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I got vector layer that represents height over sea level. Then, I also have different vector layers. Is there any good way of using QGiS or things related to calculate sea level for those points?

Edit:
Those points that are in different layers only have location. They are names of hills, rivers and so forth. What I need is to merge the info of those two layers. So I know how high over sea level the items are.

Edit two; (Sorry not subject that I am strong in) I got line vector layer. With line every 20m of elevation. Over all of Iceland. With about 60.000 points that I need to find hight over sea level on. I dont mind leting the computer work on this but not by hand :)

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What do you mean by calculate sea level? Can you edit your post and explain some more? –  Paul Nov 9 '13 at 0:57

2 Answers 2

I got vector layer that represents height over sea level.

If this vector layer is a point layer, you could use interpolation to create height raster. Then you can sample that raster at any location give by your other layers.

Whether this will lead to acceptable results depends on how your input height data layer looks like - especially how dense the points are.

Update: Since you have lines - isolines - you will need other algorithms to create the height raster. See this question for solutions: Generate raster from isolines

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I got line vector layer. With line every 20m of elevation. Over all of Iceland. With about 60.000 points that I need to find hight over sea level on. I dont mind leting the computer work on this but not by hand :) –  user23802 Nov 10 '13 at 13:43

You need a source of elevation data. A fairly universal source is the Shuttle Radar Topography Mission (SRTM) from 2001(?) which is held by a variety of organisations in different forms. There may be differences in the form of the dataset for land and water. There is some work to get that data out.

Another way of getting a bit of data is to use Google Earth, make a line, then right click on the feature in the legend on the left, choose from the context menu Show elevation. Me thinks Google have loaded up the SRTM data here for our pleasure.

Google Earth Shot

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