World 
Map references World, Time Zones 
Area total: 510.072 million sq km 
land: 148.94 million sq km 
water: 361.132 million sq km 
note : 70.8% of the world's surface is water, 29.2% is land 
Land boundaries the land boundaries in the world total 251,480.24 km (not counting shared boundaries twice) 
Coastline 356,000 km 
Maritime claims contiguous zone: 24 nm claimed by most but can vary 
continental shelf: 200-m depth claimed by most or to depth of exploitation, others claim 200 nm or to the edge of the continental margin 
exclusive fishing zone : 200 nm claimed by most but can vary 
exclusive economic zone: 200 nm claimed by most but can vary 
territorial sea: 12 nm claimed by most but can vary 
note: boundary situations with neighboring states prevent many countries from extending their fishing or economic zones to a full 200 nm; 43 nations and other areas that are landlocked include Afghanistan, Andorra, Armenia, Austria, Azerbaijan, Belarus, Bhutan, Bolivia, Botswana, Burkina Faso, Burundi, Central African Republic, Chad, Czech Republic, Ethiopia, Holy See (Vatican City), Hungary, Kazakstan, Kyrgyzstan, Laos, Lesotho, Liechtenstein, Luxembourg, Malawi, Mali, Moldova, Mongolia, Nepal, Niger, Paraguay, Rwanda, San Marino, Slovakia, Swaziland, Switzerland, Tajikistan, The Former Yugoslav Republic of Macedonia, Turkmenistan, Uganda, Uzbekistan, West Bank, Zambia, Zimbabwe
Climate two large areas of polar climates separated by two rather narrow temperate zones from a wide equatorial band of tropical to subtropical climates 
Terrain the greatest ocean depth is the Marianas Trench at 10,924 m in the Pacific Ocean 
Elevation extremes lowest point: Dead Sea -408 m 
highest point: Mount Everest 8,848 m 
Natural resources the rapid using up of nonrenewable mineral resources, the depletion of forest areas and wetlands, the extinction of animal and plant species, and the deterioration in air and water quality (especially in Eastern Europe and the former USSR) pose serious long-term problems that governments and peoples are only beginning to address 
Land use arable land: 10% 
permanent crops: 1% 
permanent pastures: 26% 
forests and woodland: 32% 
other: 31% (1993 est.) 
Irrigated land 2,481,250 sq km (1993 est.) 
Natural hazards  large areas subject to severe weather (tropical cyclones), natural disasters (earthquakes, landslides, tsunamis, volcanic eruptions) 
Environment 
current issues
 large areas subject to overpopulation, industrial disasters, pollution (air, water, acid rain, toxic substances), loss of vegetation (overgrazing, deforestation, desertification), loss of wildlife, soil degradation, soil depletion, erosion 
Environment 
international agreements
selected international environmental agreements are included under the Environment - international agreements entry for each country and in the Selected International Environmental Agreements appendix