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Hmm. Let me know when you have some scientific evidence and specific numbers related to these notions. If we're cooking up stories, how about this arbitrary "e

by mkempe 8y ago

Hmm. Let me know when you have some scientific evidence and specific numbers related to these notions. If we're cooking up stories, how about this arbitrary "explanation": Phytoplankton are plentiful. They're reproducing and dying and sinking in such vast quantities to the ocean floor that this floor is steadily growing a new layer, at a rate of a few mm per year. Hence the apparent sea-level rise, relative to the continents. The accumulation of biogenic sediment is accelerating with the rise in atmospheric CO2 because CO2 directly feeds the plankton.

southern_cross 8y ago
Am I correct in assuming that you're the type who needs a "study" in order to tell you what to think? Or are you the type who can use their own eyes and their own brain and do their own thinking and come up with their own conclusions - maybe ones that are eventually validated by studies after all, but perhaps only years or even decades down the road? I consider the first type a form of education-induced brain damage, BTW. And while I'm fairly well-educated myself, I've never been the type who needed the "crutch" of a study in order to figure fairly obvious things out. I don't remember the details, but I did once try to do the math on the whole CO2:H2O thing, since I hadn't seen it elsewhere. Estimated CO2 emission numbers are routinely published (to the extent that these can be trusted), and I started off with the simplifying assumption that CO2 and H2O are generated in equal amounts. This led to a small but real potential effect on sea level rise. (Although when I once discussed this in another forum some years back, someone there tried to insist that all of that water vapor just stays in the air - which I thought was rather bizarre!) But when I tried to make a more realistic assessment of the situation, I realized just how variable things could be (see examples below), and that I really had no good information to go on. Any numbers I came up with could vary widely based on my starting assumptions, so they weren't really worth very much in the end - kind of like the way so much "climate science" is done today! :) CO2:H2O production ratios, if fully oxidized. If not fully oxidized then the CO2 numbers drop and soot is produced instead. Methane: 1:2 Octane: 8:9 Benzene: 2:1 These are for very simple organic molecules. Once you get past a handful of carbon atoms the number of potential molecular configurations and corresponding ratios starts growing dramatically, and for something like coal the situation can grow extremely complex. I know your phytoplankton comment was meant as sarcasm, but such things might actually have a real effect over time. (You should probably do the math!) The buildup of organic matter, minerals, sediments from erosion, and "rocks" and such might very well be noticeable. Remember that, if land-building forces were to basically come to a halt, then eventually all of the continents would pretty much just erode completely away, leaving not much more than an Earth covered in seawater to some average depth.
- mkempe 8y ago
  The latter, of course! I'd be interested in your numbers. H2O is 2.5% of the atmosphere, so I can't see our CO2:H2O production having a significant impact in that respect; but still, an interesting angle since H2O is a major greenhouse gas. Estimates for biogenic sediment accumulation ranges up to 5 cm per thousand years -- two orders of magnitude smaller than current prediction of the rate of global sea-level rise.
  - southern_cross 8y ago
    Unfortunately I did this seat-of-the-pants calculation years ago, so I no longer have the numbers around. I do remember that using the simplistic 1:1 ratio the net result was considerably smaller than I had originally expected, although still measurable. But when I tried to figure out a more realistic ratio to use I kind of ran into a brick wall. See, for example, the typical molecular complexity of coal: https://en.wikipedia.org/wiki/Coal#/media/File:Struktura_chemiczna_węgla_kamiennego.svg https://en.wikipedia.org/wiki/Coal#/media/File:Struktura_che... (It's been a long time now, but if I remember my organic chemistry correctly each of those unmarked corners is a carbon atom, and each of those may have a hydrogen atom attached to it, and possibly more than one.) A transition away from coal and towards natural gas (which consists primarily of fully-combustible methane at a ratio of 1:2) should lead to both an increase in H2O output and a decrease in CO2 output as compared to coal. (A recent local power plant transition from coal to natural gas claims a carbon emissions reduction of 60%.) Using your 2.5% number, water vapor is already about 60x more common in the atmosphere than CO2 is at 0.041%, and I've seen estimates that it is probably about 15% higher now than it was in the past. (Presumably any H2O output above that has ended up in the oceans.) Given that as a greenhouse gas water vapor is at least 2x (IIRC) as powerful as CO2 and apparently also increasing at a steady clip, you'd think that folks would be paying more attention to this, but instead they just tend to ignore it. In fact they just like to ignore water vapor completely, except maybe when it leads to clouds and such.

