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Working with LBC

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Trying to produce a static fields for a relatively high resolution x1.2621442, takes a very long time and not feasible on a desktop PC. My question is, can you create a limited region from a grid file first, then create static fields from the smaller limited region grid file?

For example, from -> -> To be exact create_region uses the following:
Name: Antarctic
Type: circle
Point: -72, 165.0
radius: 600000.0 # Meters

While I can create static fields from limited region, I don't know about the consequences of doing so.
Hi zemega, sorry about the slow reply on this topic.

Yes, you might have problems when running the static interpolation on that size of a grid, mainly you might run onto memory issues. You may see that it fails during the bootstrapping. However, as you suggest you can create a region and then run the static interpolation upon that region. This may still take a significant amount of time, but you should see static interpolation move through the bootstrapping and start processing datatiles. For reference, I ran the static interpolation on your region with on the x1.2621442 grid and it took ~75 mins.

Potential problems with running the static interpolation on some regions
This is a good question to ask as there are some pitfalls when running the v7.0 static interpolation on regions; however, this depends on the shape and position of the region. To match dataset pixels to cells, the v7.0 code randomly chooses a cell center of the mesh, calculates the distance of that cell center to the data pixels location and compares that distance with the distances of the cells neighbor. It then chooses the neighbor with the closet distance to the data pixel and repeats the process until the starting cell is closer to the pixel than any of its neighbors.

This approach is great for global meshes, but has some problems with some regions. Specifically regions similar to region produced by the channel method. You can imagine a channel around the earth that is high in latitudes, but doesn't cover the north pole (say 45 - 80 degrees latitude). If you can imagine, the algorithm, depending on where it starts, may find that a cell that lies across the pole to be the closet to a pixel, which would map the wrong value to the wrong cell.

Answering Your Question
This may be more information than you need for your answer, but I figured I'd present the information for those with similar concerns or questions. But to answer your question:

I believe your region will not be subject to the problems discussed above, so you should be safe in running the static interpolation on your region. Great question.

Some recommendations
I recommend that you run the static interpolation on a coarser grid, if you have not already done so. You can than use this static file to modify your Antarctic region as you see fit (I find I need to modify my points file a few times to get the right region). Once you have your Antarctic region looks good for your coarser mesh, then use subset the mesh and run the static interpolation upon the created region. Hopefully this will save you the headache of having the run the static interpolation multiple times as you are selecting your region.

Best of luck!