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The whole thing with Mercury was readily visible and had been observed for a long time, but Newton and others never came up with an acceptable explanation for i

The whole thing with Mercury was readily visible and had been observed for a long time, but Newton and others never came up with an acceptable explanation for it while Einstein did. This didn't involve insane precision or high speeds or anything like that. (I guess the Sun counts as a pretty large mass, though.) And the basic rules of Newtonian gravity have been repeatedly questioned lately (beyond Einstein's revisions), but I don't know if any of that has stuck. > Warmer air can hold more water vapor. Yes indeed it can, and said water vapor (being a greenhouse gas) can induce more greenhouse gas effects. But this appears to be routinely glossed over, as if it's just a non-issue; not everyone agrees with that assessment, though. As to the warmer air thing, lots of people make statements to the effect that warmer air holding more water vapor will lead to much heavier rainfall and such. Which certainly MIGHT be true, but it doesn't HAVE to be true. Why? Because there's nothing that says that all of that additional water vapor has to fall out of the sky in one fell swoop; a lot of it may just stick around as higher humidity. Plus it is well-known that rain sometimes falls from the clouds only to evaporate again in the warmer, drier air underneath those clouds, so it never actually makes it to the ground, and generally warmer air may lead to more of that. You almost never hear these facts mentioned, though. Funny story: Some years back I was listening to a science podcast where a climatologist and an oceanographer were guests, and the subject of sea and air temperatures came up. The climatologist made a statement about "warming temperatures leads to more storms" and such, but the oceanographer corrected him, saying that while that used to be the thinking, further research had shown that if sea and air temperatures would changing more or less in tandem (both warming up together, in this case), then surprisingly the overall effect on storms actually appeared to be pretty inconsequential. And I thought the climatologist was going to blow a gasket over this; I mean, how DARE the oceanographer go "off message" like that!