by mkempe 8y ago

southern_cross 8y ago

Am I correct in assuming that you're the type who needs a "study" in order to tell you what to think? Or are you the type who can use their own eyes and their own brain and do their own thinking and come up with their own conclusions - maybe ones that are eventually validated by studies after all, but perhaps only years or even decades down the road? I consider the first type a form of education-induced brain damage, BTW. And while I'm fairly well-educated myself, I've never been the type who needed the "crutch" of a study in order to figure fairly obvious things out. I don't remember the details, but I did once try to do the math on the whole CO2:H2O thing, since I hadn't seen it elsewhere. Estimated CO2 emission numbers are routinely published (to the extent that these can be trusted), and I started off with the simplifying assumption that CO2 and H2O are generated in equal amounts. This led to a small but real potential effect on sea level rise. (Although when I once discussed this in another forum some years back, someone there tried to insist that all of that water vapor just stays in the air - which I thought was rather bizarre!) But when I tried to make a more realistic assessment of the situation, I realized just how variable things could be (see examples below), and that I really had no good information to go on. Any numbers I came up with could vary widely based on my starting assumptions, so they weren't really worth very much in the end - kind of like the way so much "climate science" is done today! :) CO2:H2O production ratios, if fully oxidized. If not fully oxidized then the CO2 numbers drop and soot is produced instead. Methane: 1:2 Octane: 8:9 Benzene: 2:1 These are for very simple organic molecules. Once you get past a handful of carbon atoms the number of potential molecular configurations and corresponding ratios starts growing dramatically, and for something like coal the situation can grow extremely complex. I know your phytoplankton comment was meant as sarcasm, but such things might actually have a real effect over time. (You should probably do the math!) The buildup of organic matter, minerals, sediments from erosion, and "rocks" and such might very well be noticeable. Remember that, if land-building forces were to basically come to a halt, then eventually all of the continents would pretty much just erode completely away, leaving not much more than an Earth covered in seawater to some average depth.

mkempe 8y ago
The latter, of course! I'd be interested in your numbers. H2O is 2.5% of the atmosphere, so I can't see our CO2:H2O production having a significant impact in that respect; but still, an interesting angle since H2O is a major greenhouse gas. Estimates for biogenic sediment accumulation ranges up to 5 cm per thousand years -- two orders of magnitude smaller than current prediction of the rate of global sea-level rise.
- southern_cross 8y ago
  Unfortunately I did this seat-of-the-pants calculation years ago, so I no longer have the numbers around. I do remember that using the simplistic 1:1 ratio the net result was considerably smaller than I had originally expected, although still measurable. But when I tried to figure out a more realistic ratio to use I kind of ran into a brick wall. See, for example, the typical molecular complexity of coal: https://en.wikipedia.org/wiki/Coal#/media/File:Struktura_chemiczna_węgla_kamiennego.svg https://en.wikipedia.org/wiki/Coal#/media/File:Struktura_che... (It's been a long time now, but if I remember my organic chemistry correctly each of those unmarked corners is a carbon atom, and each of those may have a hydrogen atom attached to it, and possibly more than one.) A transition away from coal and towards natural gas (which consists primarily of fully-combustible methane at a ratio of 1:2) should lead to both an increase in H2O output and a decrease in CO2 output as compared to coal. (A recent local power plant transition from coal to natural gas claims a carbon emissions reduction of 60%.) Using your 2.5% number, water vapor is already about 60x more common in the atmosphere than CO2 is at 0.041%, and I've seen estimates that it is probably about 15% higher now than it was in the past. (Presumably any H2O output above that has ended up in the oceans.) Given that as a greenhouse gas water vapor is at least 2x (IIRC) as powerful as CO2 and apparently also increasing at a steady clip, you'd think that folks would be paying more attention to this, but instead they just tend to ignore it. In fact they just like to ignore water vapor completely, except maybe when it leads to clouds and such.