Another system that is incredibly complex in terms of a lot of moving bodies is a liquid. One cubic centimetre of water (the size of a sugar cube?) will have on the order of 100 000 000 000 000 000 000 000 molecules in it, crashing into each other billions of times every second.
And yet single-molecule condensed phase spectroscopy has been a thing for at least 20 years: https://doi.org/10.1146/annure.... Heck, people can make movies of individual chemical reactions happening at the femtosecond timescale!
M.P. Minitti, J.M. Budarz, A. Kirrander, J.S. Robinson, D. Ratner, T.J. Lane, D. Zhu, J.M. Glownia, M. Kozina, H.T. Lemke, M. Sikorski, Y. Feng, S. Nelson, K. Saita, B. Stankus, T. Northey, J.B. Hastings, and P.M. Weber. Phys. Rev. Lett. 114, 255501 – Published 22 June 2015
I am not saying that M87 is similar to a box of water in terms of the challenges it presents. But I am saying that the combined amount of human knowledge surrounding some of these problems can make complex things doable.
I have seen children taught anywhere from five to seven continents, based on the country I have been in. I think there is a good chance only two continents exist: America and Europeasiafrica, based on the definition of "a large landmass completely surrounded by natural water". Antarctica possibly (14 million square km), and maybe you could make an argument for Australia (7.7 million). So let's be generous and say four continents.
A better question may be, why do people care about the definition of a continent? What purpose does it serve to label something as a "continent"? Is a continent a geographical feature (like I imply above) or a political classification? That would help create a more useful definition.
Thank you! This has always been my issue with companies that say, "Customers are our highest priority." I am pretty sure that staying in business is any company's highest priority.
I browse continuously at -1. I rarely find reasonable and intelligent posts there which go against cliches. And I see plenty of both cliche and non-cliche posts at higher levels. I do not doubt that some anti-cliche posts do get buried, but I also would need more evidence to believe that it happens on a wide scale.
Of course, I generally read stories a day or two late, when people are no longer moderating or commenting. Maybe comments that go against the cliches are buried quickly and then unburied by the time I make it to them.
I agree that nature is big and complex. I also agree that it's a bit silly to assign any specific event to climate change, and I do wish people would stop doing it.
What do we know? We know that the global mean temperature has risen by a degree recently (observations and analysis, including models and experiments). From all the evidence we have, the rate of this change is unprecedented. It corresponds very well with increasing emissions of certain gases, and we have a physical explanation for why these gases trap heat.
To predict the future, we need models. Decades of development on complex Earth system models has not produced perfect results. For evidence of that, look at future projections of terrestrial carbon. Look at climate projections for specific regions in the year 2100, in particular precipitation. The agreement between the models used in the IPCC reports is not great for both of these areas.
But all the models agree that increasing greenhouse gas emissions will continue to increase the global mean temperature.
Humans are changing the climate. With the impact that the land surface has on the atmosphere, and the fact that over half of the Earth's land surface has changed from its natural state as a result of human activities (primarily food production, including both crops and pasture for livestock), we should not be surprised that this is possible. What we don't yet know is exactly what the effects will be.
Do you know why it's there? The Founding Fathers were paranoid about monarchs, or anything that smelled like a monarch. For example, a political dynasty.
Back in the days, the only real way to become well-known at a young age and across the country was by being the son of a politician. The Founding Fathers put the age limit in to give others a chance to catch up through their actions, in order to prevent dynastic families. It made a lot of sense at the time, given their situation and their experiences with monarchs. It doesn't prevent dynasties completely, but it does change how they occur. John Quincy Adams was elected president 24 years after his father's term, but John Quincy also had a pretty solid career in foreign policy beforehand.
I am curious as to if a 25-year-old wildly-popular musician, actor/actress, or sports star would stand a chance of getting elected nowadays if an amendment was passed to eliminate the age qualification.
+1 for reference to CSM. Perhaps not perfect, but better than alternatives I've found.
I also like how they don't try to be a 24/7 news service. They publish a few in-depth articles a day, and they are happy to wait a couple days before publishing in order to have a more well-written story that contextualizes the discussion.
I am beginning to suspect that checking the news every minute leads to more intolerance of other viewpoints.
Even if it appeared to be random to most viewers, to me it suggests that he saw something other people didn't. Which probably makes him a genius (or insane). And since he was able to communicate that people outside his own mind, I would call him an artist of the highest order.
