{"id": 1207178, "name": "Terrain Ruggedness Index 100m (Nunn and Puga 2012)", "unit": "hundreds of metres of elevation difference", "description": "This is the Terrain Ruggedness Index originally devised by Riley, DeGloria, and Elliot (1999) to quantify topographic heterogeneity in wildlife habitats providing concealment for preys and lookout posts. The source of elevation data is GTOPO30 (US Geological Survey, 1996), a global elevation data set developed through a collaborative international effort led by staff at the US Geological Survey's Center for Earth Resources Observation and Science (EROS). Elevations in GTOPO30 are regularly spaced at 30 arc-seconds across the entire surface of the Earth on a map using a geographic projection, so the sea-level surface distance between two adjacent grid points on a meridian is half a nautical mile or, equivalently, 926 metres. After calculating the Terrain Ruggedness Index for each point on the grid, we average across all grid cells in the country not covered by water to obtain the average terrain ruggedness of the country's land area. Since the sea-level surface that corresponds to a 30 by 30 arcsecond cell varies in proportion to the cosine of its latitude, when calculating the average terrain ruggedness \u2014 or the average of any other variable \u2014 for each country, we weigh each cell by its latitude-varying sea-level surface. We assign land to countries \u2014 for this and other variables \u2014 using digital boundary data based on the fifth edition of the Digital Chart of the World (US National Imagery and Mapping Agency, 2000), which we have updated to reflect 2000 country boundaries using information from the International Organization for Standardization ISO 3166 Maintenance Agency and other sources. We exclude areas covered by permanent inland water area features contained in the same edition of the Digital Chart of the World. The units for the terrain ruggedness index correspond to the units used to measure elevation differences. In our calculation, ruggedness is measured in hundreds of metres of elevation difference for grid points 30 arc-seconds (926 metres on the equator or any meridian) apart.", "createdAt": "2026-03-06T11:06:30.000Z", "updatedAt": "2026-03-06T11:06:30.000Z", "coverage": "", "timespan": "1996-1996", "datasetId": 7589, "shortUnit": "m", "columnOrder": 0, "shortName": "terrain_ruggedness_index_100m__nunn_and_puga_2012", "catalogPath": "grapher/geography/2018-04-15/terrain_ruggedness_index__nunn_and_puga__2012/terrain_ruggedness_index__nunn_and_puga__2012#terrain_ruggedness_index_100m__nunn_and_puga_2012", "type": "float", "datasetName": "Terrain Ruggedness Index - Nunn and Puga (2012)", "datasetVersion": "2018-04-15", "nonRedistributable": false, "display": {"unit": "metres of elevation difference", "shortUnit": "m", "conversionFactor": 100}, "schemaVersion": 1, "presentation": {}, "source": {"id": 31310, "name": "Nunn and Puga (2012)", "dataPublishedBy": "Nunn, Nathan, and Diego Puga, \u2018\u2018Ruggedness: The Blessing of Bad Geography in Africa,\u2019\u2019 Review of Economics and Statistics, 94, no. 1 (2012), 20\u201336.", "dataPublisherSource": "", "link": "https://diegopuga.org/data/rugged/", "retrievedDate": "2018-04-15", "additionalInfo": ""}, "dimensions": {"years": {"values": [{"id": 1996}]}, "entities": {"values": [{"id": 15, "name": "Afghanistan", "code": "AFG"}, {"id": 16, "name": "Albania", "code": "ALB"}, {"id": 17, "name": "Algeria", "code": "DZA"}, {"id": 246, "name": "American Samoa", "code": "ASM"}, {"id": 18, "name": "Andorra", "code": "AND"}, {"id": 19, "name": "Angola", "code": "AGO"}, {"id": 228, "name": "Anguilla", "code": "AIA"}, {"id": 