What climate change is not

Discussion in 'Earth Science' started by billvon, Jan 28, 2020.

  1. billvon Valued Senior Member

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    21,635

    Yes. It might even make the Sahara uninhabitable. Do you think humanity will be doomed if the Sahara becomes uninhabitable?
    Millions of years.

    You posted how there's a place in Canada that hit a record high of 21C. Let's say we see catastrophic, runaway climate change and that place sees highs of 26C once a year. Could you survive there?
     
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  3. Quantum Quack Life's a tease... Valued Senior Member

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    I do understand your point... however you are being way too optimistic and also way to sarcastic...
    Runaway climate change is estimated to increase average temperatures up to 12 deg C.
    Note the word "average".

    To achieve that increase in averages, assuming that that is the limit of average warming hypothesized, what do you think the average max temp would be?
    You could have an average of 0 deg C and yet suffer heat waves of 70deg C...
    Here in Australia we may have a national average of about 22 deg C yet heat waves maxing out at 48 deg C are becoming more common. It is not unreasonable to anticipate an average max of 50+deg C to be the new norm in a couple of years. Now remember we are talking about an average max, which means the deviations may be higher. Terminal peak heat events could be considerably higher.
    Also you have to consider what the effects of ocean warming would be in a runaway climate change scenario on evaporation rates etc..
    Example: a 35 deg C wet bulb temp and humans can not survive with out artificial assistance. (Death in 30 minutes or so)
    It has already occurred in an unpopulated region of Western Australia (1st time) a few years ago if I recall correctly.
    You only need a peak heat event to last 30 minutes or so to generate an effected region animal termination event. ( complete wipe out)


    The main point I wished to make is that it is often ignored how an average is calculated and when it comes to terminal events the use of an average can inspire a false sense of optimism, there fore inaction.

    Note: At all times typical anomalous situation can and often do arise. That is to say regardless of trends there will always be anomalies. Trending towards life limits means that those anomalies become more life threatening. IOW our safety margin is reducing.
     
    Last edited: Jan 29, 2020
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  5. billvon Valued Senior Member

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    Nope. 12F - 7C. (IPCC worst case prediction.)
    No, you couldn't. Today the hottest temperature extremes on the planet are around 56C (Death Valley, 1913.) In the future, you will see a similar range with a new baseline. So your new once-a-century extreme in Death Valley might be 63C.

    Meanwhile, most places will have average (and minimum, and maximum) temperatures like they are now, just 6C higher.

    Yes, you will see peaks of 50C by the middle of the century. By 2100 you might see peaks of 55C.
    Yes, you do. And that _has_ been considered.
    And this thread is to remind you that the opposite will happen if you take such an approach.

    Let's say you see a friend of yours start smoking. You want him to stop - for his own good. You tell him "you will be dead by tomorrow if you keep smoking!" The next day he is alive and questions your wisdom.

    "Yeah, well . . . if you don't stop smoking within a week you'll be dead!" A week later he is alive and questions your wisdom.
    "Yeah, well . . . if you don't stop smoking within a month you'll be dead!" A month later he is alive and questions your wisdom.
    "Yeah, well . . . if you don't stop smoking within a year you'll be dead!" A year later he is alive - and decides you are completely deranged, and decides to never listen to you again.

    Does that help? (rhetorical question)

    Likewise, let's say a couple years go by. And despite your claims above, 50+C temps do not become "the new norm." You do not see frequent "animal termination events." People in Australia do not die of heatstroke en masse. People will stop listening to you - and by extension, stop taking climate change seriously. Because those alarmists are always wrong.
     
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  7. Quantum Quack Life's a tease... Valued Senior Member

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    If i am not mistaken the IPCC report fails to take into account accelerated human generated CO2 inputs. It presumes a steady CO2 input with out reduction. However the CO2 input is in fact increasing.
    What predictions do they make about CO2 levels in the years 2020-2100? (rhetorical but worth researching IMO)

    Recall my point about Human nature and dependency on fossil fuels.
     
  8. Quantum Quack Life's a tease... Valued Senior Member

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    one of the reasons they do not die en masse is because they make use of artificially cooled habitats. With out air conditioning the situation would be vastly different.
    The key difference is that the habitats would have to become sustainable and self sufficient.
    It is inevitable that larger city sized habitats be developed if the human race is to avoid the extinction threshold. IMO
     
  9. billvon Valued Senior Member

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    21,635
    Nope. The latest IPCC report considers 40 scenarios, from depression to boom economy, from all-hands-on-deck renewables and nuclear to all fossil. The A1F1 is the most pessimistic and presumes that the GWP will grow by a factor of 10 by 2100 and almost all new energy will come from oil, coal and natural gas.
    Yes. A1F1 predicts an exponential increase in CO2 emissions - going from 15 gigatons a year (2020) to 35 gigatons a year (2100.)
    In the worst case, >1000ppm.
    No, they really don't. Having A/C to get you through a heat wave is not the same as having a sealed, self sufficient biome.
    Alarmist nonsense brought about by watching too many movies.
     
