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Topographic Maps

Topographic Maps

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Tech & Sources

Software
GDAL, PostgreSQL/PostGIS, MapServer, Apache

Languages
SQL, Bash

Data Sources (one or more):
U.S. Geological Survey (USGS), U.S. Forest Service (USFS), National Elevation Data (NED), National Land Cover Data(NLCD), National Hydrography Data (NHD), Tiger/Line Census, 3D Elevation Program (3DEP), Geographic Names Information Service (GNIS), Open Street Map (OSM), Protected Areas Database v2.1 (PAD), National Interagency Fire Center (NIFC), National Weather Service (NWS), NASA, NOAA, National Wildfire Coordinating Group (NWCG), AirNOW.gov, U.S. Department of Interior (DOI), National Digital Forecast Database (NDFD), European Space Agency (ESA), USAFacts.org, ESRI, Google, Continental Divide Trail Coalition, Appalachian Trail Conservancy (ATC), National Snow and Ice Data Center (NSIDC), PRISM Climate Data Oregon State University, et al, and data collected in the field (trail trace)

Notes

Image: Crater Lake, Oregon, USA

Process:
The above image represents 29 distinct layers created from the noted data sources served by Apache/MapServer WMS service. All data except 3DEP (WMS source) is stored in an enterprise PostgreSQL/PostGIS database. Each layer represents an SQL query in a .map file.

Waterbody Gradient: this custom effect adds a compelling gradient style to all waterbodies. The effect is created using a waterbody polygon, st_straightskeletion, then gdal_grid with specific values for the final raster layer. This is not bathymetry.

Modeled Snow: another custom effect using elevation, slope and aspect fed to an algorithm using st_mapalgebra (callback version). In this case the snowline is set to near 6,200 feet. This is just a style, not an actual climate model.

WMS Resource:
localhost/services/reflect?
   layers=nlcd,modsnow,contours,nhdflowline,nhdwaterbody,nhdline,nhdarea,glacierContours,watergrad,demshade,statePerimeterLabels,states48Label,otherRoads,otherRoadsLabels,mainRoads,rails,airfield,shields,lineAttr,pointAttr,pointAttrLabels,class,states48,trails,trace,osmtrailjct,terminus,mileMarker,llgrid
   &snowline=6200
   &trail_id=1
   &width=3500
   &t_srs=EPSG:3857
   &bbox=-122.30,42.86,-122.115,42.95
   &format=image/png
   &map.scalebar

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