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But has there actually been sea level rise? If the ice is melting where is the water?



So far a large portion of the ice melting is sea ice. Because that was already floating and thus displacing water it doesn't actually impact sea level. That's why people always talk about Greenland and Antarctica, two landmasses with huge amounts of ice on them (often kilometers deep). When their ice melts (and it is melting, just slower) you see notable changes in sea levels. This will also accelerate when there's less sea ice around the land keeping things cool



I firmly believe in climate change and global warming.

I do have a question though. The graph presented starts in 1880 and rises linearly from then, with no correlation to a graph of CO2 levels, which had far more exponential growth between 1880 - 2010s, until recently.

As I understand it, the mini-ice age finished in the 1800s. And started in the 14th century.

So, is this actual evidence? There doesn't seem to be any visible acceleration from what was always happening pre-global warming. And can be blamed on the mini-ice age finishing.

Most worryingly is that page, from scientists, doesn't even address that obvious objection. It briefly mentions sea levels have risen from the 1880s, but doesn't at all address that eyeballing the graph it seems quite obviously linear.

Even more misleading is the graph someone else has linked which starts in the 1990s and doesn't show the rest of the data.


If you try looking at the actual numbers or sketching rough tangent lines, you'll see that your "eyeballing" is misleading you. The graph is not at all linear -- the slope in recent decades is several times steeper than at the beginning of the time interval, as the accompanying caption says.

Perhaps you're looking at the graph on a phone screen, which compresses the scale and de-exaggerates the changes?


Zoom in and pan around. You'll notice it is not linear.

Look at the slope of 1900 to 1950. Then look at the slope of 1970 to 2020. Are you telling me that's the same slope?


It's interesting to see a nearly linear trend as far back as the data goes (1880). Do you know of any sources to see how that trend might've looked going even further back in time?


Well, 1880 is right after the industrial revolution. Unluckily we only started keeping good records after we kicked changes into a higher gear. This page has one graph that goes back further [1] (and a bunch of other interesting graphs).

On geological scales we are at or near a high point [2] after the previous ice age

1: https://research.csiro.au/slrwavescoast/sea-level/sea-level-...

2: https://www.e-education.psu.edu/earth107/node/1506


Have an industrial revolution -> get rich enough to care about science -> realize we should track the environment -> start to take measurements and writing them down.

The only other path that leads to environmental tracking is if some order of monks developed an obscure interest in it in pre-industrial times.


https://en.wikipedia.org/wiki/Past_sea_level

The ice age had a big impact on sea levels, estimates of 100m lower than it is today


Linear? The rise is more than twice as much between 1980-2020 as 1880 to 1920.


More specifically, 2.5 according to the post

> The global mean water level in the ocean rose by 0.14 inches (3.6 millimeters) per year from 2006–2015, which was 2.5 times the average rate of 0.06 inches (1.4 millimeters) per year throughout most of the twentieth century.





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