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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 2601 to 2650:

  1. “It’s almost like a cult.” Activists shout down rural renewable energy projects

    One of the effective ways clean energy advocates can fight back against this sort of harrassment is continuing to advocate for higher taxes on the fossil fuel industry, and tax credits for green energy installations.  

  2. Antarctica is gaining ice

    Bart @ 541:

    What Rob said to you.

    You say the change in the average is "interesting". So what? The average went up a lot when 2022 gets added to the series.

    • In 2007, the low value of about -350 would have dropped the previous average by 70 Gt/yr, because it was only the 5th value in the series (up to that point).
    • By 2010, the series has grown to 9 values, so that -380 value would have dropped the average by roughly 65 Gt.
    • By 2015, the time series has grown to 14 values, so the additional value of -350 would have dropped the average by 25 Gt.

    This is simple arithmetic. Short time series see big jumps in the average when a single large value is added. It really has very little meaning.

    You then go on to postulate "how much will the SMB increase"? You are speculating that this one-year large positive value is the key to the future trend. That is highly speculative. Not just uncertain - highly speculative. You are taking one value from a noisy signal, and treating it as if it represents a long-term trend.

    You are focussing on the noise represented in a single value, and it really is not a good idea.

  3. “It’s almost like a cult.” Activists shout down rural renewable energy projects

    David-acct said:

    "NIMBY does create some issues for worthwhile projects. A 375 Mw wind farm will require approx 3000 acres (assuming 80 acres per megawatt) or 35-40 square miles (assuming 10 mw per square mile. A typical gas generating plant generating 250-300MW will have a foot print of approx 15-20 acres. Approx 2 acres of land used for the actual turbine, & roads means the foot print for the 375mw is 750 acres, not including lower farm production.

    So while it is regrettable, it remains understandable."

    I am a little unclear what is meant by this comment. Is it about the well-head installation or a gas-fired power plant? If either one, it has in almost no case delivered the gas to the point of use. Gas pipeline rights of way need inclusion, and for the latter the former shouldbe added to the area of the gas fired electric plant. Then there is the territory at the surface affected by some types of drilling, and the territory below where water supplies may be affected, plus the surface area affected by that. How does that math come out??

  4. Rob Honeycutt at 09:19 AM on 10 March 2023
    Antarctica is gaining ice

    Bart @541... "After last year the average has changed, which is interesting by itself."

    Again here, you're focusing on one data point, where the abstract you post is focused on the long term uncertainties. The 2022 datapoint may technically alter the 20 average, but that's pretty darned meaningless since the following years may likely revert to the long term mean.

    What researchers are trying to do (to my understanding) is reduce their uncertainties for long term ice mass loss as it pertains to sea level rise contributions. Having a higher degree of confidence on whether we're going to see 0.3m or 1.3m of sea level rise by 2100 is very important information for the broad purposes of governments and societies to inform them how to prepare.

  5. Antarctica is gaining ice

    Bob Loblaw @ 539

    I don't think focussing on the noise is a good idea ;-)

    When we just look at the GRACE data then the year 2022 is one in a row of 20. After last year the average has changed, which is interesting by itself.

    But during this 20 years things have changed. The extent of the sea ice has declined. So more water vapour comes to the continent, which gives more precipitation. The question is how this works out. The last year gave us a hint that it can add a lot to the Surface Mass Balance. The next question is: how much will the SMB increase, and how much will the discharge increase. Of course, that's very uncertain. In the paper I called it says in the abstract:

    The surface mass balance in SSP5–8.5 simulations shows a pattern of strong decrease on ice shelves, caused by increased melting, and strong increase on grounded ice, caused by increased snowfall. Despite strong surface and basal melting of the ice shelves, increased snowfall dominates the mass budget of the grounded ice, leading to an ensemble mean Antarctic contribution to global mean sea level of a fall of 22 mm by 2100 in the SSP5–8.5 scenario. We hypothesise that this signal would revert to sea-level rise on longer timescales, caused by the ice sheet dynamic response to ice shelf thinning. These results demonstrate the need for fully coupled ice–climate models in reducing the substantial uncertainty in sea-level rise from the Antarctic Ice Sheet.

