen to that I’ve encountered so far.
Also yes I too am still not over the idea that heat comes from being jiggly in a way we can’t feel directly.
Those were excellent references for reflecting specific wavelengths of light. I reread Pratchett regularly, just blindly grab one and read it all the way through.
I am so excited to see a Sir Terry Pratchett book in your hands! Excellent choice too. And thanks for discussing this difficult topic.
GNU Sir Terry
@@pintpullinggeek GNU ❤
the turtle moves! Gnu STP
Climate scientist here. That was excellent.
I was about to comment that I was embarrassed that it literally took til this video for me to actually understand even the broadest strokes of what is happening with climate change, but I’m going to reframe it. I’m grateful you took the time to explain it concisely and simply for folks like me who have been in support of fighting climate change but have been left a bit behind in being taught the specifics.
Same. 100%
so before this video, you had political views on climate change, but after watching this video, you realize you didn't even understand the topic. how does that make you feel?
As an ecologist I appreciate you talking about this Hank!
Small correction: When you are not in direct sunlight radiation still forms a very significant part of the heat you feel. In fact, in building physics it's often said that 55% of your subjective warmth experience indoors comes from radiation from walls, floor and ceiling, and only 45% from convection/conduction. A wood floor feels warmer, not because it looks that way but because it literally radiates more heat to you. Remember that every object in the universe is constantly radiating heat.
Me myself I love my limited edition corvette Z06 C7 Racing Edition, but last year I drove it on average 4 days a week. Now I drive it only once a week and ride my bike. Now let’s imagine everyone cut their driving by 75% WOW what a huge difference that would make, immediately. We need to make a change and make it now.
We can end like 2/3s of our emissions just by living in walkable cities. Nobody needs a car if you build your city the way humans have built cities for 5000 years. And rowhouses and apartments can be heated and cooled for a miniscule fraction of a suburban McMansion. It would also make everyone's lives cheaper (in direct car costs and in local taxes for infrastructure) and healthier (in exercise benefits from walking and mental/social benefits of actually seeing your neighbors).
I hope you guys do an explainer on urbanism someday! Until then, people should check out Not Just Bikes :)
You are 1000% correct.
But the things you suggested won't make the already wealthy (who are heavily invested in the industries who created those fossil fuel intensive messes) slightly richer.
Therefore your ideas are communism and must be purged from freedumb™ loving America.
my thoughts at the start of this video: "yeah, I've listened to/read/watched a lot of stuff about climate change, I know this probably won't be new info but I'll watch it anyway because I care and it's a good reminder :("
my thoughts at the end of this video: OH MY GOD, THAT IS *LITERALLY* HOW IT HAPPENS. WHY HAS NO ONE EVER EXPLAINED THIS TO ME
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SAME
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That was a lot to digest in under 4 minutes... I _almost_ agree that we can solve any problem as long as we agree that it exists... the caveat is that we also have to prioritize that problem... that seems to be the issue this particular problem faces. Super glad to hear that there are people who understand the problem though!
Billionaires pay millionaires to tell me that climate change is just a communist plot of liberal Islam to take away my guns and freedumb™.
it's not prioritized b/c it's bs issue
"absorb, reflect, or let pass through...
the only three things a material can do"
that'd make a fine song lyric.
I like your color sample book choices
its really just ever so frustrating that the start of this fight begins at convincing others that it.. exists
I feel like it is actually an easy problem that's made difficult because of selfishness. All of the problems we have can be overcome, and humans have shown an ability to solve problems for thousands of years. The big issue is that these problems are difficult because people have a vested interest in them not being overcome.
So I feel that saying it isn't an "easy" problem can be used as an excuse to further the position of those people who want to keep things in the status quo, because they'll claim that "it's difficult and will take time", when it wouldn't take nearly as much time if they weren't literally putting their foot down on the break and refusing to let anyone within 50 feet of the pedal.
