Terrain: Mapzen / Tilezen Terrain Tiles, accessed on 7 October 2026 via AWS Open Data.

Underlying terrain source credits and licences, following the official Tilezen/Joerd attribution documentation:

• ArcticDEM: DEM(s) were created from DigitalGlobe, Inc., imagery and funded under National Science Foundation awards 1043681, 1559691, and 1542736.
• Geoscience Australia: © Commonwealth of Australia (Geoscience Australia) 2017. Creative Commons Attribution 4.0 International Licence.
• Austria DGM: © offene Daten Österreichs – Digitales Geländemodell (DGM) Österreich. Creative Commons Namensnennung 3.0 Österreich.
• Canadian Digital Elevation Model: Contains information licensed under the Open Government Licence – Canada.
• EU-DEM: Produced using Copernicus data and information funded by the European Union - EU-DEM layers.
• ETOPO1: U.S. National Oceanic and Atmospheric Administration. DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce. Produced by the NOAA National Geophysical Data Center. Not subject to copyright protection within the United States. NOAA disclaimer.
• INEGI Mexico: Source: INEGI, Continental relief, 2016. Free use of information licence.
• Land Information New Zealand: Copyright 2011 Crown copyright (c) Land Information New Zealand and the New Zealand Government. All rights reserved. Creative Commons Attribution 3.0 New Zealand.
• Kartverket Norway: © Kartverket. Creative Commons Attribution 4.0 International (CC BY 4.0). Provider licence.
• UK Environment Agency: © Environment Agency copyright and/or database right 2015. All rights reserved. Open Government Licence version 3.
• USGS 3DEP (formerly NED), GMTED2010 and SRTM: United States 3DEP (formerly NED) and global GMTED2010 and SRTM terrain data courtesy of the U.S. Geological Survey. USGS credit guidance; USGS standard disclaimer; SRTM distribution policy.

  Joerd records this historical SRTM notice for products distributed outside the United States: “© COPYRIGHT (year of production) BY THE UNITED STATES GOVERNMENT. NO COPYRIGHT CLAIMED UNDER TITLE 17 U.S.C.” The source production year is not supplied with this combined Terrain Tiles raster; the policy’s wording is retained here without assigning a year.

Borders and places: Natural Earth, 1:50 million data. Made with Natural Earth. Public domain; terms of use.

About this terrain

The source relief is resampled, smoothed and aligned to Natural Earth coastlines. Small island places are retained; Antarctica is omitted. Dragging adds and removes local terrain. These alterations are part of this experiment and are not endorsed by the data providers.

World stats estimate this altered model on its full terrain grid. Areas use spherical latitude-band weighting in the map’s Natural Earth I projection. Land created and submerged count sea-level crossings against the original model, rather than total height change. Zero elevation is treated as land.

Highest point is sampled from the altered terrain. Ocean area measures the map area covered by water; Ocean share expresses that area as a percentage. Both include inland water and the area where Antarctica is omitted. These are estimates of this altered map rather than surveyed Earth statistics.