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According to Accounting for water formation from hydrocarbon fuel combustion in life cycle analyses, water is created by burning hydrocarbon fuels. It seems like a major thing to exclude from "reasons the sea levels are increasing".

From the paper:

The annual global formation of water from combustion of hydrocarbon fuels from 2005–2015 amounted to an average of $1.2 \times 10^{13} kg⋅yr^{-1}$, as shown in figure 1. By comparison, the atmosphere is estimated to hold on average approximately $1.3 \times 10^{16}$ kg of water, while the global rates of irrigation-induced and natural evaporation are on the orders of $10^{15}$ and $10^{17} kg⋅yr^{-1}$, respectively.

I understand from the figures, the amount of water introduced into the atmosphere is small compared to irrigation and natural evaporation, but that is only dealing with water that is already there. This paper details that we are essentially pulling hydrogen out of the earth, combining it with atmosphere oxygen and creating water.

Water vapor is already listed as a GHG, so maybe it is just being swept along with that term?

I have to be making a connection that doesn't exist, right? Otherwise it would be noticed by someone / anyone else.

Make me understand why I am wrong to think that the creation of water by burning hydrocarbon fuels is adding to the amount of water in the oceans.

Thank you,

GrapefruitIsAwesome
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This Guy
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    the weight of the hydrocarbons burned is the same as the water and waste products so the net result is zero,you simply get more water and less hydrocarbons so nothing is added or removed from the system. – trond hansen Jul 30 '20 at 10:09
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    Thank you for the comment. Your comment is fine, but I'd like to point out that the material has now been transferred from one location ( fuel source ) to another ( atmosphere ). So, if we are transferring and transforming materials ( trees, natural gas, oil, etc.. ) from above sea level ( as in not previously displacing the ocean water ) into the atmosphere, why is it not accounted for in the hydrologic cycle? – This Guy Jul 30 '20 at 12:08
  • I suspect your source has the natural evaporation number a bit wrong. Roughly 70% of the Earth's surface is ocean, which is always covered with water. About a half of one percent of the Earth's surface is irrigated land, which is occasionally covered with water. Wikipedia and others put evaporation and precipitation at 50000 km^3 per year, or 5*10^17 kg/yr. 5 is on the order of 10 rather than 1. A factor on the order of a thousand makes more sense than on the order of 100. – David Hammen Jul 30 '20 at 23:05
  • @DavidHammen thank you for the comment. I understand that the comparison was made so that it highlights that the quantity of water generated is quite small compared to the capacity of the entire system. My concern is that there is an assumption that there is a set quantity of water in the system: it can't be removed and it can't be added to. Do you agree with that assumption? Or is it a fact that water can't be added or removed from the system? Thank you Sir – This Guy Jul 30 '20 at 23:37
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    There is an assumption that the amount of water in the system is nearly constant. It is known that it is not exactly constant. That it is not exactly constant is irrelevant. – David Hammen Jul 31 '20 at 07:53
  • @DavidHammen so, would you agree that the IPCC Fifth Assessment Report is using the assumption that there is a constant amount of water? I understand that the IPCC is the authority and leading body when it comes to these studies. Chapter 9 of AR5 lists that their precipitation model is only 82% correct and that it needs to be much better. Do you not agree that 100% should be the target and that science based models and formulas should contain as many variables as possible to represent the reality of the situation? Would it not be sound to understand the total amount of water? – This Guy Jul 31 '20 at 11:13
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    100% accuracy is unachievable, in any science. – David Hammen Jul 31 '20 at 11:15
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    Re Would it not be sound to understand the total amount of water? Not really. There's an apocryphal story about a scientist who was so intent on studying bugs that only lived on the north side of a certain species of trees suddenly emerge from the trees that he missed that the forest was on fire. Don't be this guy. – David Hammen Jul 31 '20 at 11:26
  • From IPCC AR5, Chapter 9 executive summary : their temp model is 99% correct, but "The simulation of large-scale patterns of precipitation has improved somewhat since the AR4, although models continue to perform less well for precipitation than for surface temperature. The spatial pattern correlation between modelled and observed annual mean precipitation has increased from 0.77 for models available at the time of the AR4 to 0.82 for current models. At regional scales, precipitation is not simulated as well, and the assessment remains difficult owing to observational uncertainties – This Guy Jul 31 '20 at 11:34
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    I'm simply trying to let people know that there is proof that the amount of water is increasing due to the combustion process. Coal, natural gas, biomass, natural forest fires all generate water. They dont simply evaporate liquid water, they transform fuel into water. I think this fact is not widely known or understood. And it is not even considered in the IPCC model,. I'd be fine with them listing that it is "insignificant", but it is not considered at all. Thank you for your time. I hope you can think about the possibility that it should be a factor. – This Guy Jul 31 '20 at 11:47
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    It is worth considering water can easily be removed , plant life converts water into sugar, and many biological process destroy water. You would need to compare the contribution to the larger water cycle. – John Jul 31 '20 at 14:31
  • Thank you for your comment @John. I think it could only be a good thing to understand how water is created and removed from the system. If we ignore the possibility of it contributing, then we won't have an opportunity to understand the bigger picture. The IPCC is effectively saying that there is still an 18% unknown part of the big picture. Maybe this is part of that 18%. it might be a fraction of it, it might be the full piece, but I think it merits study and consideration for inclusion in the model. – This Guy Jul 31 '20 at 14:53
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    "Self evident" may not be a scientific term but probably applies - I think it has been treated as insignificant with respect to sea levels because the mass of fossil fuels burned is so much less (1/10,000,000th) than the total mass of water on Earth. Knowing precisely won't change the big picture but other known contributions to sea level rise have error bars much bigger than that and are of greater importance and therefore greater scientific interest. Still, it surprises me that H2O produced approaches the total mass of FF's burned - but still less than ~ 3 t of CO2 per ton of FF's. – Ken Fabian Aug 05 '20 at 01:19
  • https://www.energy.gov/eere/fuelcells/water-emissions-fuel-cell-vehicles – This Guy Nov 25 '20 at 16:37
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    The premise is incorrect. Sea level is not what we need to look at. The water created is not put into the ocean although it ends up in the water cycle. We put it directly into the atmosphere. Anyone have that impact data? – Derek Feb 14 '24 at 01:00
  • @Derek I'd suggest it should generally end up in oceans, as oceans are basically the reservoir of excess water for the cycle. If the temperature and surface area of water available don't significantly change, the overall water in the balanced hydrologic cycle wouldn't change. The reaction would put it into the atmosphere as a vapor, but that'd mean greater condensation/precipitation until the cycle renewed its equilibrium state? – JeopardyTempest Feb 16 '24 at 10:47
  • Though that only considers the moisture itself... the fact that temp warms does means the amount of moisture held in the atmosphere does change, though again there's answers here indicating the energy released by the reaction scales as tiny, so the extra water in the water cycle is dominantly from other warming causes. – JeopardyTempest Feb 16 '24 at 10:47