I doubt I could distinguish his works from a computer programmed to do the same thing. I can't tell the difference between a hyperrealist painting and a photograph, either, but I would much rather have a hyperrealist painting on my wall. For me, the method of production is integral to the artwork.
I feel like a major problem to this is your comment: "1000 breeding pairs of humans".
Right now, the technology to sustain a lifeboat on Mars is supported by...I am not sure how many people, but the supply chains are complex. Mining, manufacturing, transport, R&D, maintenance. Is it reasonable to expect two thousand people could maintain and create the tech, in addition to everything else they would be required to do (food, medicine)? If you never lived in the tropics and seen how quickly things break down there, it feels plausible, but we are literally talking about another world. Less humidity and salt in the air, sure, but more extreme temperatures and nasty solar radiation. Not to mention dust. How long until woman start routinely dying in childbirth because the medical equipment no longer works? All these "third-world" problems that our tech has eliminated will come back once the tech begins to fail.
I am all for space exploration, but I think we have a ways to go before we demonstrate the feasibility of a self-sustaining Mars base.
In my mind, that's the key: universities don't teach how to do research.
Universities teach how to use a number of tools found in research through coursework at both the graduate and undergraduate level. But that's very different than teaching how to do research. Even working on a semester-long or year-long research project as an undergraduate is very different than what an independent researcher will see. More importantly, how you approach the problem is very different as well.
Research is writing grant proposals. Research is designing experiments. Research is using cutting-edge tools published by groups of other scientists who probably made mistakes in the single paper documenting the tool and the results.
Universities give you a problem that is solvable, with high probability that the tool you need to solve it can be found in the preceding chapter (or chapters). I have yet to see research do that.
While I agree knowing the ten most common mistakes would be very useful, they mean very little to someone who has not yet already done research. As such, I expect a single class teaching them would have little impact.
If, on the other hand, you are proposing to redesign the whole curriculum and teaching methods to eliminate those mistakes, I think that might have a chance of being successful. On the other hand, given the amount of work that would take, you'd have to have very ambitious deans, department heads, and teaching faculty to make it happen.
I get your argument, and I agree with it, but I would caution against saying that CO2 doesn't absorb IR. It does, due to internal vibrational motion (stretches and bends); just look at the absorption spectrum.
It doesn't permanently absorb the light, though, and I think that's where what you say is critical. It absorbs it for a short time, and then the vibrational excitation drops back down to the lower state. When this happens, it emits a photon of the same frequency that it absorbed. This photon flies off in a random direction, creating the scattering effect.
At least, this is my understanding of it. Absorption happens in this scattering, but the timescale of absorption is very short.
If you left the comment on the feed of a journalist who said that about the miners, I might laugh at that; "just desserts" can be rewarding, as we see time and again in movies.
If you left that comment on the feed of a journalist who never said that, I think that's being a jerk. It's a mistake to hold person A responsible for the actions of person B when person A had nothing to do with it, even if they share the same label.
And if you were a coal miner who got fired, saw that reporter B made a comment about learning to code, then got fired...and you offered sympathy to reporter B instead of throwing their words back at them? You would have my admiration and respect. Okay, might not mean much if you're unemployed, but tweeting "Learn to code" at someone isn't going to help your employment status, anyway.
Maybe we should ditch the 24/7 news cycle, too. Where does this need for breaking news come from, anyway? Very, very few stories suffer for being held back for a couple days or a week to confirm facts, or to spend time putting the story in context.
I agree with the need the distinguish between the scientific method and "Science", and I would argue that scientific literacy is just as much about understanding the scientific method and applying it broadly as it as about knowing a collection of scientific facts.
That being said, what alternative to psychology do you propose? I will not argue that psychology has ruined lives. I am sure other fields (including the harder sciences) have similar dark spots on their records. Starting from the premise that given a lack of evidence all possibilities must be considered equally probable, new sciences use observations to make hypotheses. These hypotheses represent the best use of available evidence. They may be wrong, but they tip the scales towards certain possibilities, i.e., they increase our confidence that a given outcome is true.
People often discount the results of studies due to flaws in the study design or execution. These flaws are valid critiques, and they certainly need to be addressed in future work. However, if you do not present evidence showing that these flaws significantly impact the results, our original premise above says it is equally likely that the flaws do not impact the results. Therefore, what justification is there for ignoring the results? No study is perfect (I have yet to read a paper in chemistry or physics which is above reproach, including all the ones I've written), but I feel that disciplines closer to everyday life experience much more frequently this situation.
