Yukon Analysis Constructing Base Map

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Base Maps

Simple Base Map

The simple base map is constructed out of 2 simple raster data sources, these data sources are pipelines that are read into WorldView using pipelines and integrated on the PYXIS DERM to produce one coherent map.

Data Sources Used

  • World.topo.bathy.200408.3x21600x21600.A1.tif
  • YukonMosaic90mNoClouds.tif

Process

  • We start with a low resolution image provided from the World.topo.bathy datasource.

LowResBaseMap 0 1.jpg

  • However due to the low resolution of this data source it is going to be difficult to perform an indepth analysis which will yield highly acurate and meaningful results. Therefore it it necessary to upload a higher resolution data source of the specific area in which we are interested.


  • Open YukonMosaic90mNoClouds.tif in WorldView.

HighResNoContext.jpg


  • Clearly this high resolution map of the Yukon would make an ideal base map to perform our analysis on. However because the edges are masked out and clearly there is data that has been lost. It is possible to run into situations where the data we want to analyze extends off the edge of the map that data is present for, as indicated in the image below.


HighResNoContext Issues.jpg


  • From the areas highlighted it is difficult to interpret this data without some form of context applied to the data. To help gain a better understanding of the data highlighted above we integrate the high resolution Yukon Mosaic map with a lower resolution World.topo map to provide context to the areas that have been filtered out of the Yukon Map. After integration our base map looks like.


IntegratedBaseMap 0.jpg


  • In our integrated base map you can see that the areas previously masked out in the high res map of the Yukon Territory are now filled in with data from our lower resolution map.


This will be the base map which will be used for performing analysis on the Yukon Territory in Yukon Analysis

Total time to construct base map: 6 minutes.


Complex Base Map

This base map was generated from data found at the Yukon Geomatics department's ftp site. It was done only to demonstrate how quick and easy it is to generate a highly detailed highly accurate base map using WorldView.

Data Sources Used

Raster Imagery

  • World.topo.bathy.200408.3x21600x21600.A1.tif
  • YukonMosaic90mNoClouds.tif


Vectors

  • Yukon_polygon.shp
  • roads_line.shp
  • rivers_line.shp
  • contours_line.shp

Elevations

  • world_2minute.g98


Process

Each image is going to show one step in making the map I will document the changes in the image from step to step

Start with a low resolution raster image.

LowResBaseMap 0 1.jpg


Open a vector file Yukon_polygon.shp outlining the area we're interested in.

LowResBaseMap 1.jpg


Open higher resolution raster imagery file YukonMosaic90mNoClouds.tif to fill in the area we're interested in making a map for.

LowResBaseMap 2.jpg


Open a vector file roads_line.shp describing the road network in the Yukon

LowResBaseMap 3.jpg


Open a vector file rivers_line.shp describing the river network in the Yukon

LowResBaseMap 4.jpg


Open a vector file contours_line.shp describing the river network in the Yukon

NOTE: I also hid the library and the properties by unchecking the check boxes at the top of the screen to see more of the image

LowResContours.jpg


Zoom in on the contours to see them at a medium resolution rather then a low resolution as show above.

MediumResBaseMapExample.jpg


Zoomed in to Higher resolution then shown above and opened an elevation data source

ElevationFlat.jpg


Titled the map to better examine the full base map with an elevation data source open

ElevationTitled.jpg


Total time to construct base map: 15 minutes.