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Six Sigma Deviation for Antarctic Sea Ice

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Re: Six Sigma Deviation for Antarctic Sea Ice

#11

Post by cozzyd »

harperlee wrote: post #7
kuhewa wrote: post #3

It's clearly a signal of ongoing warming, but the assumption of a Gaussian probability distribution of annual ice extent- something we only have a few tens of years of data to estimate - seems peculiar.

I’m not a statistician, but I’ve read somewhere the argument that the gaussian is the distribution that assumes the least about its data (just that there’s a mean and non-infinite variance) so it is typically safe to use when you know little about the real distribution. (I’m just commenting to compel someone to correct me and expand on this subthread really :) )

In this case, as each day is highly correlated to the previous one, it is safe to say that the distribution of daily sea ice variation is probably not Gaussian? (Though obviously, this is very bad...)

Re: Six Sigma Deviation for Antarctic Sea Ice

#13

Post by 11235813213455 »

hotpotamus wrote: post #10
rf15 wrote: post #5

Earlier quoted context omitted.

The fun thing is, we cannot recognise this kind of danger. Our regular animalistic detection mechanism cannot be triggered by this, so we're kind of aware but nothing in us tells us to get away from the problem. Even as you write this, you probably don't truly believe that this could very well be the end. For once the slowly boiled frog thing is actually true.

It seems a bit like dying of a radiation overdose - a lethal exposure can take just moments, and you will go on as though nothing happened for a time, but the damage is done and irreversible.

like cigarettes, another dumb behavior of humans

Re: Six Sigma Deviation for Antarctic Sea Ice

#15

Post by 11235813213455 »

rf15 wrote: post #5
junon wrote: post #2

So we're fucked at this point, and nobody is saying anything about it. Don't Look Up was right. We're dumb idiots of a species.

The fun thing is, we cannot recognise this kind of danger. Our regular animalistic detection mechanism cannot be triggered by this, so we're kind of aware but nothing in us tells us to get away from the problem. Even as you write this, you probably don't truly believe that this could very well be the end. For once the slowly boiled frog thing is actually true.

over 20 years I completely recognized a warming, and I'm doing my best (no car, minimal consumption/spending, CO2eq footprint about 5% of average person in Western Europe), not many people are doing this, but there are plently benefits, not just environmental

Re: Six Sigma Deviation for Antarctic Sea Ice

#16

Post by joe__f »

kmmlng wrote: post #9
harperlee wrote: post #7

Earlier quoted context omitted.

I’m not a statistician, but I’ve read somewhere the argument that the gaussian is the distribution that assumes the least about its data (just that there’s a mean and non-infinite variance) so it is typically safe to use when you know little about the real distribution. (I’m just commenting to compel someone to correct me and expand on this subthread really :) )

Maybe you can make an argument that, in the absence of any information, your best bet is assuming a Gaussian distributon, but it definitely is not safe to assume so. Your data might not be symmetrically or even unimodally distributed and making these assumption can lead to completely wrong conclusions.

If you know that your data has a well-defined mean and standard deviation but you know nothing else about it then you start with a Gaussian distribution. This isn't an assumption. The Gaussian distribution has the highest entropy and hence encodes the least information possible about the data. Then as you learn more about your data, you would update this distribution using Bayes' theorem. This could give rise to skew or multiple maxima.

Re: Six Sigma Deviation for Antarctic Sea Ice

#18

Post by roflyear »

11235813213455 wrote: post #12

Where are those persons saying that with global warming Antarctica would actually get cooler?

It is incredibly easy to bash something, very hard to come up with your own ideas.

To show this, reader, try to do a small experiment yourself - something your interested in - but make it really, really small. Can be testing products you use often to see which is the best for you.

It is REALLY hard! And it's extremely easy for people to pick it apart. "Oh, you know more than the guys who wrote the standards?" "I've been using that for years, you're just using it wrong" "Here's a picture of me doing xyz it works fine"

They spent two seconds, you almost certainly spent days and days on your really small test.

This is why you won't see people back up these claims. They didn't spend time or effort getting there, and they won't spend that time or effort backing them up.

Re: Six Sigma Deviation for Antarctic Sea Ice

#20

Post by evandijk70 »

cozzyd wrote: post #11
harperlee wrote: post #7

Earlier quoted context omitted.

I’m not a statistician, but I’ve read somewhere the argument that the gaussian is the distribution that assumes the least about its data (just that there’s a mean and non-infinite variance) so it is typically safe to use when you know little about the real distribution. (I’m just commenting to compel someone to correct me and expand on this subthread really :) )

In this case, as each day is highly correlated to the previous one, it is safe to say that the distribution of daily sea ice variation is probably not Gaussian? (Though obviously, this is very bad...)

The comparison is between ice extent measurements at the same date, at differing years, so the day-to-day correlation is not the relevant metric here, but the year-to-year correlation, which should be very low.
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