8 ms·

Marshall Islands sea level, unchanged for 20 years: http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=

by gd1 11y ago

Marshall Islands sea level, unchanged for 20 years: http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=n&days=60 http://sealevel.colorado.edu/content/interactive-sea-level-t... No one denies the science more than alarmists.

kaybe 11y ago
Hm, to me it looks as if there was a slight upwards trend in the data. Some fitting would have to go on to see if that's true; however, most of the time, fitting by approximating by hand is not so bad. Look at the smoothed data too, it's more obvious there. Also, mind that the scale is in cm and numbers given for sea level rise up to now is in the mm range. We can argue about the clear drop in 2014. And I wonder what happened in 1998. Good source, thank you! edit: Stopped wondering about 1998, it's clearly a strong El Niño signal, and the theory fits as well. Thus, it will probably go back up after next year.
- ctdonath 11y ago
  I applied a polynomial trend line to the data: seems there is a 7.5cm rise over 23 years, but most of that was in the first half and has tapered off and may actually be about to head down. I'd like to see longer-term data. Recurring issue: climate changes. Sea levels change. Land altitudes change. Overlapping cycles interact to great effect covering hours & millennia. And when you're talking about all of these happening in regards to someplace that is no more than 2 meters above "sea level", with nearly a meter of tidal variation daily, it's not unreasonable to conclude "living on the edge of survivability isn't a good choice".
  - kaybe 11y ago
    Sadly, it isn't a choice in many cases.
    - ctdonath 11y ago
      I'd like to see a polite HN discussion about this notion. To wit: in light of a looming existential crisis where circumstantial (mostly financial) difficulties are pitted against prospects of death/destruction, should one be resigned to one's "fate" vs "do anything necessary to move".
greglindahl 11y ago
What smoothing are you recommending, so that we can see that it's unchanged? Hard to see anything in the raw chart. Edit: as you can see below, what I'm contesting is the assertion that it's unchanged.
- gd1 11y ago
  The article claims that it has increased by a foot, which is 30 centimeters: " Changing global trade winds have raised sea levels in the South Pacific about a foot over the past 30 years" What smoothing do you recommend I apply, so that I can see that?
  - burkaman 11y ago
    That graph pretty clearly shows 10 or 15 cm over the last 20 years. I wish I could see the data for 30 years but it doesn't seem impossible that there was a 15 cm rise in those 10 years.
    - logfromblammo 11y ago
      http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=g&days=7300 http://sealevel.colorado.edu/content/interactive-sea-level-t... shows about a 9 cm increase over 20 years. http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=g&days=1095 http://sealevel.colorado.edu/content/interactive-sea-level-t... does less drastic smoothing, to show a bit more detail.
  - kaybe 11y ago
    Maybe that refers to the maxima, which are in the same order of magnitude? Temporary flooding is also described in the article, with the main issue of destroying freshwater supplies and trees. But you're right, that phrasing is a bit weird.
  - greglindahl 11y ago
    While its fun to make fun of the non-scientific article, I'm actually probing at your claim that it's unchanged. You cited evidence, but it doesn't support your claim.
strictnein 11y ago
And the Maldives, supposedly in a similar situation, have been "disappearing" since the early-mid 1800s (and probably earlier). https://pbs.twimg.com/media/CVGSWCvUEAAF4pR?format=png&name=large https://pbs.twimg.com/media/CVGSWCvUEAAF4pR?format=png&name=...
davesque 11y ago
I don't know how you're reading that chart, but it's pretty clearly trending up, unless you're only looking at the past year or so of data points.
ocschwar 11y ago
The data might be noisy, but what is decidedly not noisy is the intrusion of sea water into the groundwater on those islands. These people used to keep vegetable gardens. Now they have to raise them and rely on rainwater tow after them. On these atoms you can see lots of palm tree stumps where the rising salinity killed them off one by one.
Mikeb85 11y ago
http://sealevel.colorado.edu/content/map-sea-level-trends http://sealevel.colorado.edu/content/map-sea-level-trends
ajkjk 11y ago
Really hard to not take you for a crackpot. You: * initially call everyone science-denying alarmists * ignore all the responses that point out that there is trend in the data you linked. * respond only to the reply that gives you the benefit of the doubt ('what smoothing do you recommend so we can see it's unchanged.') by switching datasets and trying to make the same point again (unable to defend it in with first source?) * make a claim of your own ('it's unchanged'), but switch to a different, easier-to-defend claim when contested ('it's not a foot, like the original article claims') So do you actually believe it's unchanged, or are you irrationally dead-set on disagreeing with the article? Can't take you seriously like this.
- gd1 11y ago
  'Crackpot' is a several thousand word article on how climate change is submerging the Marshall Islands when all the hard data shows that sea level has done fuck all except bounce around for 23 years. But sure, yeah, I'm a crackpot.
- gd1 11y ago
  By the way, you will note in my initial source that the final point in the dataset is level with the initial point (slightly below). So it is, in fact, unchanged. You can quibble about smoothing methods, how to fit a regression, etc., but that is the literal english definition of 'unchanged'. Is that defended enough for you? Right now the sea level in the Marshall Islands is roughly where it was 23 years ago. That would be UNCHANGED.
  - ajkjk 11y ago
    You ignored my point entirely. I agree with you that the current sea level is about where it was 23 years ago. I don't agree with you that the graph you linked isn't trending upwards. Obviously if you have a sinusoid that slowly trends up (where the yearly delta is << the (max-min) periodic variation), it's going to oscillate in such a way that a point-in-time view of it might see lower values than the average. That's what sinusoids do. (If it's not obvious to you that the trend, rather than the current value, is the interesting data, then this whole discussion is a waste of time.) So now that we've gotten that out of the way: I'm arguing that you're doing a really bad job of convincing anyone because of your hostility to rational questions and discussion on the subject. I'm doing this a) to inform you, in case it wasn't obvious to you (and it seems like it wasn't) and b) because it's fun to point these things out; Hacker News seems to often enjoy meta-discussions about arguments.