This may be the difference between science and religions. Science says that if everyone follows the scientific method, humanity will eventually arrive at the truth. It does not say that the current scientific understanding of the world is the truth, or that any individual living today will ever know truth. This distinction is vital, and perhaps not emphasised enough, likely due to the type of people mentioned in the previous paragraph who use criticism as a way to ignore results that they don't like, as opposed to accepting results they don't like as being the current "best guess" while using valid criticism to dig deeper in the future.
To quote Chief Justice Marshall from Foster v. Neilson in 1829: “In the United States, a different principle is established. Our constitution declares a treaty to be the law of the land. It is, consequently, to be regarded in courts of justice as equivalent to an act of the legislature, whenever it operates of itself, without the aid of any legislative provision. But when the terms of the stipulation import a contract—when either of the parties engages to perform a particular act, the treaty addresses itself to the political, not the judicial department; and the legislature must execute the contract, before it can become a rule for the court.”
If a treaty is "equivalent to an act of the legislature" (or even requires legislature to execute!), and acts of legislature are subject to the Constitution, how can a treaty supersede the Constitution? I would be curious if you have more modern case law which overturns this (I know the Court evolved a lot during the first 50 years or so).
Even assuming this is true for the moment, I'm not going to pretend it will be the case forever. I know enough talented Chinese researchers who are doing good work, and I see enough papers in high-quality journals with all-Chinese author lists, to see the shift coming. Either we play together, or we risk losing.
Fine, and one can say that about any field. Teachers? The good ones are the ones with a passion for teaching. Scientists? The best ones are those with a passion for learning. You don't need to recruit those because they will naturally find their field.
But what if you need 100 programmers/teachers/scientists, and you only have 10 who are passionate about it? Your task (as a society) is to fill the remaining 90 positions with people who can do the work. Which requires attracting people whose first instinct (and possibly passion) is a different field. That doesn't necessarily imply they can't be good programmers/teachers/scientists, but they may need nudging to realize this.
I am genuinely interested if you have an article to share on this. I spent a lot of time last year looking at peer-reviewed scientific literature studying the effect of nutrition on illness prevention and cure, and I don't remember seeing anything about vitamin D and the flu (either for or against). So I didn't even realize this was a thing.
This is something I've noticed, too. If I go for a while (even only a few days!) without free sugars, all desserts taste incredible. If I've been eating non-fruit desserts and snacks fairly regularly, I'm often disappointed by things like simple cakes and cookies and prefer denser, more concentrated desserts like cookie dough and brownies.
I was thinking about this a couple months ago and did a double-blind taste test with my girlfriend (Mexican coke in a glass bottle vs. American coke in a plastic bottle). Neither one of us identified one as tasting better than the other.
I am not sure that is true. Young forests might (ignoring any carbon release from soil or decomposing biomass that disturbed the previous forest on the site, but of which should not be ignored), but an individual old tree will consume a lot more carbon than an individual young tree. Stephenson et al published a nice paper in Nature about that back in 2014.
From the authors: "Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree."
The observational evidence we have collected shows the global temperature reached one degree Celsius above pre-industrial levels in 2017 (the difference between the global mean surface temperature from 1850-1900 and 1987-2017...Figure 1.2 from the recently released IPCC special report "Global Warming of 1.5 C"). Previous studies have found solar activity and volcanic eruptions to be of minimal impact, in particular over the past few decades.
Atmospheric carbon dioxide concentrations, on the other hand, have been increasingly steadily since pre-industrial times. Scientists, being sceptical by nature, are quick to point out to each other that correlation does not equal causation. Through the use of increasingly sophisticated methods and models, they are now reasonably sure that carbon dioxide is one of the primary drivers (though methane and nitrous oxide are not something to forget about). Incidently, these models include water vapor, but water vapor doesn't explain the temperature increase, so no, I would not consider that a pollutant.
Carbon dioxide, at the concentrations we are currently seeing it, does seem to be negatively (for us) impacting the environment. So yes, despite that it is necessarily for life on this planet, I would start calling it a pollutant. "Good for you" and "bad for you" is often a matter of concentration.
Slashdot Mirror
This analogy might prove interesting to you.
Another system that is incredibly complex in terms of a lot of moving bodies is a liquid. One cubic centimetre of water (the size of a sugar cube?) will have on the order of 100 000 000 000 000 000 000 000 molecules in it, crashing into each other billions of times every second.
And yet single-molecule condensed phase spectroscopy has been a thing for at least 20 years: https://doi.org/10.1146/annure.... Heck, people can make movies of individual chemical reactions happening at the femtosecond timescale!
