Environment

Sanitation: systems, health impacts, history and common technologies Sanitation Sanitation is the set of practices and systems that safely manage human waste, wastewater and refuse to protect health, water resources and the environment worldwide.

Scrap: recyclable materials, processing, and role in industry Scrap An overview of scrap materials, how they are collected and processed, their uses in manufacturing and the economy, environmental benefits, regulatory issues and distinctions from w…

Scrubbers: industrial systems for removing airborne pollutants Scrubber Scrubbers are pollution-control devices that remove sulfur, particulates and other contaminants from industrial exhaust. This article explains types, operation, byproducts, history…

Season A season is a recurring division of the year marked by characteristic weather, daylight and ecological changes, produced mainly by Earth's axial tilt; different regions use differe…

Sewage (domestic wastewater): sources, risks and treatment Sewage Sewage is the liquid waste produced by households and some industries. This article outlines what sewage contains, where it comes from, how it is conveyed and treated, and its heal…

Sherbino Wind Farm — Pecos County, Texas Sherbino Wind Farm Large onshore wind farm in Pecos County, Texas. Phase I (150 MW) uses 50 Vestas V90 turbines; project planned to reach 750 MW. Operated by BP and developed in multiple phases.

Shifting cultivation (swidden) — traditional rotating agriculture Shifting cultivation Shifting cultivation is a form of small-scale rotating agriculture in which plots are farmed for a few seasons and then left fallow to regenerate vegetation and soil fertility.

Silent Spring — Rachel Carson's 1962 book on pesticides and the environment Silent Spring Silent Spring (1962) by Rachel Carson documented ecological harms from widespread pesticide use, highlighted effects on wildlife, and helped catalyze public debate and policy chang…

Small Island Developing States (SIDS) Small Island Developing States Small Island Developing States are island and low-lying coastal countries facing unique development challenges — small markets, limited resources, distance, and high vulnerability…

Smokey Bear: U.S. wildfire-prevention mascot and cultural symbol Smokey Bear Smokey Bear is the long-running U.S. wildfire-prevention mascot created in 1944. This article covers his origin, slogans, appearance, legal protection, stewardship and cultural inf…

Stockholm Convention on Persistent Organic Pollutants A global treaty (adopted 2001, effective 2004) to eliminate or restrict persistent organic pollutants (POPs), set rules for their management, and promote safer alternatives while a…

Storm history of Hurricane Ivan (2004) Storm history of Hurricane Ivan Comprehensive meteorological history of Hurricane Ivan (2004), covering its origins, intensification, track through the Caribbean and Gulf Coast, regeneration, and notable records…

Sustainability: concepts, principles, history and practical applications Sustainability Sustainability is the practice of meeting present needs without compromising future generations. This article explains its pillars, guiding principles, history, uses, and common ch…

Sustainable biofuels: types, production, benefits and challenges Sustainable biofuels An overview of sustainable biofuels: feedstocks, production pathways, environmental and social considerations, uses, policy levers, and distinctions between conventional and advanc…

Sustainable development: principles, history, and practical approaches Sustainable development Balanced development that meets present human needs while conserving natural systems and opportunities for future generations; covers environmental, economic and social dimensions.

Sustainable Development Goals (SDGs): global framework for 2030 Sustainable Development Goals The Sustainable Development Goals are 17 global objectives adopted by United Nations member states in 2015 under the 2030 Agenda, with 169 targets to end poverty, protect the plane…

Sustainable energy: principles, technologies, and global importance Sustainable energy Overview of sustainable energy: efficiency and renewable supply, supporting technologies, policy tools, environmental and social considerations, implementation challenges, and futu…

Swamp: forested wetland — types, ecology, and notable examples Swamp Swamps are forested wetlands saturated with fresh, brackish, or salt water. They host rich biodiversity, store carbon, reduce floods, and filter water. Major examples include the P…

Thames River (Connecticut) A short tidal river in eastern Connecticut that flows from Norwich to Long Island Sound, forming New London Harbor and noted for its maritime history, naval base, and state parks.

The Dirty Energy Dilemma: arguments, solutions and the debate over clean power The Dirty Energy Dilemma Overview of Benjamin K. Sovacool's 2008 book The Dirty Energy Dilemma, its main arguments for efficiency and renewables, reception, and the wider debate about nuclear energy and en…

Toxic waste: types, sources, risks and management Toxic waste Toxic waste comprises materials harmful to humans, animals, or ecosystems. This article explains types, sources, health and environmental impacts, historical development, and commo…

Tragedy of the commons A concept describing how individual use of shared resources can degrade them, with roots in 19th-century economics and a pivotal 1968 essay by Garrett Hardin.