  6. Antarctica is gaining ice

    MAR @ 538:

    Yes, the linear regression vs. "average" is a factor. The page I linked to shows a graph that starts at 0 ice loss in 2002 and ends with the current accumulated ice loss. It points out two specific values:

    1. +65 Gt in October 2002
    2. -2808 Gt in Febraury 2020

    ...for a total change of 2873 Gt in 19.3 years. That is a change of 149 Gt per year. It is not a regression of the time series. It also takes the maximum of 65 Gt at a time slightly after the record begins, and chooses the minimum in February 2020, not the final value at the latest point on the series.

    As I said - noise in the system. Short record, year-to-year variability. Add close to a year at the start; add a couple of years at the end; results change. Not a surprise.

  7. michael sweet at 04:52 AM on 10 March 2023
    Methane emissions from Siberian sinkholes

    This you tube video demonstrates blowing up a soda bottle using dry ice and water.  Nothing ignites.  I used to telll the cop on our High School campus when I was going to do this demonstration, it sounds like a gunshot.  I have blown a watermelon to smithereens by dong this explosion in a one liter bottle inside the watermelon.  Definately an explosion.  Note the tremperature is below zero C.

    The energy for the explosion comes from the freezing water causing the dry ice to sublimate (turn into gas).  The gas pressure builds until the bottle fails and explodes.  Soda bottles are much louder than water bottles.  (water bottles are thinner, soda bottles have to resist the pressure inside the bottles.)

  8. Antarctica is gaining ice

    Bart Vreeken @ 537:

    Ahh, so you are focussing on the noise, not the signal. The year-to-year variation is large, and one year of adding ice does not a trend make. So, there has been a year where close 400 Gt was added - and there have been four years in the record you show where 300-400 Gt per year was lost (2007, 2010, 2015, 2018).

    The "rebound" of 2022 is simply a strong positive departure from the long-term trend after several years where individual years were below the long-term trend. You might benefit from reading about Regression toward the Mean.

    In a noisy, short data set, adding or removing one exceptional year will have a strong effect on the average. With only 20 years of record, +400Gt in one year will shift the average by 20 Gt. This is not exactly ground-breaking analysis.

    And in continental-scale ice sheets, it takes decades to centuries for mass added in the central areas to reach the perimeter. You are familiar with the phrase "glacially slow", aren't you?

    So again, exactly what is your point, other than "this is interesting"? And what, exactly, do you want me to read about in the paper you link to? Refer to a diagram, section of text, or something concrete.

  9. Antarctica is gaining ice

    The difference between the 114Gt/y and the 151Gt/y isvery likely that the former is an average and the latter a linear rate of loss calculated using OLS. That NASA (Vital Signs) graph showing the 151Gt/y also gives a 20.5-year mass loss Apr2002-Nov2022 of 2,352Gt which averages to 115Gt/y.

  10. Antarctica is gaining ice

    Hi Bob @534

    I don't see a clear rebound effect in my figure. 

    And of course the mass gain of last year shall be exceptional. But at least it's an interesting thing to notice. And maybe the increasing precipitation can offset the increasing discharge in the coming years as we can read in the article below. As you say, the average mass loss is now something like 114 Gt per year. That's much less then the 151 Gt we read about on the website of NASA (Vital Signs).

    tc.copernicus.org/articles/16/4053/2022/tc-16-4053-2022.pdf

  11. Antarctica is gaining ice

    One other thing to note in Bart Vreeken's graph in comment 533.

    Bart's graph has a dotted line in it, and an equation in the upper right corner, which I presume is the regression equation for the line.

    Note that the indicated slope is -0.0672 (so, almost zero), and the intercept is -113.83. This indicates an average mass loss of 113.83 Gt per year. A bit lower than the 149 Gt per year in the web page I linked to in comment 534 - but the page I linked to does not include the 2021 and 2022 data, which pull the average up.

  12. Antarctica is gaining ice

    Bart Vreeken @533,

    You appear to be plotting out the GRACE/GRACE-FO data as per this NASA web page (which shows data to Oct 2022).  This gravity data does not measure Sea Ice which is floating. And for clarity, it is not Surface Mass Balance which you correctly say had an exceptional year last year (as per this NSIDC post of January 2023, snowfall being high enough to "completely offset recent net ice losses from faster ice flow off the ice sheet for this assessment period. Most of the past decade has seen annual net losses of 50 to 150 billion tons."

    Antarctic Surface Mass Balance

    So a record year for the 2023 Antarctic Sea Ice Extent minimum as well as a record year for the 2022 Antarctic Surface Mass Balance.