2 Answers2

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1.2 x 10^13 kg equals 12,000,000,000,000 l water. One liter equals 0.001 m³, while one km³ equals one billion (1 x 10^9) m³. So we're supposedly adding 12 km³ water to the atmosphere per year.

According to wikipedia the total oceanic surface is about 361,900,000 km². If we spread the added amount of water over all the oceans, we end up with a sea level rise of 0,03316 mm per year. The german wikipedia page on sea level rise claims - based on the 5th chapter of the Fourth Assessment Report by the IPCC from 2007 - that the annual sea level rise between 1993 and 2003 due to thermal expansion was about 1,6 ± 0,50 mm.

Since we didn't take into account sinking surface above oceanic hydrocarbon sources or the increased atmospheric capacity for water vapour due to heating, which both are connected to the effect you are interested in, I'd estimate there is an existing, but almost negligible contribution to sea level rise. Other effects contribute way more - and all of them will likely peter out, once we reduce fossil fuel consumption significantly.

Erik
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  • Thank you for your answer Erik. Can I summarize your answer as "The water created is such as small drop in the bucket, that it's not worth considering."? – This Guy Jul 30 '20 at 12:17
  • That is my interpreation of my calculations. Also without me verifying the numbers the paper you cite claims @EricRamljak – Erik Jul 30 '20 at 12:19
  • Thank you for taking the time to respond @Erik. It is fair to say that. I would recommend reviewing the paper. Have you considered the effect of water generation from burning things previously? I've only just considered it and found it weird that it does not seem to be well studied or even considered in general publications. – This Guy Jul 30 '20 at 12:36
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    I did some rough calculations yesterday pondering an answer to that question and got a similar result -- the amount of water created in this process is orders of magnitudes smaller than the other aspects of the hydrological cycle. – jeffronicus Jul 30 '20 at 15:07
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    You're off by a factor of ten somehow. Your value should be 0.03316 mm, or 33.16 μm. In other words, completely negligible. – David Hammen Jul 30 '20 at 15:30
  • Thank you for your comment @jeffronicus. I can appreciate that view and speculation. I would like to examine the difference between the two methods of adding water to the atmosphere: water creation and water evaporation. While evaporation defines the movement of water from one location and state to another, water creation defines the addition of water to the hydrological cycle. The current assumption is that we have a stable quantity of water in that cycle, but actually the amount of water is fluctuating, and even incrementing. Why is this not even in the current model of the cycle? – This Guy Jul 30 '20 at 15:38
  • Thank you for your comment @DavidHammen. The observed numbers aside ( I hope you can appreciate that they are considered within a reduced scope and are an estimation ); would you be willing to comment on or answer the original question? The paper which I cite concludes that water is created when hydrocarbon fuels are burned, so if you agree with that statement; why is that not considered in the hydrological cycle? – This Guy Jul 30 '20 at 15:48
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    @EricRamljak -- The amount of water created by burning hydrocarbons is at over four orders of magnitude small than the amount of water that passes annually through the water cycle. If doubt that scientists know the numbers to three degrees of precision. This means that the quantity you are concerned with is over an order of magnitude smaller than the uncertainty. Those are the kinds of quantities one ignores. – David Hammen Jul 30 '20 at 23:10
  • @DavidHammen yeah, you're right, I think I converted from cm to mm twice, sorry. – Erik Jul 31 '20 at 06:35
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    Note well: The "1,6 ± 0,50 mm" quoted in this answer is due to thermal expansion of the oceans. Water added to the oceans via melting ice adds about the same amount to sea level rise. The net sea level rise has less uncertainty than does the contribution of each contributor because the net sea level rise is somewhat directly observable while the individual contributions are more indirect. Nonetheless, the uncertainty in the net sea level rise is orders of magnitude greater than 33 μm/year. – David Hammen Jul 31 '20 at 08:01
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    Which means that that 33 μm/year can more or less be ignored. – David Hammen Jul 31 '20 at 08:02