20, "name": "Antigua and Barbuda", "code": "ATG"}, {"id": 21, "name": "Argentina", "code": "ARG"}, {"id": 22, "name": "Armenia", "code": "ARM"}, {"id": 219, "name": "Aruba", "code": "ABW"}, {"id": 23, "name": "Australia", "code": "AUS"}, {"id": 24, "name": "Austria", "code": "AUT"}, {"id": 25, "name": "Azerbaijan", "code": "AZE"}, {"id": 26, "name": "Bahamas", "code": "BHS"}, {"id": 27, "name": "Bahrain", "code": "BHR"}, {"id": 28, "name": "Bangladesh", "code": "BGD"}, {"id": 29, "name": "Barbados", "code": "BRB"}, {"id": 30, "name": "Belarus", "code": "BLR"}, {"id": 4, "name": "Belgium", "code": "BEL"}, {"id": 31, "name": "Belize", "code": "BLZ"}, {"id": 32, "name": "Benin", "code": "BEN"}, {"id": 194, "name": "Bermuda", "code": "BMU"}, {"id": 33, "name": "Bhutan", "code": "BTN"}, {"id": 34, "name": "Bolivia", "code": "BOL"}, {"id": 35, "name": "Bosnia and Herzegovina", "code": "BIH"}, {"id": 36, "name": "Botswana", "code": "BWA"}, {"id": 37, "name": "Brazil", "code": "BRA"}, {"id": 351, "name": "British Indian Ocean Territory", "code": "IOT"}, {"id": 196, "name": "British Virgin Islands", "code": "VGB"}, {"id": 38, "name": "Brunei", "code": "BRN"}, {"id": 39, "name": "Bulgaria", "code": "BGR"}, {"id": 40, "name": "Burkina Faso", "code": "BFA"}, {"id": 41, "name": "Burundi", "code": "BDI"}, {"id": 42, "name": "Cambodia", "code": "KHM"}, {"id": 43, "name": "Cameroon", "code": "CMR"}, {"id": 44, "name": "Canada", "code": "CAN"}, {"id": 45, "name": "Cape Verde", "code": "CPV"}, {"id": 197, "name": "Cayman Islands", "code": "CYM"}, {"id": 174, "name": "Central African Republic", "code": "CAF"}, {"id": 173, "name": "Chad", "code": "TCD"}, {"id": 172, "name": "Chile", "code": "CHL"}, {"id": 171, "name": "China", "code": "CHN"}, {"id": 247, "name": "Christmas Island", "code": "CXR"}, {"id": 263, "name": "Cocos Islands", "code": "CCK"}, {"id": 170, "name": "Colombia", "code": "COL"}, {"id": 169, "name": "Comoros", "code": "COM"}, {"id": 168, "name": "Congo", "code": "COG"}, {"id": 199, "name": "Cook Islands", "code": "COK"}, {"id": 166, "name": "Costa Rica", "code": "CRI"}, {"id": 143, "name": "Cote d'Ivoire", "code": "CIV"}, {"id": 165, "name": "Croatia", "code": "HRV"}, {"id": 164, "name": "Cuba", "code": "CUB"}, {"id": 163, "name": "Cyprus", "code": "CYP"}, {"id": 162, "name": "Czechia", "code": "CZE"}, {"id": 167, "name": "Democratic Republic of Congo", "code": "COD"}, {"id": 161, "name": "Denmark", "code": "DNK"}, {"id": 154, "name": "Djibouti", "code": "DJI"}, {"id": 200, "name": "Dominica", "code": "DMA"}, {"id": 160, "name": "Dominican Republic", "code": "DOM"}, {"id": 225, "name": "East Timor", "code": "TLS"}, {"id": 201, "name": "Ecuador", "code": "ECU"}, {"id": 65, "name": "Egypt", "code": "EGY"}, {"id": 259, "name": "El Salvador", "code": "SLV"}, {"id": 159, "name": "Equatorial Guinea", "code": "GNQ"}, {"id": 157, "name": "Eritrea", "code": "ERI"}, {"id": 156, "name": "Estonia", "code": "EST"}, {"id": 78, "name": "Eswatini", "code": "SWZ"}, {"id": 158, "name": "Ethiopia", "code": "ETH"}, {"id": 249, "name": "Falkland Islands", "code": "FLK"}, {"id": 250, "name": "Faroe Islands", "code": "FRO"}, {"id": 202, "name": "Fiji", "code": "FJI"}, {"id": 155, "name": "Finland", "code": "FIN"}, {"id": 3, "name": "France", "code": "FRA"}, {"id": 253, "name": "French Guiana", "code": "GUF"}, {"id": 203, "name": "French Polynesia", "code": "PYF"}, {"id": 153, "name": "Gabon", "code": "GAB"}, {"id": 151, "name": "Gambia", "code": "GMB"}, {"id": 152, "name": "Georgia", "code": "GEO"}, {"id": 6, "name": "Germany", "code": "DEU"}, {"id": 150, "name": "Ghana", "code": "GHA"}, {"id": 251, "name": "Gibraltar", "code": "GIB"}, {"id": 149, "name": "Greece", "code": "GRC"}, {"id": 