    Antarctica doesn't get a lot of attention, compared to the Arctic cryosphere. Certainly for Antarctic Sea Ice, the mechanisms driving the variations is a lot less straightforward in the Antarctic.

  13. Antarctica is gaining ice

    Bart Vreeken @533:

    What exactly is your point? The links between sea ice area and land ice mass are not simple, and have been discussed in the detailed sections of the blog post and earlier comments.

    In your graphic, it is obvious that the two major years of land ice gain (2016, 2022) follow several years of strong mass ice loss. This is easily explained as a rebound effect.

    This web page on Grace data has an embedded video with data to 2020. Rather than portraying the annual changes it shows the overall trend in the absolute value from year to year. Clearly, Antarctic land ice is losing mass in the long term - with short terms ups and downs.

    Are you perhaps over-analyzing the significance of short-term changes, as is often done with temperature changes? (As seen in The Escalator).

    The Escalator

  14. Bart Vreeken at 23:07 PM on 9 March 2023
    Antarctica is gaining ice

    Antarctica Annual Rate of Change

    It looks like the Antartican Ice Sheet had a very good year, as far as we can see. At least, the mass balance over the period november 2021 - november 2022 was far positive. This can be due to the very low extend of the sea ice. The Surface Mass Balance over the melting period of last year turned out very positive. I don't read much about this, the focus in de media is on the low extent of the sea ice. Any thoughts about this?

    I did expect a new update of de GRACE data of December 2022, but it comes late again. 

  15. It's not urgent

    Eddie:

    SkS did a series on the ocean acidification issue a number of years back.

    Part 0 provides an index to the series.

    After it was complete, it was turned into a downloadable booklet.

  16. It's not urgent

    MARoger@

    "The net carbon sink into the oceans is far more predictable than the carbon interchange in/out of the biosphere."

    Using the global ocean as a carbon sink has consequences for biodiversity, increasing acidification. There's no free lunch, and no eternal waste disposal for the Anthropocene, I gather. I'm not up to date on the latest research; I left the ocean as a sink with Roger Revelle. I will update my understanding for sure.  There are no positives in any of these GHG matters.

  17. Rob Honeycutt at 15:25 PM on 9 March 2023
    Which state is winning at renewable energy production?

    David @9... "The shift of the demand curve effectively raises the market price of the product."

    Not necessarily. Specifically, with RE systems, what the tax credits are doing is making up for externalities. RE is operating in the energy marketplace and is therefore in competition with legacy energy generation from FF sources. Those FF sources have an effective advantage in that the byproducts of their uses have quantifiable, but uncaptured, harms to the global environment. 

    Regardless of whether a tax credit is making the energy product cheaper or making the RE provider more profitable doesn't matter. What matters is the overall benefit to the RE energy companies in lieu of direct taxes on carbon emissions.

    Same applies to EV makers. They are operating in the automobile market with, initially, products that cost more to manufacture. Tax credits level the playing field between EV's and ICEV's for a time period while economies of scale can be achieved by EV makers. Remember, all the auto tax credits have sunsets based on the numbers of vehicles sold. 

    In the case of EV's, clearly the tax credits are benefiting the buyer because the cost of EV's is just now (or within a year or two) achieving parity with the cost of manufacturing an ICEV. Thus, up until now those tax credits have served to bring the cost of EV's in line with ICEV's. 

  18. “It’s almost like a cult.” Activists shout down rural renewable energy projects

    David-acct:

    Wind turbines may be spread over a large area, but not all the land in that area is removed from other functional uses. Farmers can easily use most of the land in that 750 acres, since the only place that can't be farmed is the actual base of the towers and any road infrastructure needed for maintenance.

    A picture from the North Sea area in Germany:

    German wind farm

  19. Which state is winning at renewable energy production?

    David-acct:

    The change in price in response to shifting supply or demand depends a great deal on the "elasticity" - basically, the slope of the supply or demand curve. Some products are very inelastic - prices are barely affected by large changes in supply or demand - while others are very elastic - small changes in supply or demand can lead to large price changes.

    Some products are essentials, and people will continue to pay for them even if prices go up a lot. Luxuries are often more elastic - people will readily reduce purchases if they think it's too expensive.

