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I am using QGIS. I am aware there is a similar question here but the solution (changing the layer CRS) is not working for me. I cannot change my CRS as I am using information for the entire Asia-Pacific region. Is there another option to create a 1000 km buffer zone from all volcanoes in the region? It is currently projected as geographic coordinates, the default WGS:84.

marked as duplicate by PolyGeo Nov 24 '15 at 22:19

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  • What GIS are you using and which solutions have you tried? Are you working with point data? Please edit your question with this information so that we can assist you. – Conor Sep 8 '13 at 22:58
  • Is your data in a geographic or projected coordinate system? Also, what is the name of the coordinate system of your data? – Conor Sep 8 '13 at 23:09
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The issue is that WGS 84 is a geographic coordinate system vs. a projected coordinate system. When you are telling QGIS that you want a 1000 km buffer, it is interpreting it as a 1000 degree buffer (an impossibly large amount). This is why it is covering your entire screen. To solve your problem you need to project your data into a projected coordinate system, then do your buffer. (See this link for further information.)

Regarding which projection you should use, since you are doing distance buffering, a hemisphere-wide projection that preserves distance would be most appropriate. An azimuthal distance projection seems like it would work for you.

  • I understand that, but the projected coordinate systems appear to only be by state or country not regional, which is where I am having problems.. – lis Sep 8 '13 at 23:28
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    I am sure there are continental ones, ie Lambert Conformal Conic and the like – user681 Sep 8 '13 at 23:32
  • @lis I have edited my answer to address your issue. – Conor Sep 8 '13 at 23:36

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