2,436 articles
Humboldt River
Humboldt River: Nevada river rising at Humboldt Wells, flowing over 300 miles to the Humboldt Sink; Nevada's only major internal river basin, emigrant trail artery, and irrigated water source with Rye Patch Dam.
Humedales del Delta del Río Colorado
Humedales del Delta del Río Colorado: two Ramsar wetland sites (814, 1996, 250,000 ha; 1822, 2008, 127,614 ha) in Baja California and Sonora, Mexico, desert wetlands on the Pacific Flyway fed by canal seepage and irrigation return flows.
Hunter Estuary
The Hunter Estuary is the tidal lower reach of the Hunter River in New South Wales, Australia, where it meets the Tasman Sea at Newcastle.
Huon Bay
Huon Bay is a shallow Antarctic bay about 8 miles wide between Cape Ducorps and Cape Legoupil on the northwest coast of Louis Philippe Peninsula, at 63°23'S 58°00'W, named by d'Urville's 1837-40 expedition for Félix Huon de Kermadec.
Huron River
Huron River, a river of southeastern Michigan rising near Pontiac and flowing about 80 miles to Lake Erie; drains roughly 1,000 square miles across seven counties and supplies Ann Arbor's drinking water.
Husky Lakes
Husky Lakes (Imaryuk, formerly Eskimo Lakes) is a five-basin Arctic estuarine system on the Tuktoyaktuk Peninsula, NWT, Canada, draining to Liverpool Bay; ecologically significant, Inuvialuit-harvested, protected under the Inuvialuit Final Agreement.
Hutt Lagoon
Hutt Lagoon (Pink Lake) is a ~70 km² hypersaline coastal brine lagoon near Port Gregory, Western Australia, pink from Dunaliella salina carotenoids, hosting the world's largest microalgae beta-carotene farm and a former 1924 salt industry.
Hydrogeomorphic approach to wetland classification and assessment
The hydrogeomorphic (HGM) approach is a US method for classifying wetlands and scoring their ecological functions, developed by the Army Corps of Engineers in the early 1990s.
Hydrosere
Hydrosere: the seral sequence of ecological succession beginning in open water (pond, lake, swamp), also called hydrarch succession, running from phytoplankton through marsh stages toward a terrestrial climax; counterpart of the xerosere.
Iapetus Ocean
Iapetus Ocean, the proto-Atlantic paleo-ocean proposed by J. Tuzo Wilson in 1966, opened between Laurentia, Baltica, and Avalonia in the late Neoproterozoic and closed in the Silurian, forming the Caledonian–Appalachian orogen and the Iapetus suture.
Ice Cover
Ice cover: ice on oceans, lakes, rivers, and land (sea ice, freshwater ice, ice sheets). Sea ice covers ~9% of oceans; Arctic ice has thinned and shrunk sharply since 1979.
Ice jam
An ice jam is an accumulation of broken river ice that lodges at an obstruction or constriction and blocks a stream's flow, impounding water that floods upstream.
Iceland - Jan Mayen
Iceland - Jan Mayen, FEOW freshwater ecoregion 401 (Polar freshwaters), pairs Iceland with the Norwegian volcanic island Jan Mayen; known for endemic Thingvallavatn charr, glacial rivers, and scarce Jan Mayen fresh water.
Iguassu
Iguassu (FEOW ecoregion 346) is the freshwater ecoregion of the Iguaçu River basin above Iguaçu Falls in Brazil and Argentina, isolated 22 million years, with about 39 endemic fish species, dam fragmentation, pollution, and a last free-flowing reach in Iguaçu National Park.
Iguazu Falls
Iguazu Falls (Cataratas del Iguazú / Cataratas do Iguaçu): about 275 cascades up to 80 m high across a 2.7 km front on the Argentina–Brazil border; UNESCO World Heritage since 1984/1986 and a New 7 Wonders of Nature site (2012).
