Geography Project (Cat skiing operation)

[char]

For my geography class I need to develop a project which will use the analytical tools in ARCGis. I've decided that siting a cat skiing operation would be a pretty good project. I have a few idea on criteria for siting such an operation but I figure that you guys could help me out a bit, being the endless wells of information that you are.

A few criteria:

• Slope (I figure that a cat skiing operation would need access to a variety of terrain so it could attract a wide customer base.)
• Aspect
• Avy Danger (year round average, I don't know if there is data available for this, anyone?)
• Average snowfall
• Max 24 hour snowfall

[Telenater]

You want a real challenge?

Use ArcGIS to route the cat roads so that they are the shortest distance without exceeing a set slope either side or straight on.
relatively easy to do if your projecting the length of the road onto a plane, but not so straight forward if you get the true distance.


Data that you're likely to need includes DEMs (use the highest accuracy that you can), precipitation (might be hard to find for snow precip, most of what I've seen is water equivalent), Land cover types (tight trees, no trees, wide spaced trees) Landownership. I don't know of any Avy danger stats that are already in a GIS format. Some parts of the US you might be able to get basic info like trigger zone lat lon.

Sounds like a really cool project. Will you be coding anyof it in ArcObjects or is it going to be a onetime processing deal?

[char]

Whoa there buddy, ARCObjects? That must be next weeks class. I'll look into it.

I figure that this will probably be a one time deal. The prof actually said today that he doesn't care if we make up the data, so long as we tell him and our methods are sound. He also said that a routing project is likely to receive a better score than a mere siting project.


I like the road calculation idea. Do cat operations use existing roads or do they cut there own? Also, do they operate on public land or private? Both?

Thanks guys.

[Telenater]

Routing is a far more difficult task to do right than siting.

If you don't already know what ArcObjects is then I think its a safe assumption that you won't be using them for this project unless you're an absolute programming whiz with VB.

I belive most cat operations in the US are on public land. I think they use a combination of existing roads and cutting their own. In most places they probably use existing roads to get through treed areas and then cut their own roads above treeline. But if it's important get solid info from a cat operation, don't take my word on it.

regarding true lengths, very few people even try to provide true on the ground lengths for three dimensional routing. It takes a fair amount of math and generally requires that you make a lot of assumptions based on your DEM resolution. Its actually easier to find the shortest acceptible path using raster calculations than to find the length of the path.

[funkendrenchman]

Originally posted by Telenater

Data that you're likely to need includes DEMs (use the highest accuracy that you can), precipitation (might be hard to find for snow precip, most of what I've seen is water equivalent), Land cover types (tight trees, no trees, wide spaced trees) Landownership. I don't know of any Avy danger stats that are already in a GIS format. Some parts of the US you might be able to get basic info like trigger zone lat lon.

I believe SNOTEL sites report precip and well as SWE. Just google SNOTEL.

[Telenater]

Originally posted by funkendrenchman
I believe SNOTEL sites report precip and well as SWE. Just google SNOTEL.

Yup, they do, but to use SNOTEL data directly off the web you're going to have to do a lot of processing. Its based off of individual sampling sites. There will be too much spatial variability based on topography in any reasonably sized cat skiing area to make an analysis based on SNOTEL data useful as anything other than as a very broad snowfall measure.

[gonzo]

nerds????? NEEERRRRDDDDS!!!! [/ogre]

[Red Baron]

Nerds? C'mon. It's better than "ever shaved your package"...

That's quite a cool project, even if you're going to "be creative" with your dataset.

I'm with Telenater 100% as far as using SNOTEL data; we use it all the time here for single site analysis, but the network is so widely spaced out you'd be hard pressed to find the right data to use.

That said, we do use "basin-wide" percentages to show snowfall averages compared to average in Utah.

Here's a link for any other nerds to use later this year:
ftp://ftp.wcc.nrcs.usda.gov/data/sno...t/ski_west.txt

(PS, if you ever want to piss off a snow surveyor, throw some extra snow on the SNOTEL pillow; that'll really get 'em going...)

[BobMc]

Originally posted by Red Baron
Nerds? C'mon. It's better than "ever shaved your package"...

Hey now! Depends on your perspective.

BobMc

[funkendrenchman]

Aren't all precip sites relatively spread out. Would you just use weighted averages? What else could you do to get the areal average or amounts at specific points which are not measured?

[truth]

Originally posted by Telenater
Routing is a far more difficult task to do right than siting.

I belive most cat operations in the US are on public land. I think they use a combination of existing roads and cutting their own. In most places they probably use existing roads to get through treed areas and then cut their own roads above treeline.

Depending upon whoose land it is (national forest, BLM, mining claims) most ops use existing or multiuse roads below treeline and build snow roads above treeline. The vast majority of which change from year to year depending upon the snowfall, snowpack and the skill of the cat operator.

[The AD]

Originally posted by char
The prof actually said today that he doesn't care if we make up the data, so long as we tell him and our methods are sound.

Don't say you "made up data" in your report. "I estimated certain parameters" has a much nicer ring to it

[char]

Hey, I'm just qouting the prof.

Thanks for the input guys. I'll look into what I can find.

funken- I imagine I could interpolate the data, but I have no idea how to go about that.

I'm trying to set this up so that I'm looking at the whole Washington Cascade Range as potential cat skiing ground and then use ARCGis to find the best spot(s).

If/When I finish the project I'll get back to you. Now to find a few partners interested in this sort of thing.

[nhtele]

As far as Avy data go, you might have a look at

www.avalanchemapping.org
They have data sets for UT and CO, not sure about WA.
By using Spatial Analyst and the buffering wizard you can essentially find the intersection of appropriate slopes and aspects.

When it comes time to present you might think about presenting your data in 3D using ArcScene - a really cool effect.

Are you at Univ. of Washington? Do you like it? I'm considering looking at them for a PhD in Geomorphology/Glaciology.