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The deviation in sea ice extent from previous years is terrifying. I've been watching lines be slightly lower than previous years my whole life but it seems lik

The deviation in sea ice extent from previous years is terrifying. I've been watching lines be slightly lower than previous years my whole life but it seems like the ice loss has accelerated dramatically.

nemo44x 3y ago
Antarctic sea ice extent had been rising from 1979 (when satellite data started) to 2015. It regressed for a few years and then expanded again in 2020 and 2021 and then regressed again. There's a lot of causes of this and there are studies looking at it going back many hundreds and thousands of years, but they aren't as accurate as satellite data. Additionally, different seas in the antarctic have had different behaviors. Some have regressed and some have expanded at different times. https://cp.copernicus.org/articles/18/1729/2022/ https://cp.copernicus.org/articles/18/1729/2022/ > ...changes in atmospheric circulation, wind stress and thermodynamic processes linked to the Southern Annular Mode (SAM) and El Niño–Southern Oscillation (ENSO) >...Thus, projections of future Antarctic sea-ice extent and the associated climate implications are highly uncertain. Point is - we don't know.
- dj_mc_merlin 3y ago
  Seems this was immediately heavily downvoted (I'm not OP). Curious to see what arguments against this stance are.
  - deleted 3y ago
    [deleted]
  - kristopolous 3y ago
    Citing large technical volumes and claiming they say something counter to a consensus, such as https://climate.nasa.gov/vital-signs/ice-sheets/ https://climate.nasa.gov/vital-signs/ice-sheets/ is a classic bluff. For example, it's one of Alex Jones's favorite tactics. I spent a couple minutes on the article in question and it does not agree with the OP. The bluffer in this classic game, however, has already moved on to misappropriating their next large volume. It's easy to toss smoke bombs.
    - dj_mc_merlin 3y ago
      This isn't really a counter argument. It's more of a form of rhetoric argument, which is also what you're accusing GP of.
      - kristopolous 3y ago
        I don't think you get it. Let's say you don't speak, say, Chinese. I make a claim that's in stark disagreement to the general consensus, such as "The Chinese claim their country is an island in the Caribbean north of Jamaica" and then I find a large academic text, in Chinese, and claim that I translated a section of it that supports my argument. What are you going to do? Learn Chinese, read the text, then come back in 4 years and tell me I'm wrong? That's what this game is. You can go and find the quote the OP is using, read the context, and, if you take the time, see it doesn't mean what they claim. It's asymmetrical and either not done in good faith or not worth engaging in.
        dj_mc_merlin 3y ago
        Yes, but you haven't proven this is what GP is doing. You have just asserted it is, without providing further evidence beyond > I spent a couple minutes on the article in question and it does not agree with the OP. which is not very convincing. You might very well be right but it doesn't seem logically consistent to dismiss arguments in this way. We have time to debate anyway.
        kristopolous 3y ago
        Go check the OP replies. I'm under no obligation to further convince you of that which is obvious. Thanks for your time. Have a good afternoon
        dj_mc_merlin 3y ago
        Of course, it's an online forum, no need to engage further if you do not wish to. Have a good day.
  - csnover 3y ago
    Edit: I moved this comment to reply directly to the OP at https://news.ycombinator.com/item?id=37251831 https://news.ycombinator.com/item?id=37251831 since that seems like a better place for it.
    - dj_mc_merlin 3y ago
      This actually seems like a good counter argument.
- elzbardico 3y ago
  [flagged]
  - sonofhans 3y ago
    > “ Please don't comment about the voting on comments. It never does any good, and it makes boring reading.” https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- __alexs 3y ago
  Arctic sea ice has been quite stable for the past 100 years but has recently begun to shrink rapidly. I imagine scientists might be worried that the Antarctic might be about to start seeing a similar change in behaviour.
