2,436 articles
Pitman Fracture Zone
Pitman Fracture Zone, formerly Fracture Zone XII, a right-stepping fracture zone on the Pacific-Antarctic Ridge at about 65 degrees S; initiated at chron C27, named for Walter C. Pitman III, records 65 Myr of plate motion and late Neogene transtension.
Pittwater
Pittwater is a tide-dominated drowned river valley estuary north of Sydney, NSW, connected to the Hawkesbury River; 18.4 km², average depth 9.9 m, named by Governor Phillip in 1788, formerly governed by Pittwater Council (1992–2016).
Plaine de Massenya
Plaine de Massenya is a 2,526,000-hectare Ramsar wetland (site no. 1839) in southwestern Chad's Baguirmi region, a Chari River floodplain depression designated in 2008 with 386 bird species.
Plaines d'inondation des Bahr Aouk et Salamat
The Plaines d'inondation des Bahr Aouk et Salamat is a vast Ramsar wetland in southeastern Chad, designated in 2006 and then the world's third-largest Ramsar site.
Plata Passage
Plata Passage, also Admiral Merino Channel (Canal Almirante Merino), is a passage in Wilhelmina Bay, Antarctic Peninsula, separating Brooklyn Island from the Danco Coast; charted by the Belgian Antarctic Expedition in 1898 and named for the Rio de la Plata.
Platte River
The Platte River, formed by the North and South Platte in Nebraska, is a braided Great Plains river flowing to the Missouri. Known for sandhill crane staging, whooping crane critical habitat, and Colorado-Nebraska water disputes.
Plétipi
Lake Plétipi (Lac Pletipi) is one of the largest lakes of Quebec, Canada, in the remote Côte-Nord interior, with a 210-mile shoreline of spits and deeply indented bays.
Plymouth Sound
Plymouth Sound is a large natural harbour in southwest England where the Tamar and Plym meet the English Channel. It anchors the Plymouth Sound and Estuaries MPA and the UK's first National Marine Park, with over 200 shipwrecks and Devonport Dockyard on its shores.
Po (river)
Po (landform): Italy's longest river, 652-661 km, rising at Monte Viso and flowing to the Adriatic near Venice; nine-branch delta, about 1,500 m3/s mean discharge, heavily managed and drought-prone.
Poços de Caldas
Poços de Caldas, a spa city in southern Minas Gerais, Brazil, founded 6 November 1872 around sulfurous thermal springs on an extinct volcanic caldera; known for its hydrothermal heritage complex, Palace Casino era, and high development indices.
Pollardstown Fen
Pollardstown Fen is a spring-fed calcareous fen near Newbridge in County Kildare, Ireland, the largest in the country and a National Nature Reserve, Ramsar site, and Special Area of Conservation.
Pollution of the Ganges
Pollution of the Ganges: contamination of India's Ganga river by untreated sewage (over 80% of load), industrial effluent, and runoff, addressed since the 1985 Ganga Action Plan and the 2014 Namami Gange Programme, with persistent capacity and utilization gaps.
Polynesian navigation
Polynesian navigation, or wayfinding, is non-instrument Pacific navigation by stars, swells, winds, clouds, and birds. Key facts: Sharp's accidental-voyage theory, Hōkūleʻa's 1976 Hawaii–Tahiti voyage under Mau Piailug, and the modern voyaging revival.
Pond
Pond: a small, shallow standing waterbody (<5 ha, <5 m, <30% emergent vegetation per a 2022 definition), distinct from lakes and wetlands; globally abundant, biodiverse, and often human-made for farming, stormwater, or swimming.
Pong Dam Lake
Pong Dam Lake (Maharana Pratap Sagar) is a 1975 Beas River reservoir in Kangra, Himachal Pradesh; a Ramsar wetland and sanctuary hosting 45% of the world's wintering bar-headed geese.
Pool
Pool: a deep, slow-water topographic low in a riverbed alternating with riffles every 3–5 channel widths; formed by flow obstructions or free-formed scour; also oil-and-gas reservoirs and marsh pools.
Porcupine Abyssal Plain
Porcupine Abyssal Plain: flat abyssal seafloor in the Northeast Atlantic southwest of Ireland, about 4,850 m deep, home since 1985 to the PAP-SO ocean observatory, one of two abyssal long-term time-series sites worldwide.
Porpoise Bay
Porpoise Bay names several bays: one at the head of Sechelt Inlet, British Columbia (named 1860 by Captain Richards), a 170-km-wide embayment in Wilkes Land, Antarctica (named for the brig Porpoise), and a Catlins beach bay in New Zealand.
Port Jackson
Port Jackson, commonly called Sydney Harbour, is the drowned valley estuary at Sydney, New South Wales, named by Cook in 1770 and the site of the First Fleet's 1788 settlement at Sydney Cove.
Port of Palos
Port of Palos (Puerto Histórico de Palos), the Tinto river port of Palos de la Frontera, Huelva, Spain, from which Columbus's Santa María, Pinta, and Niña sailed on 3 August 1492; buried after 1503, rediscovered in 1992.
Port Phillip
Port Phillip (Port Phillip Bay) is a 1,930 km² shallow bay in Victoria, Australia, entrance the Rip, home of Melbourne and its port, Ramsar wetlands, and Victoria's biggest recreational fishery.
Possum Kingdom Lake
Possum Kingdom Lake: Brazos River reservoir in Palo Pinto County, Texas, formed by Morris Sheppard Dam (completed 1941), the first water supply reservoir in the Brazos basin, run by the Brazos River Authority, 538,139 acre-feet, known for clear water, striped bass, and golden alga fish kills.
Potomac River
The Potomac River is a 400-mile mid-Atlantic river flowing to Chesapeake Bay, supplying 80 percent of Washington, DC's drinking water, site of the 2026 Potomac Interceptor sewage spill.
Powell Basin
Powell Basin: small ocean basin off the northernmost Antarctic Peninsula (50°W, 62°S), northwestern Weddell Sea; formed by rifting of the South Orkney Microcontinent, with slow seafloor spreading roughly 29.7-21.8 Ma; distinct from Lake Powell, Utah.
Poyang
Poyang, also called Pengli Lake (鄱阳湖), is China's largest freshwater lake, in Jiangxi Province about 50 km north of Nanchang, draining into the Yangtze River.
Praia do Tonel
Praia do Tonel is a west-facing beach and surf break at Sagres, Algarve, below the Sagres Fortress, known for consistent Atlantic swell, strong rip currents, Blue Flag status, and winter surf up to 2 m.
Prehistoric pile dwellings around the Alps
Prehistoric Pile Dwellings around the Alps (Pfahlbauten): UNESCO serial property of 111 stilt-house settlement sites, 5000-500 BC, in six Alpine countries, 56 in Switzerland, inscribed 2011 under criteria (iv) and (v).
Preservation in situ of waterlogged archaeological sites
Preservation in situ of waterlogged archaeological sites means leaving organic remains like wood buried in oxygen-poor waterlogged ground, the first option under the 1992 Valletta Convention.
Primero de Mayo Bay
Primero de Mayo Bay (bahía Primero de Mayo; Fumarole Bay, Bahía Septiembre) is a bay on the SW side of Port Foster, Deception Island, South Shetland Islands, named by Argentina's 1942-43 expedition after the ship 1 de Mayo, with active beach fumaroles.
Prince Albert Sound
Prince Albert Sound (Kangiryuaq) is a 120-mile-long Arctic sound on Victoria Island, Northwest Territories, Canada, an inlet of Amundsen Gulf separating Wollaston Peninsula; known for ringed seal habitat, Ulukhaktok at its entrance, and 1851 Rae exploration.