Monday, March 29, 2010

Some Questions

Now that I’ve figured out the threshold I’m going to use and I have an easy method to calculate the true area of the glaciers I’m ready to start calculating some numbers but I have a few questions before jumping in and doing so. I also found a great tool for ArcGIS that would more accurately allow me to look at true surface area based off the LiDAR I have. I’m waiting for Dawn and Mark to approve/dissaprove of the installation of it. It won 2nd prize at the 2009 ESRI conference and it’s free so I hope they approve it. You can check it out HERE

  1. 1.I have several choices based off the outlines I got from Andrew Fountain for years to use as the clipping features for my band ratio areas. I need to use a year that is before the start of my analysis and the choices seem to be 1984 or 1970. I should also note that I don’t have outlines for Glisan, ZigZag or Palmer for any years from the stuff I got from Portland. Any ideas of what I should do about this or just leave those glaciers out of the analysis? For 1984 I have White River, Reid, Newton Clark, Elliot and Coe. For 1970 I have those 5 plus the Sandy and Ladd. I’m tempted to use the 1970 outline just because it give me a little more leeway for the large 30x30 resolution landsat and I can look at more glaciers. I’d like to keep my clip outlines all the same year to be consistent across the analysis. Does 1970 sound ok with you?

  1. 2.What glacier outlines should I use for Rainier to clip? My choices are the 1913 outline or the 1995 Nylen outline that I got from Beth. The 1913 would work because it would allow more room but it also may allow some misclassified bandratio non-ice areas because there is so much room in the outline. Do you know of any other earlier outlines I may be able to find to use as a “clip” outline?

Those are my two main questions for now I guess.

1 comment:

Jon Ellinger said...

Could you try using both the 1984 and the 1970 outlines for Mt. Hood? That way we can see how the choice of outline affects the results. Do you have older outlines for any of the glaciers? I've seen rough outlines for Eliot that go way back in time.

If you don't have outlines for all the glaciers then I guess you'll have to skip them. Unless you can create your own 1984 outline using the thresholded Landsat data.

For Mt. Rainier, please use both outlines (1913 and 1994) -- again, to see the differences in the results.
Tuesday, March 30, 2010 - 05:12 AM