IJ (Amsterdam)
The IJ is Amsterdam's central waterway, once a Zuiderzee tidal bay, now running from the IJmeer to the North Sea Canal. Key facts: 1876 canal, GVB ferries, IJburg islands, IJmuiden salt management.
IJsselmeer (landform)
The IJsselmeer is a large artificial freshwater lake in the central Netherlands, created in 1932 when the Afsluitdijk closed the Zuiderzee, making it the country's largest freshwater lake.
Ili
Ili (Ile; 伊犁河): transboundary Central Asian river rising in Xinjiang's Tianshan, flowing through Kazakhstan into Lake Balkhash, supplying 70-80% of its inflow; no China-Kazakhstan allocation agreement.
Iliamna (lake)
Iliamna Lake (Dena'ina: Nila Vena; Central Yup'ik: Nanvarpak) is a large freshwater lake in southwestern Alaska and the state's largest, known for world-important sockeye salmon habitat and rare freshwater harbor seals.
Impatiens capensis
Impatiens capensis (orange jewelweed, spotted touch-me-not; synonym I. biflora) is a North American annual wetland herb with orange spurred flowers, explosive 4.2 ms seed pod dehiscence, cleistogamous flowers, and introduced populations in Europe and western North America.
Inaccessible Island
Inaccessible Island: uninhabited 14 km² volcanic island in the Tristan da Cunha group, South Atlantic, part of the UK Overseas Territory of St Helena, Ascension and Tristan da Cunha; World Heritage Site since 2004, home of the Inaccessible Rail and Spectacled Petrel, with no introduced mammals.
Indian Ocean Basin mode
The Indian Ocean Basin mode (IOB) is the dominant pattern of year-to-year sea surface temperature variability in the tropical Indian Ocean, a basin-wide warming or cooling.
Indian Ocean Dipole
Indian Ocean Dipole (IOD), measured by the Dipole Mode Index, is a sea surface temperature seesaw between the western and eastern tropical Indian Ocean with positive, negative, and neutral phases, discovered by Saji et al. in 1999, affecting East African, Indonesian, and Australian rainfall.
Indian Ocean garbage patch
The Indian Ocean garbage patch is a poorly defined accumulation of floating plastic in the southern Indian Ocean subtropical gyre, southeast of Madagascar; unlike the Pacific and Atlantic patches it is weak, dispersive, and under-sampled, and no northern patch exists because land blocks the gyre.
Indian Ocean Geoid Low
The Indian Ocean Geoid Low (IOGL) is Earth's lowest geoid anomaly, a −106 m depression south of India caused by low-density mantle plume material generated when Tethyan slabs perturbed the African LLSVP.
Indian Ocean Slope of Sumatra & Java
Indian Ocean Slope of Sumatra & Java, FEOW freshwater ecoregion 737, tropical and subtropical coastal rivers of southwestern Sumatra and Java plus offshore islands, with about 20 endemic fishes and Lake Maninjau.
Indian Ocean trade
Indian Ocean trade: maritime commerce linking East Africa, Arabia, Iran, India, Southeast Asia, and China from the Bronze Age onward, driven by monsoon winds, centered on Indian textiles and spices, and predating European entry by millennia.
Indian oil sardine
Indian oil sardine (Sardinella longiceps), a small tropical pelagic fish of the northern Indian Ocean and India's key sardine fishery, contributing 17–20% of national marine landings, centered on Kerala's Malabar upwelling zone.
Indonesian Throughflow
Indonesian Throughflow (ITF, Arus Lintas Indonesia): the only tropical interocean current, carrying warm, fresh Pacific water through Indonesian straits into the Indian Ocean at about 15 Sv, mainly via Makassar Strait, affecting ENSO and global climate.
Indus Delta
Indus Delta, river delta of the Indus in Sindh, Pakistan; fifth largest delta worldwide, Ramsar site 1284 (472,800 ha), arid-climate mangroves, severe seawater intrusion and land loss from upstream irrigation diversion.