It would take a huge amount of restructuring in my community, in my country, to stop adding CO2 and methane to the atmosphere. To the point where it will cost billions of dollars and in order to do it quickly enough a complete overhaul of our transportation, shipping, agriculture, and basically ever industry.
I think you are right to an extend, the problem is further complicated by the selfishness of those who profit from prolonging the death throws of fossil fuels, but I also don't want to downplay the complicated nature of how to completely change power grids globally. Or completely change how we ship goods globally.
Someone of the issues we absolutely have a solution that would be workable if the powers that be would just buckle down and do, but some of the issues we're dealing with we do not have a workable solution for right now.
anyone who holds up a discworld book has my support tbh
This was not what I expected, but really good and compact explanation.
Recently I was at school and found an old TIME magazine from 2006. The cover article was about the tipping point for climate change, and most of the contents were explaining what climate change is and how it works so people can agree that it exists… I hope it’s not too late for things to change
We're going to be in a live wet bulb experiment here by next Wednesday.
wait wtf why did I not learn that CO2 and Methane are black in the infrared spectrum? I have a god damn bachelors degree in environmental science
Now I’m going to be constantly thinking about how the molecules around me are jiggle jiggling
Thank you for explaining it in 4 minutes and saying that it exists
My problem with using the word “greenhouse” is that I went into a greenhouse for the first time LAST YEAR. Like most people don’t even know how greenhouses work
Well you see, greenhouses work a lot like our atmosphere, only instead of using CO2 of CH4 to trap in the heat, it uses glass. /s
And they're not even green! They're like a whitish gray color
@@chris-hayes Green houses aren't even green? I feel so lied to.
@@chris-hayes A greenhouse is not a green house, it is a house for green things 😁
@@wakjagner was it made of 0.04 % glass?
I like to think of myself as well educated on climate change and it’s causes but I don’t think I really understood it until now. That is absolutely the best explanation of climate change I have ever seen, heard, or read. Thanks Hank.
"Absorb, reflect, or let pass through: that's basically the only thing a material can do" sounds like the start of a song haha!
My money don't jiggle jiggle, but my molecules do.
It would be interesting with a discussion of how we best can invest our efforts and resources to combat this problem, without unknowingly and accidentaly making the problem worse. Which arguments might be the result of different economic interests, and which possible solutions are good guesses as to the way forward? Can we alter the way things normally are and save more lives than cutting production of different foods? Specifically interested in the arguments of Bjorn Lomborg and the dangers of repeating Mao’s huge mistake. It seems to me agreeing on the portrayed solutions is a really important discussion to have, as there seems to be a slightly polarized debate. Underlining the knowledge behind the solutions is a way to combat that. I think you guys would be great at adressing these issues.
Thanks for a great video!
it's just so pathetic how you leftists think you're going to crash world economies and chase something you can't even prove; ie, controlling weather globally
"There's no way we're getting out of this, without a lot of really good ideas." -Hank Green, 2007
A really good idea is overthrowing the capitalist system plunging the world into climate hell to make a few already wealthy ghouls slightly richer.
I think it's fair to revise that to just "There's no way we're getting out of this."
Even the IPCC (as incredibly conservative as it is) has accepted and stated that climate change is abrupt and irreversible. What people still don't appreciate though is how bad "abrupt and irreversible" will be sooner rather than later for all of us.
SO after 14 years, what ideas have you come up with?
@@dnice4335 I often hear people talking about how inventive and adaptable humans are. But when it comes to climate change all of the inventiveness and adaptability seems to have been put into denying, ignoring, and downplaying it rather than prevention...
@@dnice4335 Seize the means of production from the Capitalist ghouls burning the world is a solid plan
Hi Hank. Regarding this replacement of energy needs with something that doesnt create CO2, can you PLEASE spread the word about the incredibleness of thorium reactors? We need more people talking about it and more money spent on it because this is a very logical, plausible, and important possible solution for coal burning energy production replacement.