by gd1 11y ago

kaybe 11y ago

Hm, to me it looks as if there was a slight upwards trend in the data. Some fitting would have to go on to see if that's true; however, most of the time, fitting by approximating by hand is not so bad. Look at the smoothed data too, it's more obvious there. Also, mind that the scale is in cm and numbers given for sea level rise up to now is in the mm range. We can argue about the clear drop in 2014. And I wonder what happened in 1998. Good source, thank you! edit: Stopped wondering about 1998, it's clearly a strong El Niño signal, and the theory fits as well. Thus, it will probably go back up after next year.

ctdonath 11y ago
I applied a polynomial trend line to the data: seems there is a 7.5cm rise over 23 years, but most of that was in the first half and has tapered off and may actually be about to head down. I'd like to see longer-term data. Recurring issue: climate changes. Sea levels change. Land altitudes change. Overlapping cycles interact to great effect covering hours & millennia. And when you're talking about all of these happening in regards to someplace that is no more than 2 meters above "sea level", with nearly a meter of tidal variation daily, it's not unreasonable to conclude "living on the edge of survivability isn't a good choice".
- kaybe 11y ago
  Sadly, it isn't a choice in many cases.
  - ctdonath 11y ago
    I'd like to see a polite HN discussion about this notion. To wit: in light of a looming existential crisis where circumstantial (mostly financial) difficulties are pitted against prospects of death/destruction, should one be resigned to one's "fate" vs "do anything necessary to move".

greglindahl 11y ago

What smoothing are you recommending, so that we can see that it's unchanged? Hard to see anything in the raw chart. Edit: as you can see below, what I'm contesting is the assertion that it's unchanged.