    As for who benefits from a credit - surely the individual buyer pays less in the end (the initial payment, less the tax rebate), even if the producer pockets more? Electricity is not a particularly elastic demand - people need it, and changing the amount they use is not easy. What happens if tax credits are given for renewable generation is that there is (hopefully)  a shift from non-renewable to renewable. It's not a function of the elasticity of electricity overall - it is a shifting of the demand from one source to another. Some purchases get a benefit, while others (still using non-renewable resources) do not.

    Do you have specific references to support your closing claim that 70-90% of the benefit goes to the seller?

  20. Methane emissions from Siberian sinkholes

    My favourite non-igniting explosion is probably the water heater that the Myth Busters blew up.

    Heat and pressure, That's all it takes.

  21. “It’s almost like a cult.” Activists shout down rural renewable energy projects

    NIMBY does create some issues for worthwhile projects. A 375 Mw wind farm will require approx 3000 acres (assuming 80 acres per megawatt) or 35-40 square miles (assuming 10 mw per square mile. A typical gas generating plant generating 250-300MW will have a foot print of approx 15-20 acres. Approx 2 acres of land used for the actual turbine, & roads means the foot print for the 375mw is 750 acres, not including lower farm production.

    So while it is regrettable, it remains understandable.

  22. It's not urgent

    PM (may I call you PM?):

    There is a classic line at the end of  the movie Casablanca, where the police captain (Renault) says to Rick (the main character played by Humphrey Bogart), "round up the usual suspects". The connotation is that the police have a list of people they know are usually associated with many crimes, and they'll take the blame.

    I'm basically pointing out that there are certain players in the climate change "debates" who will most certainly take the least charitable interpretation of that quote. We've seen them do similar, many times before.

  23. Which state is winning at renewable energy production?

    to bob & Nigelj at 6 & 7

    There is a lot of misunderstanding on tax credits and who benefits from those tax credits, Those misunderstandings persist simply because the general public has a poor grasp of the basics of micro economics and the supply and demand curves. Tax credits which buyer obtains a reduction of their income tax artificially shift the demand curve. The size of the shift is a function of both the size of the credit and the natural demand for the product without the tax credit. The shift of the demand curve effectively raises the market price of the product. The buyer is still paying at or near the natural market price ( which is the gross price less the tax credit or some portion thereof depending on the elasticity of the product). As such, most of the benefit of the buyers tax credit goes to the seller in the form of higher sales price. A reasonable estimate in the case of EV's and home renewable products is 70-90% of the benefit effectively goes to the seller.

  24. PollutionMonster at 10:49 AM on 9 March 2023
    It's not urgent

    Bob Loblaw @21

    I am unsure who "The Usual Suspects" are. I am pretty good at debunking  obvert denial, but I still have a knowledge gap when it comes to the subtler aspects of climate change.

  25. Methane emissions from Siberian sinkholes

    There is all those lovely videos of SpaceX experiments failing cryo tests. eg  www.youtube.com/watch?v=sYeVnGL7fgw I think most people would call them explosions, despite liquid nitrogen not being ignited.

  26. “It’s almost like a cult.” Activists shout down rural renewable energy projects

    And on the other side of the "pond"...

    Three non-violent Insulate Britain activists have been jailed for telling juries why they were protesting.

    Court restrictions on climate protesters ‘deeply concerning’, say leading lawyers by Sandra Laville, Environment, The Guardian, Mar 8, 2023

  27. It's not urgent

    I"m with Rob. The writing of that specific sentence could be clearer. The "50% chance" part is definitely associated with the "staying below 1.5 degrees", but the comma that follows that separates the "50% chance" probability from the "risk of setting off irreversible chain reactions".

    Two possible re-writes that would make the writer's intentions clearer:

    1. "The popular idea of cutting our emissions in half in 10 years only gives us a 50% chance of staying below 1.5 degrees [Celsius]." It also brings a "risk of setting off irreversible chain reactions beyond human control."
    2. "The popular idea of cutting our emissions in half in 10 years only gives us a 50% chance of" avoiding two outcomes: "staying below 1.5 degrees [Celsius], and the risk of setting off irreversible chain reactions beyond human control."

    Expect "The Usual Suspects" to insist that the only possible interpretation is the one that fits their preconceived notions of Greta Thunberg.

  28. Rob Honeycutt at 08:14 AM on 9 March 2023
    It's not urgent

    Hm... Yeah, those are quotes from 2019 and I think she's probably conflating two issues. One being the likelihood of staying below 1.5°C or 2°C, and the other being the likelihood of setting off irreversible feedbacks. To my understanding, they're two different issues with very different confidence levels. 

