Encyclopedia britannica

20th century abundance agriculture altitude ancient animals Arctic Arctic Ocean Argentina Aristotelian Aristotle Aristotle's arthropods aschelminths Asian Athens Atlantic atmosphere atoms basin Buenos Aires carbon Caspian Central Asia centre chemical China Chinese climate coast criticism cultural delta deposits desert east eastern economic electrons energy ethnic Evenk exploration feet flow forest gases glaciers Greenland groups Gulf Himalayas Hindu Hindu Kush hydrogen important India Indus irrigation islands isotopes Karakoram kilometres land language major marginal mass Mediterranean metres miles million years ago modern molecules mountains Myanmar neutrons northern nuclear nucleons nucleus occur Ocean orbitals oxygen painting Pamirs particles patterns Peninsula plains Plateau political population production protons radioactive range reaction region River Russian Siberia slopes soil Southeast Southeast Asia southern species structure summer surface temperature theory Tibet Tien Shan tion trade traditional tundra valley western winter Yangtze zone