gd1 11y ago
The article claims that it has increased by a foot, which is 30 centimeters: " Changing global trade winds have raised sea levels in the South Pacific about a foot over the past 30 years" What smoothing do you recommend I apply, so that I can see that?
- burkaman 11y ago
  That graph pretty clearly shows 10 or 15 cm over the last 20 years. I wish I could see the data for 30 years but it doesn't seem impossible that there was a 15 cm rise in those 10 years.
  - logfromblammo 11y ago
    http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=g&days=7300 http://sealevel.colorado.edu/content/interactive-sea-level-t... shows about a 9 cm increase over 20 years. http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=g&days=1095 http://sealevel.colorado.edu/content/interactive-sea-level-t... does less drastic smoothing, to show a bit more detail.
- kaybe 11y ago
  Maybe that refers to the maxima, which are in the same order of magnitude? Temporary flooding is also described in the article, with the main issue of destroying freshwater supplies and trees. But you're right, that phrasing is a bit weird.
- greglindahl 11y ago
  While its fun to make fun of the non-scientific article, I'm actually probing at your claim that it's unchanged. You cited evidence, but it doesn't support your claim.

strictnein 11y ago

And the Maldives, supposedly in a similar situation, have been "disappearing" since the early-mid 1800s (and probably earlier). https://pbs.twimg.com/media/CVGSWCvUEAAF4pR?format=png&name=large https://pbs.twimg.com/media/CVGSWCvUEAAF4pR?format=png&name=...

davesque 11y ago

I don't know how you're reading that chart, but it's pretty clearly trending up, unless you're only looking at the past year or so of data points.

ocschwar 11y ago

The data might be noisy, but what is decidedly not noisy is the intrusion of sea water into the groundwater on those islands. These people used to keep vegetable gardens. Now they have to raise them and rely on rainwater tow after them. On these atoms you can see lots of palm tree stumps where the rising salinity killed them off one by one.

Mikeb85 11y ago

http://sealevel.colorado.edu/content/map-sea-level-trends http://sealevel.colorado.edu/content/map-sea-level-trends

ajkjk 11y ago

Really hard to not take you for a crackpot. You: * initially call everyone science-denying alarmists * ignore all the responses that point out that there is trend in the data you linked. * respond only to the reply that gives you the benefit of the doubt ('what smoothing do you recommend so we can see it's unchanged.') by switching datasets and trying to make the same point again (unable to defend it in with first source?) * make a claim of your own ('it's unchanged'), but switch to a different, easier-to-defend claim when contested ('it's not a foot, like the original article claims') So do you actually believe it's unchanged, or are you irrationally dead-set on disagreeing with the article? Can't take you seriously like this.

gd1 11y ago
'Crackpot' is a several thousand word article on how climate change is submerging the Marshall Islands when all the hard data shows that sea level has done fuck all except bounce around for 23 years. But sure, yeah, I'm a crackpot.
gd1 11y ago
By the way, you will note in my initial source that the final point in the dataset is level with the initial point (slightly below). So it is, in fact, unchanged. You can quibble about smoothing methods, how to fit a regression, etc., but that is the literal english definition of 'unchanged'. Is that defended enough for you? Right now the sea level in the Marshall Islands is roughly where it was 23 years ago. That would be UNCHANGED.
- ajkjk 11y ago
  You ignored my point entirely. I agree with you that the current sea level is about where it was 23 years ago. I don't agree with you that the graph you linked isn't trending upwards. Obviously if you have a sinusoid that slowly trends up (where the yearly delta is << the (max-min) periodic variation), it's going to oscillate in such a way that a point-in-time view of it might see lower values than the average. That's what sinusoids do. (If it's not obvious to you that the trend, rather than the current value, is the interesting data, then this whole discussion is a waste of time.) So now that we've gotten that out of the way: I'm arguing that you're doing a really bad job of convincing anyone because of your hostility to rational questions and discussion on the subject. I'm doing this a) to inform you, in case it wasn't obvious to you (and it seems like it wasn't) and b) because it's fun to point these things out; Hacker News seems to often enjoy meta-discussions about arguments.