  29. PollutionMonster at 07:38 AM on 9 March 2023
    It's not urgent

    Most of the quote is here in this NPR article. Risk of setting off irreversible chain reactions NPR.

    I would have to reread the book to get the exact quotes, I read in local bookstore.

    ""The popular idea of cutting our emissions in half in 10 years only gives us a 50% chance of staying below 1.5 degrees [Celsius], and the risk of setting off irreversible chain reactions beyond human control." Thunberg

     

  30. wilddouglascounty at 07:25 AM on 9 March 2023
    The little-known physical and mental health benefits of urban trees

    Little known? Ask any kid on a playground with one large tree on it where they want to play. Actually, you don't even have to ask: use your eyes!

  31. Rob Honeycutt at 07:22 AM on 9 March 2023
    It's not urgent

    PM @17... Would you have the precise quote from Thunberg's book related to "50% chance of runaway greenhouse effects beyond human control at 2°C"? 

    My suspicion is that's not an entirely correct assessment, though I'm confident Thunberg's book went through a thorough review by researchers prior to publication. My understanding is, past 2°C we move into a realm of much greater uncertainties. Also, even at 2°C significant feedbacks (say, from methane releases) remain long tail uncertainties. But I could be wrong.

  32. Rob Honeycutt at 07:14 AM on 9 March 2023
    Methane emissions from Siberian sinkholes

    Dennis... Getting things wrong is part of learning. We all get things wrong from time to time. The only true error is when we fail to learn from our mistakes.

  33. PollutionMonster at 07:11 AM on 9 March 2023
    It's not urgent

    I read all the responses, and I want to thank all of you. :) Climate justice is a major part of climate change. That rich nations including the United States, France, and United Kingdom need to reach zero emissions by 2030 so that poorer nations have time to develop and have some emissions until 2050.

    Thunberg in her book referenced some specific page of the IPCC page 100 or so stating that there is a 50% chance of runaway greenhouse effects beyond human control at 2C and only 34% chance at 1.5C. Is this true? That there really is that high a chance that climate change will be the end of everything? Did I misread? I haven't read the source material, navigating the IPCC report is difficult.

  34. One Planet Only Forever at 06:32 AM on 9 March 2023
    “It’s almost like a cult.” Activists shout down rural renewable energy projects

    Cult-like expressions of angry opposition to helpful developments are being driven by passionate belief in harmful misunderstanding.

    That is a common tactic of people who likely know what is harmful and helpful but want to benefit from the ability to harmfully mislead "common people". And it is happening on many issues, not just climate change.

    Too many people are too easily misled because there is no effective penalty mechanism. Commercial product marketers can be penalized for being misleading. But there is no comparable penalty for being politically misleading.

    It is important to remember that even a "renewable energy development" can have harmful aspects hidden by 'a focus on the positives'. The important requirement is full understanding of the negatives with the set of 'least negative' alternatives being considered to be the only viable development alteratives.

    That requires the development of regional populations that will be governed by learning to be less harmful and more helpful to people who need assistance.

    Everyone does not have to learn to be less harmful and more helpful. There just have to be enough helpful people to effectivey limit the harm done by attempts to benefit from harmful misunderstandings.

  35. Methane emissions from Siberian sinkholes

    Moderators

    Sorry, please remove anything not right or the comments in their entirety. Thanks.

    Moderator Response:

    [BL] If we wanted to, we would have. Usually we start with nudging users to remind them of proper posting etiquette. The initial goal is to make sure that users do not wander too far off, before things reach the point where we have to start editing or deleting posts.

     

  36. One Planet Only Forever at 05:36 AM on 9 March 2023
    It's not urgent

    MA Rogers has correctly clarified that the total harmful warming impact is what matters. Limiting the impact to 1.5 C needs to continue to be the focus. And the reality that the peak impact will almost certainly exceed 1.5 C needs to be understood to mean that wealthy people today need to be paying for safe/harmless technological extraction of CO2 from the atmosphere. That extraction will be expensive and never be profitable. And the spending of tax money on it rather than other things will never be "most" popular.

    That is the challenge. Leadership has to do something unpopular and unprofitable to benefit future generations. The diversity of developed socioeconomic-political systems is tragically lacking in the development of that type of leadership. And it is now undeniable that humanity only has a future if it develops governing of all significant human activity in ways that understandably limit and correct harm done.

