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Comment by unsigner | Hacker News Reader

Some of the pictures show signs of warming (although in one of the text descriptions it's attributed to planting of trees), but there's virtually no sea level rise evident?

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The global average sea level is only estimated to have risen about 20 cm (8 inches) since 1880, so it wouldn't really be noticeable in a photograph, especially on steep coasts like Norway's. Whether the photograph was taken at high vs. low tide would make a bigger difference in most cases.

The land level in that part of the world has been rising for the past 100 years, counteracting most changes in sea levels:

https://en.wikipedia.org/wiki/Post-glacial_rebound

Also, more trees might relate to stricter environmental laws (you can't simply take an axe and chop a random tree nowadays) and more advanced and energy efficient heating sources that use biomass briquettes, electricity and gas instead of tree logs from the nearby thicket.

Interesting. The bit that I found most noticeable in the then/now comparison was that people in the past really did not like trees :)

Every bit of human habitation was surrounded by open areas denuded of trees. It actually looked unpleasant and sterile to see the lack of trees near everything man-made. Roads, fields, home...no trees anywhere in the vicinity.

A lot of the difference in vegetation is due to climate change. I'm Norwegian and born in the beginning of October, which was first snow at the time. Now it never snows in October. You have to wait late November or early December. That sort of thing makes a lot of difference to plants.

> Every bit of human habitation was surrounded by open areas denuded of trees.

I theorize that is due to the nearby trees all being used for firewood.

Land owners can generally chop down trees as they wish; with some exceptions, which mostly don't apply in these photos. I think there are three main reasons for the increase in woodland: 1. Less cultivated land; including less land used for grazing (eg. by sheep). 2. Other sources of heating (mostly electricity, some oil, and still some wood, but usually not taken from just outside the door; there is very little use of gas in Norway). 3. Milder climate has raised the tree line. Which of these is most significant probably varies.

You can chop down trees in Norway.

However, trees don't necessarily grow unaided in many of the spots on those pictures. Here's a village I know: http://www.winnem.com/Assets/images/frambergkirkesaether.gif shows lots of trees, a century ago there were none there. They were planted in a big campaign around 1950-1970, in places where no tree could grow alone but a dozen together might grow up and shelter each other if tended a bit. All the schoolchildren planted and tended trees.

Global sea level has risen less than a foot in the past 100 years. Although in environments like this, I would assume isostatic rebound (https://en.wikipedia.org/wiki/Post-glacial_rebound) would play a large role in apparent local sea level changes.

Look at the ground that is covered by water it's clearly tidal shore there are patches of water everywhere.

The rise of see level can be seen pretty clearly in photo no. 6.

You can't be sure that isn't just because the tide is higher. The land now covered by water looked like tideland in the older picture as well.

It's almost certainly the tide. I'm familiar with the area around Torghatten. The high tide/low tide difference there can be ~2 meters, more than enough to explain all the variation in sealevel.

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