  • @DavidHammen -- Please, consider that the study cited by me, lists that 12 cubic KM as an estimate. One of the conclusions of the paper is "Thus, water formation is deemed significant enough to be considered for inclusion in future life cycle analyses of the water intensity of fuel production and use". It is also the only study that I can find which details or even admits the amount of water created by burning hydrocarbons fuels. I continue to be puzzled that there are no reports detailing that information. I will not accept this answer you have provided – This Guy Jul 31 '20 at 11:25
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    @EricRamljak David didn't provide any answer, he just corrected mine. We proofed to you, that while there is an inflow of additional water, the total amount is insignificantly small. And yes, this "production" of water can be considered for future life cycle analyses - of fuel production - but not for analyses of the whole water cycle/sea level rise. Maybe you should point out more clearly what question you want to have answered. – Erik Aug 01 '20 at 11:34
  • Erik, I think you are right about the question I am asking; I seem to be a bit flaky. Perhaps I will post a new, smaller question. I can accept your answer, but it would need to exclude the estimated value from my source. I'd very much appreciate it if you could provide your own source for the worldwide value of water being created. You use it as a fact, but it is simply an estimated value. So I feel that your answer is flawed at a basic level and you have unfortunately not proved anything.Thank you all for your time and consideration. – This Guy Aug 02 '20 at 18:12
  • @EricRamljak Wait, you expect me to do my own estimation on the issue? – Erik Aug 03 '20 at 08:09
  • I mean, I'd prefer an answer based on facts rather than an opinion based on speculation. I hope that's not too much to ask from a scientific forum. – This Guy Aug 03 '20 at 14:33
  • @EricRamljak the opinion is based on the speculation done in the source you provide. Since there seems to be no additional work on the issue, where do you propose facts should come from? – Erik Aug 03 '20 at 14:39
  • I would accept the answer as "there has not been enough study on this subject to prove or disprove that burning hydrocarbons fuels can contribute to rising sea levels". You can't honestly expect to answer a question by saying "It probably doesn't matter, but I dont have any facts to back this up." The answers should come from papers or references which support your answer. I'm bothered by the fact that there has not been additional work on the issue. – This Guy Aug 03 '20 at 16:39
  • @EricRamljak then feel free to answer your own question, or explicitly state you want/need an answer backed up by several scientific sources. As the question currently is, to me my calculation seems sufficient enough to show that the contribution as estimated by your source is negligible. – Erik Aug 03 '20 at 17:41
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The current popular view is that the total quantity of water on the planet is a constant value. This appears to be an assumption. There has not been enough study and information published on this subject to prove or disprove that burning hydrocarbons fuels can contribute to rising sea levels.

Thank you to those who have provided comments and an answer. This has been a good learning experience.

Water Cycle

The Role of Anthropogenic Water Vapor in Earth's Climate provides a review of the positions taken by various organization concerned with climate about the role of water vapor in the Earth's climate system. I encourage you to review / read this yourself.

Some key items from that review to consider:

"the burning of one gallon of gasoline produces 3,914.6 grams of water. This is equal to 8.6 pounds of water, which has a volume of 1.033 gallons"

"There was about 22 trillion cubic feet of natural gas burned in the United States in 2006...so the water vapor proburninduced (sic) in a year from burning natural gas is 263.4 billion gallons of water. This is per year; per day the figure is 722.4 million gallons."

This Guy
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    The earth produces ~35 cubic kilometers (qkm) of magma each year, mostly in the oceans. Your figure is around 1 qkm, if I am not mistaken. I am not sure if that has a maesurable precipitaion in slr, even measured with satellites, but in simple terms it plays no role. –  Sep 13 '23 at 15:41
  • Hey, thanks for the comment. It does seem extremely strange that the IPCC reports do not even mention this at all. Most of the models and explanations state that the amount of water in the world does not ever change. That it does not get destroyed and that it is not created, which seems to be very incorrect... Combustion converts hydrocarbons into water, so why is it not considered? What about compound effects, yearly additions from this? It's almost like our sensitive planet can be affected by small, SEEMINGLY inconsequential changes. – This Guy Sep 13 '23 at 18:28
  • not only is the water balance NOT assumed to be zero it is calculated and accounted for in everything from tectonics cycles to year loss to space. https://earthscience.stackexchange.com/questions/9488/how-much-water-is-the-atmosphere-losing-to-space – John Feb 16 '24 at 00:42