  10. Quantum Quack Life's a tease... Valued Senior Member

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    23,328
    Thanks for setting me straight on the IPCC report....
    I sincerely hope that they and you are correct in their predictions of human survive=ability
     
  11. Jeeves Valued Senior Member

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    5,089
    To what? How fast? Animals that evolved in a forest will not suddenly make the necessary changes to tundra - even if there were a food supply for the herbivores. Forests will not suddenly grow above the tree line, just because it's become warmer and wetter: growing a forest takes hundreds of years; establishing its balanced interdependent ecosystem takes thousands.
    When the forest burns, even the animals that are able to run or fly away (a small minority) will have no place to go. It takes generations to adapt - if there is a new food supply, if there is suitable cover, shelter, habitat - and only weeks to starve to death when there isn't.
    Something will adapt - but it's more likely to be worms and fungi than elk and white pine.
    Raccoons and rats will make it, too - they'll move into the vacated human habitations. Grizzlies and caribou can't.
    Of course, what animals do make it through the upheaval period will fall victim to the millions of displaced, indigent, crazed humans pushing north and inland from uninhabitable areas, shooting and looting all the way.
     
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  12. Quantum Quack Life's a tease... Valued Senior Member

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    billvon,
    Do you have a link to the IPCC A1F1 scenario that details premises for that scenario and details of predictions etc...
    Googling so far for me has proved frustrating...
     
  13. billvon Valued Senior Member

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    21,635
  14. Quantum Quack Life's a tease... Valued Senior Member

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    608 pages ! No wonder Trump pulled the USA out of the Paris accord...given his interest in reading and comprehension.
    I've seen this document before but have yet to find in among it's 608 pages any specific section that deals with the premises of A1F1 that are assumed to be present.
     
  15. billvon Valued Senior Member

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    21,635
    Really? Here are a few pointers:

    P. 24, Table SPM-2 gives energy intensities, populations, coal and renewable energy usage for each of the scenarios.

    P.44: Figure TS-6 illustrates the CO2 emissions across the SRES scenarios in relation to each of the three main scenario driving forces - global population, gross world product and primary energy requirements. The general tendencies across the driving forces are consistent with the underlying literature. All else being equal, the higher future global populations, higher gross world product, or higher primary energy requirements would be associated with higher emissions.

    P.44: Figure TS-7 illustrates the range of CO2 emissions of the SRES scenarios against the background of all the IS92 scenarios and other emissions scenarios from the literature documented in the SRES scenario database (blue shaded area). The range of future emissions is very large so that the highest scenarios envisage a tenfold increase of global emissions by 2100 while the lowest have emissions lower than today.

    Note that this is a summary of Working Group III of the IPCC; it in general does not contain the source material. (If you were intimidated by 608 pages, the source material is going to be WAY larger.)
     
  16. Quantum Quack Life's a tease... Valued Senior Member

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    Thanks... do they present a plain English worded summary conclusion for scenario A1F1. A summary that the average politician can understand?
    Most politicians I would imagine would file this document and go to lunch...and never refer to this document or the IPCC again for fear of embarrassing them selves.
    Little wonder there is a lack of climate change action ...
     
    Last edited: Jan 30, 2020
  17. Quantum Quack Life's a tease... Valued Senior Member

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    Within the A1F1 scenario there is a point where CO2 emissions become irrelevant surely?
    My reasoning: Once the ocean evaporation feedback loop is established CO2 plays a relatively small role.
     
  18. billvon Valued Senior Member

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    21,635
    Nope. CO2 already plays a small role compared to water vapor. However, since it prevents re-radiation in a different band, the results will always be additive.
     
  19. exchemist Valued Senior Member

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    I believe I have also read that water vapour acts as an amplifier for the effect of increased CO2. If more CO2 blocks more radiation in the CO2 bands of the IR spectrum, this causes a rise in temperature, whereupon the average vapour pressure of water in the atmosphere will go up, increasing the blocking by the water bands of the IR spectrum as well.
     
  20. billvon Valued Senior Member

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    21,635
    Yes. And that has two effects. On the day side, cloud formation reduces the planet's albedo and results in cooling. On the night side, cloud formation increases IR retention and results in warming. That's why increasing water vapor does not necessarily increase warming. Or, as NASA puts it, "as the climate begins to warm, the atmosphere reorganizes itself in ways that could either amplify or mitigate the original input of energy that initiated the climate change."