  - nemo44x 3y ago
    This article is about Antarctic ice.
  - CalRobert 3y ago
    Antarctic sea ice has also begun to shrink rapidly, dramatically so. Check out https://climatereanalyzer.org/clim/seaice/ https://climatereanalyzer.org/clim/seaice/ (you'll need to click "switch hemisphere")
- deleted 3y ago
  [deleted]
- yongjik 3y ago
  > >...Thus, projections of future Antarctic sea-ice extent and the associated climate implications are highly uncertain. > Point is - we don't know. People keep interpreting "we don't know" in the same way a mutual fund information sheet says "past performance does not guarantee future performance," but in reality, "we don't know" is akin to saying "You have a stage three liver cancer and it will likely spread to some other organs, but we don't know yet which organ and when." Some people keep saying "But the doctors can't even tell me what will happen next month! I'm probably fine."
  - nemo44x 3y ago
    You're making a huge leap there. We do know that cancer is a sickness and we actually do know your chances of survival 6 months out, 1 year out, 5 years out, etc. We don't know the day you will die from it but we are certain you will die from it if left untreated. We have lots of empirical data that can be tested, replicated, and stated with a high probability of certainty. We have actual knowledge on this. This is what science is used for - to create actual knowledge. Not informed opinions.
    - yongjik 3y ago
      You are the one making a logical leap. We do know that the Earth's climate is entering conditions never seen during human history. We know how CO2 warms up the Earth. We just don't have a detailed knowledge of exactly how and where it affects weather. The operating assumption must be that things that never happened (or very rarely happened) will start to happen more frequently. You are arguing that as long as climatologists cannot reliably predict any particular disaster, we should assume the climate should be "business as usual." That's not science, that's just refusing to acknowledge the reality.
- burkaman 3y ago
  That paper is quite difficult to interpret for a non-expert, and isn't focused on just sea ice extent. I'm not sure what they mean by "extent", is it a maximum or an average? Here's a link with some graphs that are easier to understand: https://www.climate.gov/news-features/understanding-climate/understanding-climate-antarctic-sea-ice-extent https://www.climate.gov/news-features/understanding-climate/.... The annual maximum follows the trend you describe, while the annual minimum has been more static and decreased substantially in the last few years.
- olddustytrail 3y ago
  Here's the graph of Antarctic minimum: https://www.climate.gov/sites/default/files/styles/full_width_620_original_image/public/2023-03/ClimateDashboard-Antarctic-sea-ice-summer-minimum-graph-20230307-1400px.jpg?itok=qHONdopL https://www.climate.gov/sites/default/files/styles/full_widt...
- csnover 3y ago
  Just based on a cursory examination, you seem to be cherry-picking from your citation and omitting words that appear in that study, like “slightly”, to make it sound as if there was some sort of significant growth of the Antarctic ice sheet since 1979 that is now reverting to some stable state, which is not the case. Looking at the data itself, Antarctic sea ice extent was pretty stable until the past two years, where it has fallen quite dramatically.[0] I think it is reasonable to express some alarm when you’ve gone from a trend of -0.12% per decade, to 16% below the 30-year average, in two years. [0] https://www.ncei.noaa.gov/access/monitoring/snow-and-ice-extent/sea-ice/S/7 https://www.ncei.noaa.gov/access/monitoring/snow-and-ice-ext...
  - nvm0n2 3y ago
    It doesn't follow that it's reasonable to express alarm. Decades of stability followed by sudden change is strong evidence against CO2 being the cause, because growth of that in the atmosphere is a very stable process. It suggests a different cause, which means it's natural, most likely related to undersea volcanism. In which case it's unlikely to be dangerous, unless you think this is some sort of freak event like an asteroid strike. But then you're not talking about climate change.
  - nemo44x 3y ago
    There was a huge burst recently and then a crash. It’s a regression to the mean.

