Digital Elevations and Digital Orthophoto fields for Mary Jane Ski Resort

Doug Nychka email: nychka "at" ucar "dot" edu

These data form the basis for a extended example using the  fields package for fitting and manipulating curves and surfaces. Refer to the poster, presented at the

Joint Statistical Meetings 2007 for more details on the statistics. The three data components for  this example are located in the WinterPark Mary Jane Ski resort in Colorado and centered around the Super Gauge lift and Riflesight notch ski trial.

Mary Jane Project

The Mary Jane Project (MJP) is a web based guide for the primary ungroomed trails at Winter Park/Mary Jane ski resort. This page provides some quantitative analysis of one run that is part of the MJP.
We would like to acknowledge Allie Nychka from MJP for sharing her broad knowledge on the ski area.

• Motivation
• Guide to run
• Some other work

Data sets

The R datasets and supporting functions are contained in the R binary format file RifleSight.rda and can be obtained from the data directory http://image.ucar.edu/public/Data . (just download this file -- don't let your browser try to display it!)

• Digitial elevation model (DEM) on a 146X196 grid. Elevations  in meters with an approximate grid spacing of 10m.  R data set name is RifleDEM.  This image  was extracted  from a  larger  DEM  that  covers  Winter  Park and  Berthoud  Pass. 

• Digital orthophoto  on a  1155X2003 grid.  Range of grey levels is 5 to 254. R dataset name is RifleI.  Detailed  meta data  provided with  the download  describes the  process and  accuracy of this  image.  The raw image is in tiff format. This was converted to pnm format  and then read into R using the pixmap package.  RifleE is a simple bilinear interpolation of the DEM elevations to the finer image grid created in fields using interp.surface.grid

• Riflesight trail. Using the locator function a skiing run  was input begining at the top of the Super gauge lift, dropping down Sluice Box, continuing under the lift to Riflesight, emptying out on Feebleminded to finish at Super Gauge lift.  RifleI is matrixwith 400 lon/lat locations describing the run and rifle.trail.elev are the interpolated elevations in meters. See the  Trail Map for what skiers typically use to navigate. 

Both image datasets were obtained through the USGS seamless data distribution service. These images are in standard R image list format with components  x  the grid values for longitude,  y the grid for latitudes and z a matrix of values.

Additional components are

• two.colors, MJ.colors:  Useful color table functions for converting grey scale from white to green. 
• fig3.RifleSight: R function  for  perspective figure of image with ski run superimposed.
• trail.degrees: Estimated slope in degrees of the run based on the DEM's and spatial analysis.
• fig4.RifleSight: R function  for image plot of photo with slopes of run and elevation contours
• fields.style: Some default sizes for characters and colors for the figures

fig3.RifleSight	fig4.RifleSight (Ski run from  Lower left to upper right)

More detailed data analysis including Kriging using R and fields

DISCLAIMER:

The data sets, software and related content in and linked to these pages are intended for scientific and mathematical research. The authors do not guarantee the correctness of the data, software or companion text. Please see the UCAR Terms of Use listed below.