M.P. Minitti, J.M. Budarz, A. Kirrander, J.S. Robinson, D. Ratner, T.J. Lane, D. Zhu, J.M. Glownia, M. Kozina, H.T. Lemke, M. Sikorski, Y. Feng, S. Nelson, K. Saita, B. Stankus, T. Northey, J.B. Hastings, and P.M. Weber. Phys. Rev. Lett. 114, 255501 – Published 22 June 2015
I am not saying that M87 is similar to a box of water in terms of the challenges it presents. But I am saying that the combined amount of human knowledge surrounding some of these problems can make complex things doable.
What's the definition of a continent?
I have seen children taught anywhere from five to seven continents, based on the country I have been in. I think there is a good chance only two continents exist: America and Europeasiafrica, based on the definition of "a large landmass completely surrounded by natural water". Antarctica possibly (14 million square km), and maybe you could make an argument for Australia (7.7 million). So let's be generous and say four continents.
A better question may be, why do people care about the definition of a continent? What purpose does it serve to label something as a "continent"? Is a continent a geographical feature (like I imply above) or a political classification? That would help create a more useful definition.
Thank you! This has always been my issue with companies that say, "Customers are our highest priority." I am pretty sure that staying in business is any company's highest priority.
I browse continuously at -1. I rarely find reasonable and intelligent posts there which go against cliches. And I see plenty of both cliche and non-cliche posts at higher levels. I do not doubt that some anti-cliche posts do get buried, but I also would need more evidence to believe that it happens on a wide scale.
Of course, I generally read stories a day or two late, when people are no longer moderating or commenting. Maybe comments that go against the cliches are buried quickly and then unburied by the time I make it to them.
I agree that nature is big and complex. I also agree that it's a bit silly to assign any specific event to climate change, and I do wish people would stop doing it.
What do we know? We know that the global mean temperature has risen by a degree recently (observations and analysis, including models and experiments). From all the evidence we have, the rate of this change is unprecedented. It corresponds very well with increasing emissions of certain gases, and we have a physical explanation for why these gases trap heat.
To predict the future, we need models. Decades of development on complex Earth system models has not produced perfect results. For evidence of that, look at future projections of terrestrial carbon. Look at climate projections for specific regions in the year 2100, in particular precipitation. The agreement between the models used in the IPCC reports is not great for both of these areas.
But all the models agree that increasing greenhouse gas emissions will continue to increase the global mean temperature.
Humans are changing the climate. With the impact that the land surface has on the atmosphere, and the fact that over half of the Earth's land surface has changed from its natural state as a result of human activities (primarily food production, including both crops and pasture for livestock), we should not be surprised that this is possible. What we don't yet know is exactly what the effects will be.
Do you know why it's there? The Founding Fathers were paranoid about monarchs, or anything that smelled like a monarch. For example, a political dynasty.
Back in the days, the only real way to become well-known at a young age and across the country was by being the son of a politician. The Founding Fathers put the age limit in to give others a chance to catch up through their actions, in order to prevent dynastic families. It made a lot of sense at the time, given their situation and their experiences with monarchs. It doesn't prevent dynasties completely, but it does change how they occur. John Quincy Adams was elected president 24 years after his father's term, but John Quincy also had a pretty solid career in foreign policy beforehand.
I am curious as to if a 25-year-old wildly-popular musician, actor/actress, or sports star would stand a chance of getting elected nowadays if an amendment was passed to eliminate the age qualification.
+1 for reference to CSM. Perhaps not perfect, but better than alternatives I've found.
I also like how they don't try to be a 24/7 news service. They publish a few in-depth articles a day, and they are happy to wait a couple days before publishing in order to have a more well-written story that contextualizes the discussion.
I am beginning to suspect that checking the news every minute leads to more intolerance of other viewpoints.
I agree that Pollock's work was semi-random, not completely random.
From a 1999 article in Nature, Pollock's work had a fractal dimension that increased steadily during his life.
Even if it appeared to be random to most viewers, to me it suggests that he saw something other people didn't. Which probably makes him a genius (or insane). And since he was able to communicate that people outside his own mind, I would call him an artist of the highest order.
I doubt I could distinguish his works from a computer programmed to do the same thing. I can't tell the difference between a hyperrealist painting and a photograph, either, but I would much rather have a hyperrealist painting on my wall. For me, the method of production is integral to the artwork.
I feel like a major problem to this is your comment: "1000 breeding pairs of humans".