nemo44x 3y ago

Antarctic sea ice extent had been rising from 1979 (when satellite data started) to 2015. It regressed for a few years and then expanded again in 2020 and 2021 and then regressed again. There's a lot of causes of this and there are studies looking at it going back many hundreds and thousands of years, but they aren't as accurate as satellite data. Additionally, different seas in the antarctic have had different behaviors. Some have regressed and some have expanded at different times. https://cp.copernicus.org/articles/18/1729/2022/ https://cp.copernicus.org/articles/18/1729/2022/ > ...changes in atmospheric circulation, wind stress and thermodynamic processes linked to the Southern Annular Mode (SAM) and El Niño–Southern Oscillation (ENSO) >...Thus, projections of future Antarctic sea-ice extent and the associated climate implications are highly uncertain. Point is - we don't know.

dj_mc_merlin 3y ago
Seems this was immediately heavily downvoted (I'm not OP). Curious to see what arguments against this stance are.
- deleted 3y ago
  [deleted]
- kristopolous 3y ago
  Citing large technical volumes and claiming they say something counter to a consensus, such as https://climate.nasa.gov/vital-signs/ice-sheets/ https://climate.nasa.gov/vital-signs/ice-sheets/ is a classic bluff. For example, it's one of Alex Jones's favorite tactics. I spent a couple minutes on the article in question and it does not agree with the OP. The bluffer in this classic game, however, has already moved on to misappropriating their next large volume. It's easy to toss smoke bombs.
  - dj_mc_merlin 3y ago
    This isn't really a counter argument. It's more of a form of rhetoric argument, which is also what you're accusing GP of.
    - kristopolous 3y ago
      I don't think you get it. Let's say you don't speak, say, Chinese. I make a claim that's in stark disagreement to the general consensus, such as "The Chinese claim their country is an island in the Caribbean north of Jamaica" and then I find a large academic text, in Chinese, and claim that I translated a section of it that supports my argument. What are you going to do? Learn Chinese, read the text, then come back in 4 years and tell me I'm wrong? That's what this game is. You can go and find the quote the OP is using, read the context, and, if you take the time, see it doesn't mean what they claim. It's asymmetrical and either not done in good faith or not worth engaging in.
      - dj_mc_merlin 3y ago
        Yes, but you haven't proven this is what GP is doing. You have just asserted it is, without providing further evidence beyond > I spent a couple minutes on the article in question and it does not agree with the OP. which is not very convincing. You might very well be right but it doesn't seem logically consistent to dismiss arguments in this way. We have time to debate anyway.
        kristopolous 3y ago
        Go check the OP replies. I'm under no obligation to further convince you of that which is obvious. Thanks for your time. Have a good afternoon
        dj_mc_merlin 3y ago
        Of course, it's an online forum, no need to engage further if you do not wish to. Have a good day.
- csnover 3y ago
  Edit: I moved this comment to reply directly to the OP at https://news.ycombinator.com/item?id=37251831 https://news.ycombinator.com/item?id=37251831 since that seems like a better place for it.
  - dj_mc_merlin 3y ago
    This actually seems like a good counter argument.
elzbardico 3y ago
[flagged]
- sonofhans 3y ago
  > “ Please don't comment about the voting on comments. It never does any good, and it makes boring reading.” https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
__alexs 3y ago
Arctic sea ice has been quite stable for the past 100 years but has recently begun to shrink rapidly. I imagine scientists might be worried that the Antarctic might be about to start seeing a similar change in behaviour.
- nemo44x 3y ago
  This article is about Antarctic ice.
- CalRobert 3y ago
  Antarctic sea ice has also begun to shrink rapidly, dramatically so. Check out https://climatereanalyzer.org/clim/seaice/ https://climatereanalyzer.org/clim/seaice/ (you'll need to click "switch hemisphere")
deleted 3y ago
[deleted]
yongjik 3y ago
> >...Thus, projections of future Antarctic sea-ice extent and the associated climate implications are highly uncertain. > Point is - we don't know. People keep interpreting "we don't know" in the same way a mutual fund information sheet says "past performance does not guarantee future performance," but in reality, "we don't know" is akin to saying "You have a stage three liver cancer and it will likely spread to some other organs, but we don't know yet which organ and when." Some people keep saying "But the doctors can't even tell me what will happen next month! I'm probably fine."
- nemo44x 3y ago
  You're making a huge leap there. We do know that cancer is a sickness and we actually do know your chances of survival 6 months out, 1 year out, 5 years out, etc. We don't know the day you will die from it but we are certain you will die from it if left untreated. We have lots of empirical data that can be tested, replicated, and stated with a high probability of certainty. We have actual knowledge on this. This is what science is used for - to create actual knowledge. Not informed opinions.
  - yongjik 3y ago
    You are the one making a logical leap. We do know that the Earth's climate is entering conditions never seen during human history. We know how CO2 warms up the Earth. We just don't have a detailed knowledge of exactly how and where it affects weather. The operating assumption must be that things that never happened (or very rarely happened) will start to happen more frequently. You are arguing that as long as climatologists cannot reliably predict any particular disaster, we should assume the climate should be "business as usual." That's not science, that's just refusing to acknowledge the reality.
burkaman 3y ago
That paper is quite difficult to interpret for a non-expert, and isn't focused on just sea ice extent. I'm not sure what they mean by "extent", is it a maximum or an average? Here's a link with some graphs that are easier to understand: https://www.climate.gov/news-features/understanding-climate/understanding-climate-antarctic-sea-ice-extent https://www.climate.gov/news-features/understanding-climate/.... The annual maximum follows the trend you describe, while the annual minimum has been more static and decreased substantially in the last few years.
olddustytrail 3y ago
Here's the graph of Antarctic minimum: https://www.climate.gov/sites/default/files/styles/full_width_620_original_image/public/2023-03/ClimateDashboard-Antarctic-sea-ice-summer-minimum-graph-20230307-1400px.jpg?itok=qHONdopL https://www.climate.gov/sites/default/files/styles/full_widt...
csnover 3y ago
Just based on a cursory examination, you seem to be cherry-picking from your citation and omitting words that appear in that study, like “slightly”, to make it sound as if there was some sort of significant growth of the Antarctic ice sheet since 1979 that is now reverting to some stable state, which is not the case. Looking at the data itself, Antarctic sea ice extent was pretty stable until the past two years, where it has fallen quite dramatically.[0] I think it is reasonable to express some alarm when you’ve gone from a trend of -0.12% per decade, to 16% below the 30-year average, in two years. [0] https://www.ncei.noaa.gov/access/monitoring/snow-and-ice-extent/sea-ice/S/7 https://www.ncei.noaa.gov/access/monitoring/snow-and-ice-ext...
- nvm0n2 3y ago
  It doesn't follow that it's reasonable to express alarm. Decades of stability followed by sudden change is strong evidence against CO2 being the cause, because growth of that in the atmosphere is a very stable process. It suggests a different cause, which means it's natural, most likely related to undersea volcanism. In which case it's unlikely to be dangerous, unless you think this is some sort of freak event like an asteroid strike. But then you're not talking about climate change.
- nemo44x 3y ago
  There was a huge burst recently and then a crash. It’s a regression to the mean.