Pennsylvania • Shaded Relief (USGS 3DEP)

Day 5 (Earth): I created a shaded relief map of Pennsylvania using digital elevation data, which showcases the state’s diverse topography from the Appalachian Mountains to the lower-lying regions. This visualization combines hypsometric tinting with advanced ray-tracing and ambient shading techniques through the rayshader package. It creates a three-dimensional appearance that emphasizes Pennsylvania’s terrain and elevation changes.

Technical Implementation:

• elevatr - R package for accessing elevation data from the USGS 3D Elevation Program (3DEP)
• rayshader - R package for creating advanced 2D and 3D data visualizations with ray-tracing and ambient occlusion
• terra - R package for spatial data analysis and raster processing
• sf - R package for handling spatial vector data and geometric operations
• tigris - R package for accessing TIGER/Line shapefiles from the U.S. Census Bureau
• ggplot2 - R’s powerful data visualization package.
• viridis - R package providing perceptually uniform color scales
• dplyr - R package for data manipulation and transformation

Data Sources:

• Elevation Data: USGS 3D Elevation Program (3DEP) - High-resolution digital elevation model accessed via elevatr package at zoom level 10
• State Boundaries: U.S. Census Bureau TIGER/Line Cartographic Boundary Files - 2023 State Boundaries

Coordinate Reference System:

• EPSG:2272 (Pennsylvania State Plane South, NAD83, US Feet) for accurate local representation