    A related point is that it is harmful to cause increased CO2 to be absorbed in the oceans. The fact that CO2 will continue to be absorbed in the oceans is not a positive.

    Also, a lack of significant methane release from massive thawing of permafrost (a miss named item) is not a helpful positive.

    It is essential to remain focused on the need to end harmful activity regardless of its developed popularity or profitability abnd related popular 'perceived to be positive' misunderstandings (and that applies to authoritarian as well as democratic governing).

  37. At a glance - Is Antarctica losing or gaining ice?

    The CO2 615ppm limit for the East Antarctic ice sheet remaining stable seems to me somewhat optimistic.

    One of the 25 drainage basins used to measure ice sheet mass loss in East Antarctica (Wilkes land) has lost 400 Gigatons (i.e. 400 Cubic Kilometres) of ice in the last 20 years, the fourth highest of all the basins, and comprising about 15% of the total ice mass loss of 2,500GT. The highest three are in West Antarctica. 

    Every time a new field survey is undertaken, it generally seems to come up with more bad news about the vulnerability of this apparently solid ice sheet.

  38. It's not urgent

    According to the following article, we are on the precipe of multiple climate tipping points. As they say, "Hold onto your hat, we're in for a wild ride."

    Risky feedback loops are accelerating climate change, scientists warn by Emma Newburger, Climate, CNBC, Mar 6, 2023  

  39. It's not urgent

    EddieEvans @13,
    The net carbon sink into the oceans is far more predictable than the carbon interchange in/out of the biosphere. There is still some uncertainty and re-assessment (eg Watson et al 2020) in the matter but generally the only big variable is the ocean surface temperatures. So as long as we prevent massive SST rises, I would think it is safe to say "the global ocean will continue to act as a viable carbon sink." The actual size of that sink over the coming millennium will thus depend on how well we do preventing AGW but otherwise it's size is fairly predictable. What is far less predictable under AGW is the biosphere as a source/sink.

    You also raise the threat of methane, this usually focusing on natural feedbacks and the melting permafrost. In the past I was rather worried by the poor coverage of this subject in the scientific literature but having dug into the subject I now feel more comfortable about it. Additionally the absence of significant methane fluxes resulting from the significant permafrost melt in recent decades is a reassuring sign.

  40. It's not urgent

    "These extractions from the atmosphere are additional to the natural draw-down of CO2 into the oceans.)"

    And we have no idea if, at all, the global ocean will continue to act as a viable carbon sink, not to mention methane. Then there's the political will and economic resources to make the abrupt ideological and technological changes needed, assuming that critical tipping points were not breached long ago. I'm assuming that we don't know everything to know about the neew climate change and our test-tube earth mentality.

     

  41. It's not urgent

    PollutionMonster @10,

    You ask about the timing for reaching net zero carbon. That single timing doesn't properly capture the task in hand.

    The science strongly suggests that increasing global temperatures by more than +1.5ºC risks potential dramatic climate change. To prevent such rise, there is just one scenario presented within the IPCC AR6 that fits the bill - SSP1-1.9.

    AR6 SPM Fig8.a

    This SSP1-1.9 scenario does include a timing of 2050 for net zero carbon but it also requires a halving of global net carbon emissions by 2030 and large net negative carbon emissions post-2050. These net negative emissions amount to roughly extracting atmospheric CO2 equal to all the emissions post-2007 and storing them away safely. (There are many saline aquifers around the world which this CO2 could be desolved into after its extraction from the atmosphere. These extractions from the atmosphere are additional to the natural draw-down of CO2 into the oceans.)

    But it seems it is only the 'net zero' message that is being heard by politicians. So calling for an earlier 'net zero' is probably a useful message.

  42. It's not urgent

    "PollutionMonster at 14:13 PM on 8 March 2023"
    "How urgent is it?" is a value question. Another value question is "How much threat to diversity does humanity's anthropocentrism" cause to the long-term survival of species-populations in the wild (10,000 years)? And I agree, how do we quantify "How much threat"?

    In an anthropocentric (human-centered) context, judging from what I'm witnessing, we were out of time long ago.

    I need only point to the proliferation of nuclear warheads and greenhouse gases to bolster my case. I don't see much genuine effort by governments and corporations to do the real work, and make long-term decisions for the benefit of humanity and biodiversity's long-term existence; we continue to pass the buck to future generations.

