Yenisei (Енисе́й) is the greatest river system flowing to the Arctic Ocean, and at 5,539 km (3,445 mi) is the fifth longest river in the world. Rising in Mongolia, it follows a northerly course to the Yenisei Gulf in the Kara Sea, draining a large part of central Siberia, the longest stream following the Yenisei-Angara-Selenga-Ider.
The upper reaches, subject to rapids and flooding, pass through sparsely populated areas. The middle section is controlled by a series of massive hydroelectric dams fuelling significant Russian primary industry. Partly built by gulag labor in Soviet times, industrial contamination remains a serious problem in an area hard to police. Moving on through sparsely-populated taiga, the Yenisei swells with numerous tributaries and finally reaches the Kara Sea in desolate tundra where it is icebound for more than half the year.
The Yenisei rises in two major headstreams: the Bolshoi (greater) Yenisey also known as the Bii-Khem (Бий-Хем) rises in the Tuva region on the S flank of the Eastern Sayan Mountains and north of the Tannu-Ola Mountains at ; the Malyy (lesser) Yenisey· also known as the Kaa-Khem (Каа-Хем) rises in the Darkhad (rift) valley in Mongolia. Recent research has shown that the narrow exit to the Darkhad Valley has regularly been blocked by ice producing a lake as large as neighbouring Lake Khövsgöl. When the glaciers retreated (the last time 9300 years BP) as much as 500 km³ of water would have escaped, possibly catastrophically.
Angarsk, the center of the expanding Eastern Siberian oil industry and site of a huge Yukos-owned refinery, lies 50 km downstream of Irkutsk. A major pipeline takes oil west, and a new one is being built to carry oil east for supply to Japan from the Sea of Japan port of Nakhodka. The exact potential of Eastern Siberia is unknown, but two new major fields are the Kovyktinskoye field near Zhigalovo 200 km north of Irkutsk and the extremely remote Verkhnechonskoye field 500 km north of Irkutsk on the Central Siberian Plateau.
The river is icebound for more than half the year, and if unchecked ice could dam the river causing major flooding. Explosives are used to keep the water flowing. The final town is Dudinka which is connected to Krasnoyarsk by regular passenger boat. The river widens to a 50 km estuary, the Yenisei Gulf, for its final 250 km and the shipping lanes are kept open by icebreaker.
During the ice age, the route to the Arctic was blocked by ice. Though the exact details are unclear, the Yenisei is believed to have flowed into a huge lake filling much of western Siberia, eventually flowing into the Black Sea. (See West Siberian Glacial Lake of the early Weichselian Glaciation)
The canal is now fully abandoned. It is occasionally reached by tourists using canoes, cars, or bicycles, or on foot. The first team to navigate the Yenisey's entire length, including its violent upper tributary in Mongolia, was an Australian-Canadian effort completed in September 2001. Ben Kozel, Tim Cope, Colin Angus and Remy Quinter were on this team. Both Kozel and Angus wrote books detailing this expedition, and a documentary was produced for National Geographic Television.
Tim Cope's Yenisei River journey was recorded at, http://www.timcopejourneys.com/index.pl?page=44
The relationship of mineral and geochemical composition to artificial radionuclide partitioning in Yenisei river sediments downstream from mining-and-chemical combine Rosatom.(Report)
Jul 01, 2011; 1. INTRODUCTION Earth's ecosystems, including aquatic ones, have accumulated large amounts of artificial radionuclides....