4 ms·

As usual, ChuckMcM steps in as the voice of complete reason. I have no doubts that we are undergoing climate change, however, since when have we NOT undergone

by kjackson2012 14y ago

As usual, ChuckMcM steps in as the voice of complete reason. I have no doubts that we are undergoing climate change, however, since when have we NOT undergone climate change? We have had catastrophic ice ages and the Medieval Warming Period, when the Earth was warmer than it is now. All without the help of man-made "greenhouse gases". We know that extreme climate changes have occurred in the PAST, and we know that extreme climate changes will occur in the FUTURE. What makes THIS particular climate change so different and more significant from the previous ones? Just because we happen to be alive for this one? A theory that only answers one particular observation but can't explain other observations doesn't feel particularly valuable to me.

scarmig 14y ago
I'm curious: why do you put "greenhouse gases" in scare marks? It's rather unclear what your goal is besides emotive outburst. Are you denying that the greenhouse effect exists? That chemicals exist that interact with various forms of EM radiation? That those chemicals can exist in a gaseous state? Maybe you're skeptical that they're man-made. If so, why not put the quotes around "man-made" instead of "greenhouse gases"?
- spikels 14y ago
  Might be because the climate does not operate like a greenhouse. A greenhouse works by physically preventing convection from carrying away warm air. Greenhouse gases work by absorbing and reemmitting radiation that would otherwise escape into space. Both result in warming but completely different mechanisms. Unfortunately we are stuck with this misleading terminology in what is an already complex and politically charged area.
snowwrestler 14y ago
Yes, we care because we are alive right now. Knowing that ocean levels were even higher 60 million years ago is cold comfort to billions of poor coastal dwellers today.
- ChuckMcM 14y ago
  This is a common retort, "Oh it was millions of years ago, not 'now'" Consider that our ancestors were fighting for survival in the midst of an ice age. Sure, its "pre-written-history" but it isn't "pre-human-history".
  - snowwrestler 14y ago
    Retort to what? I honestly don't understand what point you're trying to make here.
    - ChuckMcM 14y ago
      Your right, insufficient context, my apologies. There is a common set of exchanges that occur in climate discussions that go like this: Person A: "Here is climate change without humans" (person A in this context is trying to argue that change will occur because there are other sources of change) Person B: "That was millions of years ago" (person B in this context is often trying to argue that what ever caused climate change 'back then', doesn't apply to current change) Neither person directly addresses the emotional argument/fear, and neither person tries to establish a common frame of reference. In context, kjackson2012 was making the 'things change' argument and your (snowrestler) response about the 'cold comfort' was in the context of the emotional argument. It is kind of like an exchange that goes "Oh we ordered too much food for the party." followed by "That's cold comfort to Ethiopians who are starving." On its face it seems like an argument that had we ordered less party food, there would be more food for Ethiopians. And yet the link between this party's food budget and that country's food problems is tenuous at best and generally a non sequitur. The point I was trying to make was that responding to the comment about change with a statement about timelines is a common one in climate discussions. Had I not reflexively responded to what I see as a common fallacy in the debate, I might have more constructively asked this: Given that coastal dwellers are now aware that the sea level will change, possibly significantly, for their great grandchildren. And that we know that there is nothing known to science today or predicted by our models that can stop it, how do you suggest we comfort these coastal dwellers of the present?
elemenohpee 14y ago
> Just because we happen to be alive for this one? Uh, yeah, that'd be it. What with all the massive extinction events and all, it might be in our interest to minimize the effects.
3am 14y ago
"What makes THIS particular climate change so different and more significant from the previous ones?" The speed at which it's occurring and it's correlation with man-made CO2 emission levels.
anigbrowl 14y ago
Medieval Warming Period, when the Earth was warmer than it is now. Not actually true, and in any case a much more gradual warming over a longer timescale; it's well summarized at http://en.wikipedia.org/wiki/Medieval_Warming_Period http://en.wikipedia.org/wiki/Medieval_Warming_Period I can't help being struck by the contrast between climate skeptic's loud insistence on greater scientific rigor in discussions of the present climate, and their hand-waving invocations of the MWP as a general-purpose tool of dismissal. I mean, all you need to do is look at a graph of the temperature data to see how different the rate of change is between the MWP and today.
- zosima 14y ago
  It is worth noting that method for producing the data 1900-2010 data and the 0-1900 data in the top graph is wildly different. First and foremost: The black line is an actual temperature measurement, while all the other lines are estimates based on proxies. Except of course: Secondly all the proxies appears to be correlated to the black line, because they have been chosen to do so. That is, the correlation to the black line is manufactured, and not a finding. The rest of the graph is made in a completely different manner, and the proxies are allowed to carry the signal for themselves. I think it is very interesting that you can see a small medieval warming period from the proxy data, but nevertheless one shouldn't be too eager to compare the right part and the left part of the graph, as the methods used are actually not the same. One can also show that the noise in the proxies will tend to pull the data towards the average and away from the extremes, which is exactly the lower rate of change and lower peaks you see. So that graph is really not very good, at all...
- deleted 14y ago
  [deleted]

