4 ms·

Wow. I see - at best - a random walk. A random walk where the noise is about 5 times the amplitude of any signal you might argue is there. I also see the mean

by gd1 11y ago

Wow. I see - at best - a random walk. A random walk where the noise is about 5 times the amplitude of any signal you might argue is there. I also see the mean tailing off the last three years to be lower than it was in '93. What do you see? I certainly don't see the "The Marshall Islands Are Disappearing". Is this some sort of Rorschach test that I'm failing?

cadlin 11y ago
Maybe you're not very good at interpreting data? This might help : http://www.jmu.edu/assessment/wm_library/Analyzing%20&%20Interpreting%20Data.ppt http://www.jmu.edu/assessment/wm_library/Analyzing%20&%20Int...
Mikeb85 11y ago
Look at your data. The last time it trended down significantly there was a major weather event (hint: 1997-1998)... The same major weather event is upon us right now. Anyhow, fit a regression line, and the trend is upward for most parts of the world. Maybe someday we'll return to an ice age, I mean, we were there in some parts of the world 10000 years ago. Right now the data shows we're in a warming cycle. It may be human-caused, it may be forces beyond our understanding (after all, the planet has gone through several heating-cooling cycles), but either way it's happening.
- WillPostForFood 11y ago
  Except NASA says El Nino warming can cause up to an inch of sea level rise due to thermal expansion, so if you see a downtrend in 1097-8 and this year, it is in spite of weather events, not because of it.
  - Mikeb85 11y ago
    Complex systems can have strange behaviour. I'm just looking at data.
  - kaybe 11y ago
    El Nino has changing wind patterns. Wind pushes the ocean water around: It leads to the Eastern Pacific (America) being lower than the West (Asia) normally (surface wind goes west), normally about ~50cm above mean before Asia and about 20cm below mean before America. This changes during El Nino events, when the surface wind changes direction and the water is pushed the other way (~20cm below mean before Asia and 20cm above mean before America). Those values include thermal expansion and stuff. The Marshall islands are more to the Asia side of the Pacific. There is a ~20cm dip in 1998. [1] It fits. [1] http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=g&days=100 http://sealevel.colorado.edu/content/interactive-sea-level-t...
tveita 11y ago
There's some noise, but the trend seems clear to me. The median starts out oscillating around the '1' line, but by 2008 - 2014 it barely touches the line at all. There's a drop from 2014-2016, but it's too early to say if it's temporary like the drop between 1997-1998 (El Niño?) We can say a priori that the sea level is not a random walk. A random walk is boundless - the sea level is not going to suddenly rise 100 meters.
kaybe 11y ago
This comment gives a good smoothing in the interactive data set, it might help: https://news.ycombinator.com/reply?id=10664069&goto=item%3Fid%3D10663326 https://news.ycombinator.com/reply?id=10664069&goto=item%3Fi...

by gd1 11y ago

cadlin 11y ago

Maybe you're not very good at interpreting data? This might help : http://www.jmu.edu/assessment/wm_library/Analyzing%20&%20Interpreting%20Data.ppt http://www.jmu.edu/assessment/wm_library/Analyzing%20&%20Int...

Mikeb85 11y ago

Look at your data. The last time it trended down significantly there was a major weather event (hint: 1997-1998)... The same major weather event is upon us right now. Anyhow, fit a regression line, and the trend is upward for most parts of the world. Maybe someday we'll return to an ice age, I mean, we were there in some parts of the world 10000 years ago. Right now the data shows we're in a warming cycle. It may be human-caused, it may be forces beyond our understanding (after all, the planet has gone through several heating-cooling cycles), but either way it's happening.

WillPostForFood 11y ago
Except NASA says El Nino warming can cause up to an inch of sea level rise due to thermal expansion, so if you see a downtrend in 1097-8 and this year, it is in spite of weather events, not because of it.
- Mikeb85 11y ago
  Complex systems can have strange behaviour. I'm just looking at data.
- kaybe 11y ago
  El Nino has changing wind patterns. Wind pushes the ocean water around: It leads to the Eastern Pacific (America) being lower than the West (Asia) normally (surface wind goes west), normally about ~50cm above mean before Asia and about 20cm below mean before America. This changes during El Nino events, when the surface wind changes direction and the water is pushed the other way (~20cm below mean before Asia and 20cm above mean before America). Those values include thermal expansion and stuff. The Marshall islands are more to the Asia side of the Pacific. There is a ~20cm dip in 1998. [1] It fits. [1] http://sealevel.colorado.edu/content/interactive-sea-level-time-series-wizard?dlat=7&dlon=171&fit=n&smooth=g&days=100 http://sealevel.colorado.edu/content/interactive-sea-level-t...

tveita 11y ago

There's some noise, but the trend seems clear to me. The median starts out oscillating around the '1' line, but by 2008 - 2014 it barely touches the line at all. There's a drop from 2014-2016, but it's too early to say if it's temporary like the drop between 1997-1998 (El Niño?) We can say a priori that the sea level is not a random walk. A random walk is boundless - the sea level is not going to suddenly rise 100 meters.

kaybe 11y ago

This comment gives a good smoothing in the interactive data set, it might help: https://news.ycombinator.com/reply?id=10664069&goto=item%3Fid%3D10663326 https://news.ycombinator.com/reply?id=10664069&goto=item%3Fi...