What people don't seem to understand is it will get worse before it gets better. Humans have spent hundreds of years industrializing the planet (and thousands of years changing the planet before that) and it will take time to balance out our impacts. As we have adapted the world to are needs with cities, agriculture and infrastructure specialized species unable to cope with the changes we've made may go extinct and climate patterns with become more extreme and dangerous but eventually, with the effort of multiple generations, our environments will change to coexist with a natural world, generalist species will adapt and diversify, and we'll stabilize the climate.
Loved this guy from crash course. Finding this vlog was almost like meeting an old friend that tutored me in Junior College
I continue to be confounded by how many adults that have been around for several decades can look around and conclude that THIS is how things have always been, as if summers and winters were no different when they were younger. I know a several who are fully in denial that the climate is changing in any way, and I'll never understand how they can be so oblivious.
These are the same people who walked up hill 10 miles both ways to school. And to acknowledge the change would also admit responsibility for the collective selfishness / willful ignorance that led us here. That's not to say we'd have done better in their position, but it's easier to keep the illusion alive than to confront the terrifying and tragic reality. Plus, they'll be dead before the worst of it so why bother engaging? Plus, they're being exploited and manipulated by the 1% and mass media :'(
Yes, it is so glaringly obvious to me, having lived in roughly the same area my entire life. Winters rarely get cold anymore here.Spring is earlier and hotter. Summer extends far into what used to be the cool crisp days of fall. Even the insects are behaving differently. Loud night insects didn’t start their cacophony until August-it was like an insectoid calendar. Now they are starting in June. Those who are in denial have been brainwashed.
Why is Hank calling me John? Is my name John now? Ok, my name is John now
On vlogbrothers they make videos talking to each other. The other guy on the channel is John and will talk to Hank in his videos.
The melting of the ice caps is absorbing some of this heat (like an ice cube that keeps your glass of water at 0°C). Once all the ice is gone, the temperature increases will be more obvious.
People also don't seem to realize that the ice caps are a key part of the weather system and it will be very, very bad if they go away. The ice caps are the reason we have ocean currents.
that was a throw back episode to earlier VlogBrothers and was an Excellent explainer.
"If we can only get people to agree that they exist." *existential dread resumes*
🎶 My molecules don't jiggle jiggle, I'm cold. 🎵
happy friday! dftba
Dftba!
DFTBA!
I already understood climate change but particals being black in the infrared made it that much clearer. Thanks Hank!
3:39 Include Military Infrastructure to this list. Pound for pound, military industrial complexes induce massive CO2 output and have been notoriously slow to change to climate-friendly hardware. It's hard to replace fossil fuel for systems that rely on instant, explosive power at scale, and harder still because military superpowers include legacy hardware(check Russia's ancient Soviet-era tanks moving into Ukraine for example) as part of their total calculus for forces and total war scenarios. Militaries typically do not transition hardware right away because it diminishes combat ready firepower in the moment.
got those Richard Feynman vibes.
If only it was a knowledge gap that was the problem.
Just to nitpick: "Convection" is energy transfer because the hot thing moved to a new place before releasing its extra energy. That's why it generally happens in fluids, but it isn't just what we CALL energy transfer in a fluid. So if you were playing the game Hot Potato with a literal hot potato that you'd just taken from the oven, that would technically be considered burning your hands by convection even though you're tossing around a solid.
Convection refers to fluid flow caused by buoyancy when there are areas of different density in in fluid. Heat transfer between molecules in a fluid is still conduction.
Going Postal might be my favorite Discworld novel.
"absorb, reflect, or let pass through...that's basically the only three things that a material can do" bars
Thank you Hank, this is very important and I hope lots of people see it, but it's also making me think about the fact that I'm 22, and I remember being 10 or 12 and learning all of this, from school and from youtubers like you and the rest of the educational youtube-sphere, and it was obvious, settled science. The fact that in that time it feels like so many people either haven't learned it or are actively ignoring it is so disheartening, that we're still in the same place in regards to educating the public (and the politicians) as we were when I was 10, and I can vote now and I'm doing what I can but it doesn't feel like enough. But thank you for doing this as many times as you have to, for explaining it as many times as it needs to be explained for people to get it. Maybe nerdfightaria's next big project can even be something to do with the climate crisis! DFTBA
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Just a quick note: The atmosphere isn't heated directly by light coming from the sun. It's, in fact, heated by the ground (which itself is heated by the sun).