    Which effect will be more pronounced? Very hard to say. Clouds tend to form earlier in the day with increasing relative humidity, cooling the sunward side. But relative humidity will not always increase as the planet warms. Low level clouds in warmer atmospheres tend to be "darker" and reflect less light, resulting in warming (compared to cold low-level clouds.) But high altitude rain clouds (i.e anvil clouds and the like) become _more_ reflective, because they are higher in the atmosphere and have a higher albedo due to their smooth upper boundary.
     
  21. iceaura Valued Senior Member

    Messages:
    30,994
    No, it doesn't.
    The effects are not predicted to be linear.
    A thousand fold increase in wildfire would make Australia uninhabitable by humans - likewise several other regions currently home to many millions of people. The consequences of that would hardly be limited to 25,000 deaths.
    Your dismissal of the high end of the range of legitimate and data supported possibilities is optimistic - justifiable, but optimistic.
    You are posting middle and low range predictions, best case scenarios, as if they were certain. They are not. There is a small but non-zero probability, for example, that the unprecedented rate of change under AGW will touch off the "methane bomb" (feedback fed dissolution of clathrates in shallow water and release of methane from permafrost), the consequent regional temperature spikes outright killing most land mammals over forty pounds on the planet. That's what a pessimistic take on the data and theory would look like.
    But it can, and dramatically, if the extra water does not condense into the right kinds of clouds. Also if the night warming (concentrated as predicted in the winter nights at higher latitudes) overpowers the day cooling (the simplest consequence of Newton's Law of Cooling). The night warming would almost certainly have more dramatic ecological effects than a plateau in the day warming, on biological grounds. And the methane release would happen regardless.

    Again: counting on such uncertain and probably variable feedback effects to bail us out is not pessimism.
     
    Last edited: Feb 2, 2020
  22. iceaura Valued Senior Member

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    30,994
    Under the catastrophic possibilities it would see highs of 40C or more several times a year, and the permafrost would melt over very large regions (releasing methane too rapidly to degrade) - then burn. The humans would have to leave, at least temporarily.
     
  23. Quantum Quack Life's a tease... Valued Senior Member

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    The interesting thing about this comment is that it is actually happening right now to a rather noticeable extent here in Melbourne Australia.
    Two days ago we had the tail end of yet another severe heat wave, that was ended by a rain front and cool change.
    By the time we got to about 11 pm, 4 or so hours after sunset the ambient temperature was climbing noticeably by what felt like about 3 -5 deg C

    My personal living space increased in temperature by about that much as well. A number of locals also commented the following day that it was quite obviously what they consider to be very strange weather. Not only was it extremely humid it was actually hotter at midnight than it was at say 8 pm. This appears to be an entirely new characteristic for Melbourne weather.

    The other thing I wanted to mention was concerning the IPCC report and it's hypothesize scenarios.
    1. They appear to be underestimating the current situation quite dramatically. Possibly due to the the time delay between data collection and report publication.
    2. They offer no probability assessment that their scenario especially A1F1 is indeed the worst case scenario. Ie. What is the probability that the A1F1 scenario is indeed the worst case scenario.
    3. The report is loaded with political considerations to prevent being perceived as alarmist, fearful that to be seen as such it would lessen it's impact.
    4. The report appears to be overly politically conservative thus optimistic.
    5. It is more or less impossible for the average politician to read nor comprehend it's ramifications. People generally need to test their beliefs for themselves and not rely only on expert opinion that is clouded in overly sophisticated language

    The average person in the street is able to experience climate change first hand and requires no report to confirm it's reality. The report delivered in this manner only confuses people and diminishes credibility.
    People generally speaking no longer need to rely on science to tell them that the climate is in serious trouble. They can experience it first hand.
    I haven't read anything that changes my position, basically because I have personally been experiencing dramatic evidence of rapidly deteriorating climate change for 3 years now. To me, the trend is accelerating by many orders faster than predicted by the IPCC.
    • For the first time in 60 years I have had to live in a hazardous smoke haze over 3 consecutive days/nights.
    • Watch 10 million hectares of forest go up in smoke due to wild fires.
    • Fire induced weather systems are being reported in the public realm for the first time.
    • Noting that wild fires are still burning in numerous locations, with our nations capital currently under threat.
    • Dealt with multiple and extreme heat wave conditions.
    • Thunderstorm asthma phenomena previously unheard of, has a hotline to call...
    • Noting that Bureau of Meteorology here reported that for all months of the year 2019 except one (January 2018) were above average maximums by up to 10 degrees C (?) and that the average temperature nation wide was one of the hottest on record.
    • There appears to have been what I would consider a significant uptick in climate change events. Locally and internationally over the course of 2019.
    The actual data is not yet fully compiled for 2019 and the last IPCC report may very well be obsolete and be so in quite dramatic ways.
     

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