205, "name": "Greenland", "code": "GRL"}, {"id": 206, "name": "Grenada", "code": "GRD"}, {"id": 252, "name": "Guadeloupe", "code": "GLP"}, {"id": 254, "name": "Guam", "code": "GUM"}, {"id": 148, "name": "Guatemala", "code": "GTM"}, {"id": 147, "name": "Guinea", "code": "GIN"}, {"id": 94, "name": "Guinea-Bissau", "code": "GNB"}, {"id": 146, "name": "Guyana", "code": "GUY"}, {"id": 145, "name": "Haiti", "code": "HTI"}, {"id": 139, "name": "Honduras", "code": "HND"}, {"id": 144, "name": "Hong Kong", "code": "HKG"}, {"id": 138, "name": "Hungary", "code": "HUN"}, {"id": 207, "name": "Iceland", "code": "ISL"}, {"id": 137, "name": "India", "code": "IND"}, {"id": 136, "name": "Indonesia", "code": "IDN"}, {"id": 135, "name": "Iran", "code": "IRN"}, {"id": 134, "name": "Iraq", "code": "IRQ"}, {"id": 2, "name": "Ireland", "code": "IRL"}, {"id": 133, "name": "Israel", "code": "ISR"}, {"id": 8, "name": "Italy", "code": "ITA"}, {"id": 132, "name": "Jamaica", "code": "JAM"}, {"id": 14, "name": "Japan", "code": "JPN"}, {"id": 130, "name": "Jordan", "code": "JOR"}, {"id": 131, "name": "Kazakhstan", "code": "KAZ"}, {"id": 129, "name": "Kenya", "code": "KEN"}, {"id": 204, "name": "Kiribati", "code": "KIR"}, {"id": 208, "name": "Kuwait", "code": "KWT"}, {"id": 126, "name": "Kyrgyzstan", "code": "KGZ"}, {"id": 125, "name": "Laos", "code": "LAO"}, {"id": 122, "name": "Latvia", "code": "LVA"}, {"id": 124, "name": "Lebanon", "code": "LBN"}, {"id": 123, "name": "Lesotho", "code": "LSO"}, {"id": 121, "name": "Liberia", "code": "LBR"}, {"id": 120, "name": "Libya", "code": "LBY"}, {"id": 209, "name": "Liechtenstein", "code": "LIE"}, {"id": 119, "name": "Lithuania", "code": "LTU"}, {"id": 210, "name": "Luxembourg", "code": "LUX"}, {"id": 262, "name": "Macao", "code": "MAC"}, {"id": 118, "name": "Madagascar", "code": "MDG"}, {"id": 117, "name": "Malawi", "code": "MWI"}, {"id": 116, "name": "Malaysia", "code": "MYS"}, {"id": 211, "name": "Maldives", "code": "MDV"}, {"id": 115, "name": "Mali", "code": "MLI"}, {"id": 212, "name": "Malta", "code": "MLT"}, {"id": 223, "name": "Marshall Islands", "code": "MHL"}, {"id": 284, "name": "Martinique", "code": "MTQ"}, {"id": 114, "name": "Mauritania", "code": "MRT"}, {"id": 213, "name": "Mauritius", "code": "MUS"}, {"id": 193, "name": "Mayotte", "code": "MYT"}, {"id": 113, "name": "Mexico", "code": "MEX"}, {"id": 222, "name": "Micronesia (country)", "code": "FSM"}, {"id": 111, "name": "Moldova", "code": "MDA"}, {"id": 214, "name": "Monaco", "code": "MCO"}, {"id": 112, "name": "Mongolia", "code": "MNG"}, {"id": 216, "name": "Montserrat", "code": "MSR"}, {"id": 110, "name": "Morocco", "code": "MAR"}, {"id": 109, "name": "Mozambique", "code": "MOZ"}, {"id": 142, "name": "Myanmar", "code": "MMR"}, {"id": 108, "name": "Namibia", "code": "NAM"}, {"id": 218, "name": "Nauru", "code": "NRU"}, {"id": 107, "name": "Nepal", "code": "NPL"}, {"id": 5, "name": "Netherlands", "code": "NLD"}, {"id": 362, "name": "Netherlands Antilles", "code": "ANT"}, {"id": 220, "name": "New Caledonia", "code": "NCL"}, {"id": 106, "name": "New Zealand", "code": "NZL"}, {"id": 105, "name": "Nicaragua", "code": "NIC"}, {"id": 104, "name": "Niger", "code": "NER"}, {"id": 103, "name": "Nigeria", "code": "NGA"}, {"id": 261, "name": "Niue", "code": "NIU"}, {"id": 285, "name": "Norfolk Island", "code": "NFK"}, {"id": 128, "name": "North Korea", "code": "PRK"}, {"id": 66, "name": "North Macedonia", "code": "MKD"}, {"id": 266, "name": "Northern Mariana Islands", "code": "MNP"}, {"id": 102, "name": "Norway", "code": "NOR"}, {"id": 217, "name": "Oman", "code": "OMN"}, {"id": 101, "name": "Pakistan", "code": "PAK"}, {"id": 224, "name": "Palau", "code": "PLW"}, {"id": 