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greglindahl

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.

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We'll try the BOM then, that goes back to '93:

http://www.bom.gov.au/ntc/IDO70052/IDO70052SLI.shtml

Try any source you like. Show me something hard to back up "The Marshall Islands are Disappearing"

The chart you linked shows sea levels are rising, but that doesn't seem to match the argument you're making?

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?

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.

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.

Complex systems can have strange behaviour. I'm just looking at data.

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-t...

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.

This comment gives a good smoothing in the interactive data set, it might help:

https://news.ycombinator.com/reply?id=10664069&goto=item%3Fi...

from the chart "Maximum recorded level of 2.405 metres at 0430 hours 18/02/2011"

I'm really unclear on how this chart shows rising given the max was in 2011?

A good question, if all you looked at is just one chart. Next, read the scientific literature about how people interpret the chart. In this case, you appear to be confusing climate and weather? If you're looking at an effect on the average of something over decades, the fact that the maximum was 5 years ago is not that significant.

"In this case, you appear to be confusing climate and weather?"

No, I'm just looking at a suggested chart and seeing nothing

Is there a chart that goes farther back with the raw values like this one?

Ah. If you're only looking at the chart, and not the huge body of science that goes with it, then pointing out another chart with a longer baseline isn't going to help you much.

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?

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.

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-t... does less drastic smoothing, to show a bit more detail.

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.

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.

Most GW people are fooled by randomness. It's just this generations version of how people are going to destroy the world. Every generation needs something to freak out about.

Here's all you have to know about sea level rise...

When land in Ohio is as expensive than land in NYC, we have a big fucking sea level problem. Until then, all the smart and wealthy people in the world aren't concerned and neither should you be.

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