Right now, the technology to sustain a lifeboat on Mars is supported by...I am not sure how many people, but the supply chains are complex. Mining, manufacturing, transport, R&D, maintenance. Is it reasonable to expect two thousand people could maintain and create the tech, in addition to everything else they would be required to do (food, medicine)? If you never lived in the tropics and seen how quickly things break down there, it feels plausible, but we are literally talking about another world. Less humidity and salt in the air, sure, but more extreme temperatures and nasty solar radiation. Not to mention dust. How long until woman start routinely dying in childbirth because the medical equipment no longer works? All these "third-world" problems that our tech has eliminated will come back once the tech begins to fail.
I am all for space exploration, but I think we have a ways to go before we demonstrate the feasibility of a self-sustaining Mars base.
In my mind, that's the key: universities don't teach how to do research.
Universities teach how to use a number of tools found in research through coursework at both the graduate and undergraduate level. But that's very different than teaching how to do research. Even working on a semester-long or year-long research project as an undergraduate is very different than what an independent researcher will see. More importantly, how you approach the problem is very different as well.
Research is writing grant proposals. Research is designing experiments. Research is using cutting-edge tools published by groups of other scientists who probably made mistakes in the single paper documenting the tool and the results.
Universities give you a problem that is solvable, with high probability that the tool you need to solve it can be found in the preceding chapter (or chapters). I have yet to see research do that.
While I agree knowing the ten most common mistakes would be very useful, they mean very little to someone who has not yet already done research. As such, I expect a single class teaching them would have little impact.
If, on the other hand, you are proposing to redesign the whole curriculum and teaching methods to eliminate those mistakes, I think that might have a chance of being successful. On the other hand, given the amount of work that would take, you'd have to have very ambitious deans, department heads, and teaching faculty to make it happen.
I would say Finland, as well. I've heard many a Finn complain about how difficult it is to get good rye bread outside of Finland.
Then again, perhaps diets have changed. This is just based on my experience.
Well, of course dung beetles are in deep crap! They would be in a lot more trouble if they weren't in deep crap.
I get your argument, and I agree with it, but I would caution against saying that CO2 doesn't absorb IR. It does, due to internal vibrational motion (stretches and bends); just look at the absorption spectrum.
It doesn't permanently absorb the light, though, and I think that's where what you say is critical. It absorbs it for a short time, and then the vibrational excitation drops back down to the lower state. When this happens, it emits a photon of the same frequency that it absorbed. This photon flies off in a random direction, creating the scattering effect.
At least, this is my understanding of it. Absorption happens in this scattering, but the timescale of absorption is very short.
If you left the comment on the feed of a journalist who said that about the miners, I might laugh at that; "just desserts" can be rewarding, as we see time and again in movies.
If you left that comment on the feed of a journalist who never said that, I think that's being a jerk. It's a mistake to hold person A responsible for the actions of person B when person A had nothing to do with it, even if they share the same label.
And if you were a coal miner who got fired, saw that reporter B made a comment about learning to code, then got fired...and you offered sympathy to reporter B instead of throwing their words back at them? You would have my admiration and respect. Okay, might not mean much if you're unemployed, but tweeting "Learn to code" at someone isn't going to help your employment status, anyway.
I gave up on Skype a while ago and moved to Jitsi. Accessible through the web, free, open source. Don't even need an account to start a call.
Makes me wonder how they stay afloat. I hope they are not recording my calls!
Maybe we should ditch the 24/7 news cycle, too. Where does this need for breaking news come from, anyway? Very, very few stories suffer for being held back for a couple days or a week to confirm facts, or to spend time putting the story in context.
I agree with the need the distinguish between the scientific method and "Science", and I would argue that scientific literacy is just as much about understanding the scientific method and applying it broadly as it as about knowing a collection of scientific facts.
That being said, what alternative to psychology do you propose? I will not argue that psychology has ruined lives. I am sure other fields (including the harder sciences) have similar dark spots on their records. Starting from the premise that given a lack of evidence all possibilities must be considered equally probable, new sciences use observations to make hypotheses. These hypotheses represent the best use of available evidence. They may be wrong, but they tip the scales towards certain possibilities, i.e., they increase our confidence that a given outcome is true.
People often discount the results of studies due to flaws in the study design or execution. These flaws are valid critiques, and they certainly need to be addressed in future work. However, if you do not present evidence showing that these flaws significantly impact the results, our original premise above says it is equally likely that the flaws do not impact the results. Therefore, what justification is there for ignoring the results? No study is perfect (I have yet to read a paper in chemistry or physics which is above reproach, including all the ones I've written), but I feel that disciplines closer to everyday life experience much more frequently this situation.