The following is a simplification, but the sun gives off mostly high energy light (visible, UV) which our atmosphere is transparent to. That high energy light makes it's way through the atmosphere on its way in, no problem, and reaches the ground.
The ground heats up and then the ground releases low energy light (infrared). Through the infrared that it radiates and conduction+convection, the ground heats up the atmosphere.
The amount by which the atmosphere is heated depends on how many GHGs are in it to absorb that low energy light given off by the ground, hence the greenhouse effect.
That's why the air gets colder as you go up in altitude.
Sorry for bothering, I've been studying environmental geography recently and was completely ruffled by finding out that the atmosphere heats up from the bottom.
"The atmosphere isn't heated directly by light coming from the sun". LOLOLOLOL. that must be why record high temperatures happen at 3am
@@RobertMJohnson But they do! In fact, nighttime near-surface temperatures are increasing _faster_ than daytime temperatures. Look it up. Sim Jans is absolutely right: this was the one thing that Hank got (slightly) wrong. Hank mentioned infrared light from the Sun, but this is emitted in much shorter wavelengths we call near infrared (range ~0.7 - 3.0 µm); this is _not_ the infrared light implicated in climate warming. That IR light is in the longer, "thermal" IR wavelengths (~8 - 20 µm) -- because it is "Earthlight", not sunlight (I'm using "light" as a stand-in for electromagnetic radiation" here, but it is accurate: all EMR can be considered "light"). The point that Sim Jans raised is an important one and I'd like to implore all science communicators to get it right -- since so many of 'em get this wrong.
I always thought it wasn't that CO2 absorbs more infrared light from the sun but instead it absorbs more radiation emitted from the Earth. Most of the light that hits the earth is either visible or UV light as the Sun emits those frequencies the most (see blackbody radiation). Most of the UV light is blocked by the atmosphere while visible light travels through (mostly) unaffected. The problem arises from the fact that the Earth emits light, and thus sheds its excess heat, in the infrared regime (for the same reason living beings light up on an infrared camera; objects ~50-100 deg F emit mostly infrared radiation). The CO2 in the atmosphere then absorbs this light and emits it in every direction, with ~50% being reflected back into the lower atmosphere and towards Earth's surface. So it's not that more heat is coming into the atmosphere but that less heat can escape. A bit nitpicky, I know, but just wanted to point that out
It does do both, but it's harder to grasp that CO2 in the atmosphere acts as both a black shirt for all the IR radiation from the Sun, but also as a mirror for the IR radiation coming from the Earth
@@dukeofburgerz5225 trouble is, it’s misleading because if it wasn’t there it would pass through to the earth anyway be absorbed and heat it up. Just not as much as the visible light which has more energy
The Earth emits just as much heat out to space as it ever did. That never changes. It can't be increased, though. Meanwhile, we're diminishing the albedo of the Earth while also creating a lot more heat with our activities. This heat doesn't amount to all that much, if we weren't putting so much CO2 into the atmosphere that sequesters that heat in the atmosphere. We have less and less plant cover to absorb CO2 and the oceans are nearly saturated with what they can absorb, so we're in dire straights now. The important thing is that as long as it took us to create this backlog of heat that needs to escape to space, it will take at least that long again for it to do so, even if we stop pouring any CO2 up there. If we stop dead now, the temperatures are going to continue to rise, and it will be about 300 to 1,000 years before CO2 comes back down to the present level of ~400ppm, let alone back to 280ppm. And none of this accounts for the effects of methane or feedback loops that will very quickly make things worse.
Yeah, It's a shame that it's confusing, but learning involves being confused. I don't think we do well to use inaccurate analogies, and just gloss over the totally wrong parts of the comparison.