kaybe 8y ago
> Yes indeed it can, and said water vapor (being a greenhouse gas) can induce more greenhouse gas effects. But this appears to be routinely glossed over, as if it's just a non-issue; not everyone agrees with that assessment, though. You mean as in the models don't include it? I'm very sure they do, I'd have to search for citation though. > As to the warmer air thing, lots of people make statements to the effect that warmer air holding more water vapor will lead to much heavier rainfall and such. Which certainly MIGHT be true, but it doesn't HAVE to be true. That's why we use models to try and figure out what the probable truth is. This part is hard though, and only 'medium confidence' is reached for any influence on the water cycle since 1960 at all. (https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_TS_FINAL.pdf https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_TS_FINA...) I wouldn't rely too much on those precipitations change forecasts yet either, but things will change if we keep going like this. > Funny story: .. Haha, I can imagine. The storm thing is complex and hard to predict too. Let me cite the IPCC report: 'Confidence remains low for long-term (centennial) changes in tropical cyclone activity, after accounting for past changes in observing capabilities. However, for the years since the 1970s, it is virtually certain that the frequency and intensity of storms in the North Atlantic have increased although the reasons for this increase are debated (see TFE.9). There is low confidence of large-scale trends in storminess over the last century and there is still insufficient evidence to determine whether robust trends exist in small-scale severe weather events such as hail or thunderstorms.' Table 11 here has details on the model runs: https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter11_FINAL.pdf https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter... Looks like your oceanographer was right. But I guess your point was the attitude, not the facts. There seems to be a general problem in communication since the beginning. Concluding, what's your general point? Do you think that CO2 is not a problem? Do you want to doubt the specific predictions? (The IPCC reports helps to differentiate between virtually certain and still doubtful points, they're not all the same.) Do you want to critize the attitude in communication? (I do think these issues need to be communicated and discussed better. Also, at this point it's really in the hands of politicians and society to work with this, not scientists.) Addendum: There is vivid discussion of the water issue here: https://www.skepticalscience.com/water-vapor-greenhouse-gas.htm https://www.skepticalscience.com/water-vapor-greenhouse-gas....
- southern_cross 8y ago
  I don't have time for a long detailed reply but I will respond to a couple of things here. > Do you think that CO2 is not a problem? It's not so much that I think "that CO2 is not a problem", but rather that it's probably not THE problem when it comes to climate change issues - and certainly not the most pressing problem of our age, as it is often made out to be. And I think people who go too far down that path ("We're all doomed!") are maybe a little off-kilter mentally, to put it nicely, but there seems to be quite a few of them out there. As to skepticalscience.com, some years back I spent many an hour reading through the stuff there, but eventually got to the point where I just no longer took it too seriously. The page you pointed me to "has issues"; the entire web site itself "has issues"; and even the guy who runs the site (John Cook) "has issues". I won't go into the details here because if you are as familiar with the situation as I am then I'm sure you're aware of at least some of those issues.
  - kaybe 8y ago
    What do you think our most pressing problems are? And what to you think the problem is when it comes to climate change issues? I'm interested in your opinions and ideas since you seem to have given this a lot of thought.
    - southern_cross 8y ago
      Coal is a problem, end-to-end. The buildup of nuclear waste (at least in the U.S.) is a problem. Sufficient freshwater supplies are a problem. Wildfires are a problem. Pollution (particularly plastics) is a problem. Concentrated overpopulation (too many people crammed into too small a space) is a problem. "Refugeeism" is a problem (note that I didn't say "refugees".) The threat of nuclear war (or at least the threat of rogue nations and such) is still a potential problem. And so on. But what really disturbs me on a longterm basis is the fact that we have so much of our population and infrastructure located along coastlines. We've built permanent infrastructure on largely impermanent land, which is often perpetually at risk. And I'm not just talking about sea level rise, but rather subsidence (the land is often sinking faster than the sea is rising), constant erosion, hurricanes (common and often devastating), tsunamis (less common but often even more devastating), and so on. As to sea level rise itself, the seas have been rising pretty incessantly ever since the start of the last interglacial period (if I'm using the right terminology here), and AFAIK there is nothing to indicate that this has ever stopped. It has apparently proceeded in fits and starts, though, and by my math it's still occurring at something like half the rate of the historical average. So when some mentions sea level rise in relation to climate change my reaction is more like "So what? Sea level rise is nothing new, but it's less of aa overall global issue now than it was in the past. As for any anthropogenic influences, that's more a matter of rate than anything. But unless the natural part of sea level rise comes to a complete stop, then all of that coastal infrastructure is pretty much doomed in the long run anyway, and it's probably not even particularly safe even if it does stop."
yongjik 8y ago
> The whole thing with Mercury was readily visible and had been observed for a long time, but Newton and others never came up with an acceptable explanation for it while Einstein did. This didn't involve insane precision or high speeds or anything like that. https://en.wikipedia.org/wiki/Tests_of_general_relativity https://en.wikipedia.org/wiki/Tests_of_general_relativity Perihelion of Mercury was observed to advance by 574 seconds per century. That is 0.16 degree per century, or 0.0016 degree per year. Of this 574 seconds, Newtonian physics could accurately explain 532 seconds as gravitational interactions between planets. That still leaves about 42 seconds as unexplained. General relativity predicts an additional 43 seconds, which is a near perfect match. Of course, it's always a matter of opinion whether something is "insane precision"... so feel free to think it is not. (Never mind most people never see Mercury itself in their lifetime: I certainly haven't.)

kaybe 8y ago

> Yes indeed it can, and said water vapor (being a greenhouse gas) can induce more greenhouse gas effects. But this appears to be routinely glossed over, as if it's just a non-issue; not everyone agrees with that assessment, though. You mean as in the models don't include it? I'm very sure they do, I'd have to search for citation though. > As to the warmer air thing, lots of people make statements to the effect that warmer air holding more water vapor will lead to much heavier rainfall and such. Which certainly MIGHT be true, but it doesn't HAVE to be true. That's why we use models to try and figure out what the probable truth is. This part is hard though, and only 'medium confidence' is reached for any influence on the water cycle since 1960 at all. (https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_TS_FINAL.pdf https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_TS_FINA...) I wouldn't rely too much on those precipitations change forecasts yet either, but things will change if we keep going like this. > Funny story: .. Haha, I can imagine. The storm thing is complex and hard to predict too. Let me cite the IPCC report: 'Confidence remains low for long-term (centennial) changes in tropical cyclone activity, after accounting for past changes in observing capabilities. However, for the years since the 1970s, it is virtually certain that the frequency and intensity of storms in the North Atlantic have increased although the reasons for this increase are debated (see TFE.9). There is low confidence of large-scale trends in storminess over the last century and there is still insufficient evidence to determine whether robust trends exist in small-scale severe weather events such as hail or thunderstorms.' Table 11 here has details on the model runs: https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter11_FINAL.pdf https://ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter... Looks like your oceanographer was right. But I guess your point was the attitude, not the facts. There seems to be a general problem in communication since the beginning. Concluding, what's your general point? Do you think that CO2 is not a problem? Do you want to doubt the specific predictions? (The IPCC reports helps to differentiate between virtually certain and still doubtful points, they're not all the same.) Do you want to critize the attitude in communication? (I do think these issues need to be communicated and discussed better. Also, at this point it's really in the hands of politicians and society to work with this, not scientists.) Addendum: There is vivid discussion of the water issue here: https://www.skepticalscience.com/water-vapor-greenhouse-gas.htm https://www.skepticalscience.com/water-vapor-greenhouse-gas....