scarmig 14y ago

I'm curious: why do you put "greenhouse gases" in scare marks? It's rather unclear what your goal is besides emotive outburst. Are you denying that the greenhouse effect exists? That chemicals exist that interact with various forms of EM radiation? That those chemicals can exist in a gaseous state? Maybe you're skeptical that they're man-made. If so, why not put the quotes around "man-made" instead of "greenhouse gases"?

spikels 14y ago
Might be because the climate does not operate like a greenhouse. A greenhouse works by physically preventing convection from carrying away warm air. Greenhouse gases work by absorbing and reemmitting radiation that would otherwise escape into space. Both result in warming but completely different mechanisms. Unfortunately we are stuck with this misleading terminology in what is an already complex and politically charged area.

snowwrestler 14y ago

Yes, we care because we are alive right now. Knowing that ocean levels were even higher 60 million years ago is cold comfort to billions of poor coastal dwellers today.

ChuckMcM 14y ago
This is a common retort, "Oh it was millions of years ago, not 'now'" Consider that our ancestors were fighting for survival in the midst of an ice age. Sure, its "pre-written-history" but it isn't "pre-human-history".
- snowwrestler 14y ago
  Retort to what? I honestly don't understand what point you're trying to make here.
  - ChuckMcM 14y ago
    Your right, insufficient context, my apologies. There is a common set of exchanges that occur in climate discussions that go like this: Person A: "Here is climate change without humans" (person A in this context is trying to argue that change will occur because there are other sources of change) Person B: "That was millions of years ago" (person B in this context is often trying to argue that what ever caused climate change 'back then', doesn't apply to current change) Neither person directly addresses the emotional argument/fear, and neither person tries to establish a common frame of reference. In context, kjackson2012 was making the 'things change' argument and your (snowrestler) response about the 'cold comfort' was in the context of the emotional argument. It is kind of like an exchange that goes "Oh we ordered too much food for the party." followed by "That's cold comfort to Ethiopians who are starving." On its face it seems like an argument that had we ordered less party food, there would be more food for Ethiopians. And yet the link between this party's food budget and that country's food problems is tenuous at best and generally a non sequitur. The point I was trying to make was that responding to the comment about change with a statement about timelines is a common one in climate discussions. Had I not reflexively responded to what I see as a common fallacy in the debate, I might have more constructively asked this: Given that coastal dwellers are now aware that the sea level will change, possibly significantly, for their great grandchildren. And that we know that there is nothing known to science today or predicted by our models that can stop it, how do you suggest we comfort these coastal dwellers of the present?

elemenohpee 14y ago

> Just because we happen to be alive for this one? Uh, yeah, that'd be it. What with all the massive extinction events and all, it might be in our interest to minimize the effects.

3am 14y ago

"What makes THIS particular climate change so different and more significant from the previous ones?" The speed at which it's occurring and it's correlation with man-made CO2 emission levels.

anigbrowl 14y ago

Medieval Warming Period, when the Earth was warmer than it is now. Not actually true, and in any case a much more gradual warming over a longer timescale; it's well summarized at http://en.wikipedia.org/wiki/Medieval_Warming_Period http://en.wikipedia.org/wiki/Medieval_Warming_Period I can't help being struck by the contrast between climate skeptic's loud insistence on greater scientific rigor in discussions of the present climate, and their hand-waving invocations of the MWP as a general-purpose tool of dismissal. I mean, all you need to do is look at a graph of the temperature data to see how different the rate of change is between the MWP and today.

zosima 14y ago
It is worth noting that method for producing the data 1900-2010 data and the 0-1900 data in the top graph is wildly different. First and foremost: The black line is an actual temperature measurement, while all the other lines are estimates based on proxies. Except of course: Secondly all the proxies appears to be correlated to the black line, because they have been chosen to do so. That is, the correlation to the black line is manufactured, and not a finding. The rest of the graph is made in a completely different manner, and the proxies are allowed to carry the signal for themselves. I think it is very interesting that you can see a small medieval warming period from the proxy data, but nevertheless one shouldn't be too eager to compare the right part and the left part of the graph, as the methods used are actually not the same. One can also show that the noise in the proxies will tend to pull the data towards the average and away from the extremes, which is exactly the lower rate of change and lower peaks you see. So that graph is really not very good, at all...
deleted 14y ago
[deleted]