Don't take it to seriously when someone says "this stuff was always so confusing to me, but you made it so much simpler. I GET it now!"
Makes me cringe every time.
0:30 keeping this in mind, are thermometers simply molecular speed guns?
12 years ago I took a 200 level atmospheric science class on climate change, and the main thing I remember taking away from it is that the class all agreed a better name for climate change is "drastic anthropogenic climate destabilization." You chemistry that idea up very nicely here, Hank, cheers!
you took a class? wow. i took a class on Jesus Christ as the son of God as your savior, too.
I’m glad Terry Pratchett made a cameo in this video. He would approve!
We can also pump our atmosphere full of more white molecules to reflect more energy coming in, and while we already know which molecules to use we still need to figure out whether and how to do it safely without causing even more problems than we are currently having.
I would like to put in a shameless plug for the How to Save a Planet podcast.
It's hopeful without sugarcoating things, imho. They often talk about possible solutions to changing the systems that contribute to climate change. There are also often calls to action. Honestly, it's one of my favorite things right now.
The issue isn't about blaming "scientifically illiterate" people, it's about an economic system that is controlled by a small elite, i.e. corporations, who aims for profit over everything else. Name the fundamental problem, capitalism.
When you brought up a “clear” shirt it made me think of that SpongeBob episode where he made a sweater out of his tears
Hank Green is holding up my very first discworld novel which means he probably has read it and I just 😭😭😭😭😭😭😭
My background is in chemical physics. One other thing worth mentioning: water vapor is by far the dominant greenhouse gas in the Earth's atmosphere (much more than methane or CO2). But how much water vapor the atmosphere can contain depends on temperature: higher temperature--increased greenhouse contribution from water vapor. It's a positive feedback loop that amplifies any change due to other greenhouse gases.
It's wild and disconcerting to think that people use cost as a prohibitive factor when it comes to fighting climate change. Like, "The concept of money and financial exchange, which is entirely a human construct, won't let us repair our damaged planet, without which we will all die."
Hank is my hero for holding up two books from two of my favorite authors!
I don't think our societies can solve this. Some of things you mentioned will be hard to replace completely, yeah. But even the easy stuff, like reducing animal agriculture and reducing our destruction of old-growth is met with violent opposition. We're done.
This was great, thank you! Would you also like to do a follow up on the best possible mitigation solutions and how to go about things? But this would also include discussing political questions due to considerations of consumption and decolonisation. Anyway thanks and also I didn't quite get how exactly increase in greenhouse gases would directly lead to increased precipitation and extreme weather events?
Crash course geography might help with the weather one. A hotter climate disrupts weather patterns. And that series should cover that.
Scishow should also have some climate videos and hopefully a playlist.
Going Postal is a great book. I just got into Terry Pratchett.
At the 3:30 mark of the video Hank is talking about the only way to stop it and he says "less co2 and methane" but the closed caption reads "more co2 and methane".
That is such a fantastic way to understand the problem...
Wow when I was first taught that global warming/climate change was actually happening and not something some people thought might be happening (in high school around 2009 in Florida) I remember they showed us graphs showing something to the effect of historical CO2 amounts and historical global temperatures and suggested that there was evidence the two were somehow related, and we should just be very concerned about the extreme increase in CO2. I was just willing to listen to scientific consensus, but I'm sort of in shock I had never seen an actual explanation of what greenhouse gases were doing, then or after.
Small correction at 2:08. Conduction AND convection occur in gasses. They are not the same thing with different names.
Why that one frame?
Well...sometimes you gotta just put in one frame of a piece of stock footage you decided not to use...totally intentionally...definitely 100% on purpose. Yep!
bahahah I slowed it way down to find what frame you were talking about and Hank are 0.25x speed sounds HAMMERED
The english CC has a mistake in it at 3:30: ".... to stop it is for there to be MORE co2 and methane"
It should read ".... to stop it is for there to be LESS co2 and methane"
I thought convection was when the heated matter moves itself, so it doesn't need to conduct heat to other matter to move heat from one place to another. Which happens more in fluids because fluids naturally move themselves around to transport heat when temperature differences cause density differences which cause buoyancy?