  43. Methane emissions from Siberian sinkholes

    Ah, I might add to "burst," rather than "explosion,"  a synonym for grazing cattle's flatulence, "bursting" gut gas.

  44. Methane emissions from Siberian sinkholes

    Maybe "burst" is a better word for the release of pressure from the methane's underground vault?

  45. Methane emissions from Siberian sinkholes

    Again, Explosion does not equal ignition. Think about what an explosion really is. Your "ignition" type is when have a rapid chemical reaction generating large local gas pressures which then expand when any containment broken. Chemical reaction (needing ignition) isnt the only way to generate large gas pressures though. This paper goes into the process much more deeply than news articles. Clearly no ignition.

  46. PollutionMonster at 14:13 PM on 8 March 2023
    It's not urgent

    Hi, I just read the book No One Is Too Small to Make a Difference by Greta Thunberg. Wow, what an emotional rollercoaster. I've played the Cranky Uncle game for hours, taken the edx101 course, surfed the skeptical science website, and argued with deniers.

    Book no one is too small Greta Thunberg

    Yet, only in 2022 have I heard about net zero emissions. Even then, I thought it was by the year 2050. Greta Thunberg makes the case that global climate change is an existential urgent crisis. That we need net zero by 2030. Is this really true?

    As a millennial I feel a lot of the same emotions that the older generations are out of touch when I say I cannot get a job or having trouble with the basics like a roof over my head, running water, heat in winter. I find I get scolded by the older generations and they offer out of touch simplistic solutions blaming the victim or even calling me a liar.

    Did I get distracted by the pandemic, George Floyd's murder, and possible nuclear war between Russia and Ukraine? With all my climate activist since 2016 did I really miss that we only have a 50% chance to avoid a climate catastrophe of runaway greenhouse effect if we go for a 2 degree Celsius increase by 2050 or whatever Thungberg said in her book?

    How urgent is climate change? Thank you in advance. :)

  47. Rob Honeycutt at 11:50 AM on 8 March 2023
    Methane emissions from Siberian sinkholes

    Dennis... Reading the article you link to, I believe they're using the term "explosion" the same way you would say a balloon "explodes" if you blow too much air into it. There is no "source of ignition." The pressure is merely reaching a point to where the ground above the methane build up catastrophically fails to hold it in.

    Note that the before and after photos shown at the end of the article don't indicate any fire or charring around the crater, suggesting there was no actual "ignition" event related to the formation of the crater.

  48. Methane emissions from Siberian sinkholes

    @scaddenp

    I'm asking a question. When the methane explodes, as it clearly can, what is the source of the ignition?

    https://siberiantimes.com/other/others/news/scientists-call-for-urgent-increase-in-monitoring-potentially-explosive-permafrost-heave-mounds/

    Moderator Response:

    [RH] It's appreciated when you utilize the link tool to activate your references.

  49. Methane emissions from Siberian sinkholes

    I cant see anything in these that suggest the methane is igniting (explosion != ignition). In fact several of your sources explicitly discuss the gas blowout mechanism which I believe is what causes these. It is just build up a huge pressure from methane release until ground-strength is exceeded.

    Pretty much same mechanism that causes gingerbeer or sauerkraut explosions, especially in days before plastic bottles and screw-tops.

  50. Methane emissions from Siberian sinkholes

    @scaddenp

    https://uaf.edu/news/nova-episode-explores-arctic-methane-explosions.php

    https://www.bbc.com/future/article/20201130-climate-change-the-mystery-of-siberias-explosive-craters

    https://www.vice.com/en/article/wx5mmq/the-ground-is-literally-exploding-due-to-climate-change-in-siberia-and-its-going-to-get-worse

    https://www.severe-weather.eu/global-weather/siberia-massive-craters-frozen-ground-permafrost-methane-gas-explosion-rrc/

    Moderator Response:

    [BL] As noted by moderator RH in comment #5, please turn your text into proper links. The web software here does not automatically create links. You can do this when posting a comment by selecting the "insert" tab, selecting the text you want to use for the link, and clicking on the icon that looks like a chain link. Add the URL in the dialog box.

    In addition, please note that the comments policy discourages link-only comments. Specifically:

    No link or picture only. Any link or picture should be accompanied by text summarizing both the content of the link or picture, and showing how it is relevant to the topic of discussion. Failure to do both of these things will result in the comment being considered off topic.

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