Table 1 Some relevant USGS NGP products and end-user egress statistics
From: A guide to creating an effective big data management framework
| Â | Â | Files | Size |
|---|---|---|---|
Topographic maps | US Topographic Maps | Â | Â |
 Current | 65,240 | 3.0 TB | |
 Historical | 162,067 | 4.0 TB | |
 Total | 227,307 | 7.0 TB | |
Historical Topographic Map Collection (HTMC) | Â | Â | |
372,515 | 2.0Â TB | ||
GeoTIFF | 183,113 | 1.5Â TB | |
3D elevation program (3DEP) | Lidar Point Cloud (LPC) | Â | Â |
Total | – | 259 TB | |
Digital elevation model (DEM)—current |  |  | |
 2 arc-second | 1,486 | 5.0 GB | |
 1 arc-second | 11,536 | 121.6 GB | |
 1/3 arc-second | 4,414 | 457.3 GB | |
 1 m | 160,362 | 15 TB | |
Digital elevation model (DEM)—historical |  |  | |
 2 arc-second | 2,250 | 5.1 GB | |
 1 arc-second | 17,483 | 145.6 GB | |
 1/3 arc-second | 8,050 | 641.6 GB | |
 1/9 arc-second | 8,345 | 626 GB | |
 Original Product Resolution (OPR) | – | 27 TB | |
Alaska Interferometric Synthetic Aperture Radar (ifsar) | Â | Â | |
 Digital Elevation Model (DEM) | – | 415 GB | |
 Digital Surface Model (DSM) | – | 249 GB | |
 Orthorectified Radar Image (ORI) | – | 3.96 TB | |
Base Maps | Â | Â | |
 US Topo with Imagery Tile Cache | – | 1.57 TB | |
 USGS Hydro Cache | – | 815 MB | |
 USGS Imagery Only Cache | – | 1.21 TB | |
 USGS Shaded Relief Only Cache | – | 276 GB | |
 USGS US Topo Only Cache | – | 854 GB |