First Pass: Terrain Skeleton

• Track Log Data (white flow lines are from original 10 meter USGS DEM)
  

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Setting the magnetic declination on a compass is a critical step in accurate measurement of bearings that can be translated to map or survey. As the location of the magnetic north pole is constantly moving, the magnetic declination reported on older topographic maps or compass housings are probably out of date. Current declination values for a single point, or for large regions can be found on the NOAA sites:

• single point
• global maps

These resources are helpful, but a current, detailed (state-level) map of magnetic declination would be interesting.

 
Input File Format (see attached CSV file)

   start stop       species transect block transect.length     notes
  

 
Premise:
A generic press-quality plotting system for GRASS, based on GMT. Still a ways to go.

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Premise:
We need some randomly selected areas for performing a vegetation survey. Two possible approaches are given: random selection of grid cells from a 7x7 grid superimposed over the region of interest, and random generation of 100x100 meter blocks which meet certain criteria on how close they can be from each other and the edges of the region. The region and grid files are attached at the bottom of this page.

 
Premise:
Supervised classification of 2005 NAIP imagery (1 meter resolution) into 3 classes (grass, tree, shade), by the SMAP[1-3] algorithm. Tree heights are small compared to horizontal extent, and therefore "shadow" pixels can probably be interpreted as "tree" pixels. Field verification will be needed to check actual percent coverage of classes, and fractionation of tree species within the "tree" pixel class. Still looking up the specific date/time the source imagery was taken. Since the shadows appear to be falling north-ward, the photo was probably taken in the morning. The color of the grass suggests that it was probably summer. In these conditions there should be no shading of this region by local terrain features.

• dylan's blog
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