southern_cross 8y ago
I don't have time for a long detailed reply but I will respond to a couple of things here. > Do you think that CO2 is not a problem? It's not so much that I think "that CO2 is not a problem", but rather that it's probably not THE problem when it comes to climate change issues - and certainly not the most pressing problem of our age, as it is often made out to be. And I think people who go too far down that path ("We're all doomed!") are maybe a little off-kilter mentally, to put it nicely, but there seems to be quite a few of them out there. As to skepticalscience.com, some years back I spent many an hour reading through the stuff there, but eventually got to the point where I just no longer took it too seriously. The page you pointed me to "has issues"; the entire web site itself "has issues"; and even the guy who runs the site (John Cook) "has issues". I won't go into the details here because if you are as familiar with the situation as I am then I'm sure you're aware of at least some of those issues.
- kaybe 8y ago
  What do you think our most pressing problems are? And what to you think the problem is when it comes to climate change issues? I'm interested in your opinions and ideas since you seem to have given this a lot of thought.
  - southern_cross 8y ago
    Coal is a problem, end-to-end. The buildup of nuclear waste (at least in the U.S.) is a problem. Sufficient freshwater supplies are a problem. Wildfires are a problem. Pollution (particularly plastics) is a problem. Concentrated overpopulation (too many people crammed into too small a space) is a problem. "Refugeeism" is a problem (note that I didn't say "refugees".) The threat of nuclear war (or at least the threat of rogue nations and such) is still a potential problem. And so on. But what really disturbs me on a longterm basis is the fact that we have so much of our population and infrastructure located along coastlines. We've built permanent infrastructure on largely impermanent land, which is often perpetually at risk. And I'm not just talking about sea level rise, but rather subsidence (the land is often sinking faster than the sea is rising), constant erosion, hurricanes (common and often devastating), tsunamis (less common but often even more devastating), and so on. As to sea level rise itself, the seas have been rising pretty incessantly ever since the start of the last interglacial period (if I'm using the right terminology here), and AFAIK there is nothing to indicate that this has ever stopped. It has apparently proceeded in fits and starts, though, and by my math it's still occurring at something like half the rate of the historical average. So when some mentions sea level rise in relation to climate change my reaction is more like "So what? Sea level rise is nothing new, but it's less of aa overall global issue now than it was in the past. As for any anthropogenic influences, that's more a matter of rate than anything. But unless the natural part of sea level rise comes to a complete stop, then all of that coastal infrastructure is pretty much doomed in the long run anyway, and it's probably not even particularly safe even if it does stop."

yongjik 8y ago

> The whole thing with Mercury was readily visible and had been observed for a long time, but Newton and others never came up with an acceptable explanation for it while Einstein did. This didn't involve insane precision or high speeds or anything like that. https://en.wikipedia.org/wiki/Tests_of_general_relativity https://en.wikipedia.org/wiki/Tests_of_general_relativity Perihelion of Mercury was observed to advance by 574 seconds per century. That is 0.16 degree per century, or 0.0016 degree per year. Of this 574 seconds, Newtonian physics could accurately explain 532 seconds as gravitational interactions between planets. That still leaves about 42 seconds as unexplained. General relativity predicts an additional 43 seconds, which is a near perfect match. Of course, it's always a matter of opinion whether something is "insane precision"... so feel free to think it is not. (Never mind most people never see Mercury itself in their lifetime: I certainly haven't.)