This may be the difference between science and religions. Science says that if everyone follows the scientific method, humanity will eventually arrive at the truth. It does not say that the current scientific understanding of the world is the truth, or that any individual living today will ever know truth. This distinction is vital, and perhaps not emphasised enough, likely due to the type of people mentioned in the previous paragraph who use criticism as a way to ignore results that they don't like, as opposed to accepting results they don't like as being the current "best guess" while using valid criticism to dig deeper in the future.
Wait, what? When did that happen?
To quote Chief Justice Marshall from Foster v. Neilson in 1829: “In the United States, a different principle is established. Our constitution declares a treaty to be the law of the land. It is, consequently, to be regarded in courts of justice as equivalent to an act of the legislature, whenever it operates of itself, without the aid of any legislative provision. But when the terms of the stipulation import a contract—when either of the parties engages to perform a particular act, the treaty addresses itself to the political, not the judicial department; and the legislature must execute the contract, before it can become a rule for the court.”
If a treaty is "equivalent to an act of the legislature" (or even requires legislature to execute!), and acts of legislature are subject to the Constitution, how can a treaty supersede the Constitution? I would be curious if you have more modern case law which overturns this (I know the Court evolved a lot during the first 50 years or so).
Even assuming this is true for the moment, I'm not going to pretend it will be the case forever. I know enough talented Chinese researchers who are doing good work, and I see enough papers in high-quality journals with all-Chinese author lists, to see the shift coming. Either we play together, or we risk losing.
Fine, and one can say that about any field. Teachers? The good ones are the ones with a passion for teaching. Scientists? The best ones are those with a passion for learning. You don't need to recruit those because they will naturally find their field.
But what if you need 100 programmers/teachers/scientists, and you only have 10 who are passionate about it? Your task (as a society) is to fill the remaining 90 positions with people who can do the work. Which requires attracting people whose first instinct (and possibly passion) is a different field. That doesn't necessarily imply they can't be good programmers/teachers/scientists, but they may need nudging to realize this.
I am genuinely interested if you have an article to share on this. I spent a lot of time last year looking at peer-reviewed scientific literature studying the effect of nutrition on illness prevention and cure, and I don't remember seeing anything about vitamin D and the flu (either for or against). So I didn't even realize this was a thing.
This is something I've noticed, too. If I go for a while (even only a few days!) without free sugars, all desserts taste incredible. If I've been eating non-fruit desserts and snacks fairly regularly, I'm often disappointed by things like simple cakes and cookies and prefer denser, more concentrated desserts like cookie dough and brownies.
I was thinking about this a couple months ago and did a double-blind taste test with my girlfriend (Mexican coke in a glass bottle vs. American coke in a plastic bottle). Neither one of us identified one as tasting better than the other.
YMMV.
I am not sure that is true. Young forests might (ignoring any carbon release from soil or decomposing biomass that disturbed the previous forest on the site, but of which should not be ignored), but an individual old tree will consume a lot more carbon than an individual young tree. Stephenson et al published a nice paper in Nature about that back in 2014.
From the authors: "Thus, large, old trees do not act simply as senescent carbon reservoirs but actively fix large amounts of carbon compared to smaller trees; at the extreme, a single big tree can add the same amount of carbon to the forest within a year as is contained in an entire mid-sized tree."
The observational evidence we have collected shows the global temperature reached one degree Celsius above pre-industrial levels in 2017 (the difference between the global mean surface temperature from 1850-1900 and 1987-2017...Figure 1.2 from the recently released IPCC special report "Global Warming of 1.5 C"). Previous studies have found solar activity and volcanic eruptions to be of minimal impact, in particular over the past few decades.
Atmospheric carbon dioxide concentrations, on the other hand, have been increasingly steadily since pre-industrial times. Scientists, being sceptical by nature, are quick to point out to each other that correlation does not equal causation. Through the use of increasingly sophisticated methods and models, they are now reasonably sure that carbon dioxide is one of the primary drivers (though methane and nitrous oxide are not something to forget about). Incidently, these models include water vapor, but water vapor doesn't explain the temperature increase, so no, I would not consider that a pollutant.
Carbon dioxide, at the concentrations we are currently seeing it, does seem to be negatively (for us) impacting the environment. So yes, despite that it is necessarily for life on this planet, I would start calling it a pollutant. "Good for you" and "bad for you" is often a matter of concentration.