Not just "conduction but it's in a fluid instead of a solid". In a zero-g environment it seems like convection wouldn't happen (in a fluid) because the buoyancy requires gravity, but conduction and diffusion would still transfer heat through it, just less quickly than it would with convection.
0:25 And when you're cold, it means your molecules don't jiggle jiggle, they fold
In her work, "Thinking About Social Problems," Sociologist Donileen Loseke suggests that two things have to happen before people agree to solve a problem together: (1) understand it is a problem and (2) understand it is something that needs the attention of groups of people (not personal problem, but a social issue). That seems sort of obvious, but, in fact, a lot of debate is exactly on these two points. We either argue about whether it really is a problem or not. We also argue about whether it is social or not. Climate Change gets debated regarding #1 and things like healthcare and crime gets debated regarding #2. Objectively, there are ways to demonstrate both that there is a problem and that it needs to be addressed on a social level. Unfortunately, people react subjectively.
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Billionaires pay millionaires to tell me that social problem study actively ignores that power in our society sits in the hands of the billionaires that will burn the whole world if it makes them slightly richer.
... and as always, the power is yours!!
important video topic, but i just realized hank has returned to his former haircut, the Hank
This is obviously a fantastic video with brilliantly expressed and explained scientific literacy. But I also want you to know that because of the 4 minute video length. I use these videos as a timer when making super noodles.
So basically I benefit twice. Once with knowledge. Once with perfectly cooked noodles
love to see hank take any possible opportunity to plug discworld
I think your captions may be wrong, did you mean to say the only way to stop global warming is for there to be “more co2 and methane from the atmosphere”? I wasn’t sure what that meant. Thanks for the video, I thought it was well put and simple to understand!
What , digging up carbon that had been sequestered for tens of millions of years and releasing it back into the biosphere ? I can't think of a single thing that could go wrong ...
I think the only part missing is black body radiation and the general photon emission by practically everything, so the things jiggling more also create more radiative heat transfer.
On the flip side is the IR transmission window in our atmosphere that we should probably exploit more. Space is cold, let's give it our extra heat.
Was kinda hoping you'd explain CO2 absorption band saturation. People using this complication to discredit the simplified greenhouse effect analogy grinds my gears.
A brilliant summary, well done.
A blanket obeys Q = U A dT. 0.04% CO2's specific heat capacity plays an insignificant role.
The physical walls of a greenhouse closed systems stifles the kinetic convective processes rasing the required dT.
The atmos is an open system w/o physical walls. In case you had not noticed.
Couple important thing to add. Most of the sun's energy reaches earth as visible light, not IR (which is why it's not blocked by the same greenhouse gasses). About 51% of the visible light is absorbed by ground, vegetation and water and some percentage of that is then radiated back toward the sky in the IR wavelengths, which is what keeps the earth's surface from just continuing to heat up.
And the greenhouses gases don't just absorb the IR energy, and heat up the atmosphere forever. They re-radiate it in all directions, some percentage of which comes back toward the earth which is what is responsible for the net increase in warming of the surface.
Think of the greenhouse gases as more like a semi-transparent mirror of IR energy.
And of course "Greenhouse" is a misnomer because real greenhouses created a physical barrier between warmer air inside and cooler air outside. Greenhouse glass does also absorb and re-radiate IR energy like greenhouse gases, but the overall the physical barrier is more important. It would be more accurate to call them something like "blanket gasses" where a blanket can be porous (like an afghan) letting air through but still provide a warming effect by absorbing and re-radiating some of the IR energy back inward.
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Hey Hank! Absolutely love the video, though the subtitles at 3:29 say 'more' instead of 'less'. Just letting you know :)
I’ve never heard it described this way. You’re always interesting Hank