140, "name": "Palestine", "code": "PSE"}, {"id": 100, "name": "Panama", "code": "PAN"}, {"id": 99, "name": "Papua New Guinea", "code": "PNG"}, {"id": 98, "name": "Paraguay", "code": "PRY"}, {"id": 97, "name": "Peru", "code": "PER"}, {"id": 96, "name": "Philippines", "code": "PHL"}, {"id": 286, "name": "Pitcairn", "code": "PCN"}, {"id": 11, "name": "Poland", "code": "POL"}, {"id": 95, "name": "Portugal", "code": "PRT"}, {"id": 93, "name": "Puerto Rico", "code": "PRI"}, {"id": 226, "name": "Qatar", "code": "QAT"}, {"id": 245, "name": "Reunion", "code": "REU"}, {"id": 92, "name": "Romania", "code": "ROU"}, {"id": 12, "name": "Russia", "code": "RUS"}, {"id": 91, "name": "Rwanda", "code": "RWA"}, {"id": 260, "name": "Saint Helena", "code": "SHN"}, {"id": 227, "name": "Saint Kitts and Nevis", "code": "KNA"}, {"id": 229, "name": "Saint Lucia", "code": "LCA"}, {"id": 353, "name": "Saint Pierre and Miquelon", "code": "SPM"}, {"id": 230, "name": "Saint Vincent and the Grenadines", "code": "VCT"}, {"id": 239, "name": "Samoa", "code": "WSM"}, {"id": 231, "name": "San Marino", "code": "SMR"}, {"id": 232, "name": "Sao Tome and Principe", "code": "STP"}, {"id": 90, "name": "Saudi Arabia", "code": "SAU"}, {"id": 89, "name": "Senegal", "code": "SEN"}, {"id": 88, "name": "Serbia", "code": "SRB"}, {"id": 233, "name": "Seychelles", "code": "SYC"}, {"id": 87, "name": "Sierra Leone", "code": "SLE"}, {"id": 86, "name": "Singapore", "code": "SGP"}, {"id": 85, "name": "Slovakia", "code": "SVK"}, {"id": 83, "name": "Slovenia", "code": "SVN"}, {"id": 195, "name": "Solomon Islands", "code": "SLB"}, {"id": 82, "name": "Somalia", "code": "SOM"}, {"id": 81, "name": "South Africa", "code": "ZAF"}, {"id": 127, "name": "South Korea", "code": "KOR"}, {"id": 9, "name": "Spain", "code": "ESP"}, {"id": 141, "name": "Sri Lanka", "code": "LKA"}, {"id": 79, "name": "Sudan", "code": "SDN"}, {"id": 234, "name": "Suriname", "code": "SUR"}, {"id": 298, "name": "Svalbard and Jan Mayen", "code": "SJM"}, {"id": 10, "name": "Sweden", "code": "SWE"}, {"id": 7, "name": "Switzerland", "code": "CHE"}, {"id": 77, "name": "Syria", "code": "SYR"}, {"id": 198, "name": "Taiwan", "code": "TWN"}, {"id": 76, "name": "Tajikistan", "code": "TJK"}, {"id": 64, "name": "Tanzania", "code": "TZA"}, {"id": 75, "name": "Thailand", "code": "THA"}, {"id": 74, "name": "Togo", "code": "TGO"}, {"id": 287, "name": "Tokelau", "code": "TKL"}, {"id": 235, "name": "Tonga", "code": "TON"}, {"id": 73, "name": "Trinidad and Tobago", "code": "TTO"}, {"id": 71, "name": "Tunisia", "code": "TUN"}, {"id": 70, "name": "Turkey", "code": "TUR"}, {"id": 69, "name": "Turkmenistan", "code": "TKM"}, {"id": 236, "name": "Turks and Caicos Islands", "code": "TCA"}, {"id": 237, "name": "Tuvalu", "code": "TUV"}, {"id": 68, "name": "Uganda", "code": "UGA"}, {"id": 67, "name": "Ukraine", "code": "UKR"}, {"id": 72, "name": "United Arab Emirates", "code": "ARE"}, {"id": 1, "name": "United Kingdom", "code": "GBR"}, {"id": 13, "name": "United States", "code": "USA"}, {"id": 354, "name": "United States Minor Outlying Islands", "code": "UMI"}, {"id": 256, "name": "United States Virgin Islands", "code": "VIR"}, {"id": 63, "name": "Uruguay", "code": "URY"}, {"id": 62, "name": "Uzbekistan", "code": "UZB"}, {"id": 221, "name": "Vanuatu", "code": "VUT"}, {"id": 257, "name": "Vatican", "code": "VAT"}, {"id": 238, "name": "Venezuela", "code": "VEN"}, {"id": 84, "name": "Vietnam", "code": "VNM"}, {"id": 255, "name": "Wallis and Futuna", "code": "WLF"}, {"id": 248, "name": "Western Sahara", "code": "ESH"}, {"id": 61, "name": "Yemen", "code": "YEM"}, {"id": 60, "name": "Zambia", "code": "ZMB"}, {"id": 80, "name": "Zimbabwe", "code": "ZWE"}]}}, "origins": []}