Tropical Storm Edouard (2008) A short-lived Gulf of Mexico tropical storm in early August 2008 that formed from a northeastern Gulf disturbance, made landfall on the upper Texas coast, and produced heavy inland…

Tropical Storm Melissa (2007) Short-lived Atlantic tropical storm in September 2007 that formed southwest of the Cape Verde islands, remained weak due to wind shear, dissipated over open water, and tied a Septe…

Turbidity: causes, measurement, and significance for water quality Turbidity Turbidity is the cloudiness of water caused by suspended particles. This article explains its causes, measurement methods, units, impacts on ecosystems and human use, and approache…

Underwater Observatory Marine Park, Eilat Underwater Observatory Marine Park Eilat A public aquarium, conservation centre and underwater observatory at the southern end of Eilat’s Coral Beach Nature Reserve, showcasing Red Sea marine life and educational programs…

United Nations Environment Programme (UNEP) United Nations Environment Programme UNEP coordinates UN environmental work, supports policy and capacity building for sustainable development, and fosters science–policy links from its Nairobi headquarters since 1972…

United Nations Framework Convention on Climate Change (UNFCCC) United Nations Framework Convention on Climate Change International environmental treaty establishing a framework for global cooperation to limit human-driven climate change and coordinate national responses.

United States Environmental Protection Agency (EPA) United States Environmental Protection Agency Independent federal agency established in 1970 to protect human health and the environment through regulation, enforcement, research, grants and partnerships across the United Stat…

U.S. House Oversight Subcommittee on Environment United States House Oversight Subcommittee on Environment A congressional subcommittee that conducts oversight of federal environmental programs, agencies and policy implementation, using hearings, investigations and reporting to ensure a…

United States Senate Committee on Environment and Public Works Senate committee responsible for federal environmental policy, public works and infrastructure oversight, with roles in legislation, agency oversight, and review of related nominat…

U.S. Senate Environment and Public Works Subcommittee on Green Jobs and the New Economy United States Senate Environment and Public Works Subcommittee on Green Jobs and the New Economy Overview of the Senate EPW Subcommittee on Green Jobs and the New Economy: purpose, jurisdiction, activities, historical context, policy importance, and debates about measuring and…

U.S. Senate Environment and Public Works Subcommittee on Transportation and Infrastructure United States Senate Environment Subcommittee on Transportation and Infrastructure Senate subcommittee that shapes federal policy and oversight for public buildings, highways, surface transportation and related infrastructure programs in the United States.

Urban Heat Island (UHI): Causes, Effects and Mitigation Urban heat island An urban heat island is a city area that becomes significantly warmer than surrounding rural zones. This article explains its causes, impacts, measurement, and common mitigation st…

Voluntary Human Extinction Movement (VHEMT) Voluntary Human Extinction Movement An overview of the Voluntary Human Extinction Movement: its aims, history, rationale, criticisms and cultural influence, and how it fits into broader environmental debates.

Vulnerability: social, environmental, and technical meanings Vulnerability Vulnerability describes the degree to which people, systems, or assets are likely to experience harm from hazards, stresses, or shocks, encompassing exposure, sensitivity and adapt…

Vulnerable species (conservation status) Vulnerable species Summary of the IUCN 'Vulnerable' category: assessment criteria, typical threats, conservation responses, differences from other Red List categories, and pointers to further resourc…

Waste: types, management, impacts and distinctions Waste Materials or substances discarded after use. Overview of types (solid, liquid, gas, heat), historical development, management strategies, environmental and health impacts, and key…

Water footprint A measure of the freshwater consumed and polluted in producing goods, services or supporting populations; broken into blue, green and grey components and used in policy, business a…

Water pollution: causes, impacts, and responses Water pollution Comprehensive overview of water pollution: types, sources, common pollutants, ecological and human impacts, monitoring, prevention, treatment, and policy responses.

Water purification: methods, history and applications Water purification Comprehensive overview of water purification: goals, common techniques (filtration, disinfection, membranes), historical development, uses, contaminants, and modern challenges incl…

Water scarcity: causes, impacts, and responses Water scarcity An overview of water scarcity: what it is, key causes both natural and human, consequences for societies and ecosystems, historical context and practical responses to reduce shorta…

Wildfire: causes, behaviour, ecological role and management Wildfire Comprehensive overview of wildfires: types, causes, behaviour, ecological effects, risks to people and property, and common approaches to prevention, detection and suppression.

Wildlife management: principles, history, methods, and contemporary practice Wildlife management Overview of wildlife management: aims, methods, disciplines, governance, and contemporary challenges in balancing species, habitats and human needs.

Wind power in the United States An overview of wind power in the United States: development, scale, technology, policy drivers, economic impacts, challenges, and future prospects.

World Environment Day Annual United Nations day on June 5 that promotes environmental action worldwide, guided by a yearly theme and coordinated by the United Nations Environment Programme.

Worldwatch Institute: independent research on the global environment and economy Worldwatch Institute Independent Washington, D.C.-based research organization that analyzes global environmental trends, sustainable development, and policy responses; publisher of State of the World a…

Xfce — lightweight desktop environment for Unix-like systems Xfce Xfce is a free, open-source desktop environment for Unix-like systems that emphasizes speed, low resource use, modularity and ease of use. Often used on older hardware and lightwei…