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• Glossary

Glossary

Definitions for the terms we use on our web site.

• Alternative fuels: substitutes for traditional oil-derived liquid motor vehicle fuels like gasoline and diesel. Includes biodiesel, hydrogen, electricity, compressed natural gas, methanol, ethanol, and mixtures of alcohol-based fuels with gasoline.
• Bay-Friendly landscaping and gardening: a holistic approach to gardening and landscaping that works in harmony with the natural conditions of the San Francisco Bay Watershed. Bay-Friendly practices foster soil health and conserve water and other valuable resources while reducing waste, preventing pollution, and providing habitats for birds, beneficial insects, and other creatures. Practices can include using mulch, permeable pavement, smart irrigation controllers, and planting with native vegetation.
• Bioaccumulative: refers to the process by which the concentrations of some toxic chemicals such as mercury gradually increase in living tissue, such as in plants, fish, or people as they breathe contaminated air, drink contaminated water, or eat contaminated food.
• Biodiesel: a form of diesel fuel manufactured from vegetable oils (used or new) or animal fats. Biodiesel can be used in its pure form (B100) or blended with petroleum diesel in various proportions (e.g., B20 is 20 percent biodiesel, 80 percent petroleum diesel).
• CO₂E: equivalent carbon dioxide units. Emissions from different types of greenhouse gases (carbon dioxide [CO₂], methane [CH₄], and nitrogen dioxide [N₂O]) are reported in terms of equivalent carbon dioxide units. Converting all emissions to equivalent carbon dioxide units allows for the consideration of different greenhouse gases in comparable terms.
• Carbon footprint: the total set of greenhouse gas emissions caused directly and indirectly by an individual, organization, event, or product.
• Climate change: refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). There is international concern that increasing concentrations of greenhouse gases (GHGs) in the atmosphere are changing the climate in ways detrimental to our social and economic well-being.
• Coir rolls: rolled up coconut fibers bound with woven twine used to stabilize eroding stream banks and hill slopes.
• Composting: the controlled process of breaking down plant trimmings and kitchen scraps into a dark-colored, sweet-smelling soil amendment that adds nutrients to the soil.
• Culvert: concrete box or pipe that is designed to carry typically water underground.
• Daylighting: excavating and restoring creek corridors that have been placed in underground culverts or pipes to more natural (above ground) conditions.
• Ecosystem: an ecological community of interdependent plant and animal species and their physical environment.
• Emission: in the context of climate change, the release of a substance (usually a gas) into the atmosphere.
• Environmentally Preferable Purchasing: the procurement or acquisition of goods and services that have a lesser or reduced effect on human health and environment when compared with competing goods or services that serve the same purpose. This comparison takes into consideration, to the extent feasible, raw materials acquisition, production, manufacturing, packaging, distribution, reuse, operation, maintenance, disposal, energy efficiency, product performance, durability, safety, the needs of the purchaser, and cost.
• Fish screen: a device installed to prevent fish from swimming or being drawn into an aqueduct, cooling water intake, dam, or other diversion on a river, lake, creek, or other waterway.
• Fish run: the place where fish, such as native steelhead trout and salmon, return from the ocean each spring to spawn in the rivers or streams where they were born. Can also refer to the group of fish that is migrating up the stream.
• Fuel cell: a device that continuously changes the chemical energy of a fuel (such as hydrogen) and an oxidant directly into electrical energy.
• General plan: a long range policy document to guide land use decisions about physical, economic, and environmental growth. California state law requires counties and cities to have a General Plan which contains seven elements: Land Use; Transportation; Housing; Open Space; Conservation; Safety and Noise. County general plans cover unincorporated areas.
• Global warming: an increase in the near surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases.
• Green building: a building constructed using a design philosophy which focuses on increasing the efficiency of resource use (e.g., energy, water, and materials) while reducing building impacts on human health and the environment during the building's life cycle through better siting, construction, operation, maintenance, and removal.
• Greenhouse effect: carbon dioxide and other atmospheric gases warm the surface of the planet naturally by trapping heat close to the surface of the Earth. In a natural state, the greenhouse effect warms the planet, making it habitable by humans. However, human activities have dramatically increased the amount of carbon dioxide and other greenhouse gases in the atmosphere. Higher levels of greenhouse gases trap more heat, causing temperatures to rise, just like you would experience in an actual greenhouse.
• Greenhouse gas: a gas, including water vapor, carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), which contributes to climate change.
• Integrated pest management: an approach to pest control that aims to avoid pesticide use and utilizes regular monitoring to determine if and when intervention is needed and uses physical, mechanical, cultural, biological and educational tactics to keep pest numbers low enough to prevent unacceptable damage or annoyance. Least-toxic chemical controls are used as a last resort.
• Invasive species: invasive species are plants or animals that originated somewhere else, thrive here, and can take over local species. Some examples of invasive plants in the Bay Area are scotch broom, periwinkle, and ice plant.
• Kilowatt: one thousand watts. A watt is a unit of power that measures the rate of energy conversion.
• Kilowatt-hour: the amount of energy equivalent to a steady power of 1 kilowatt running for 1 hour. Energy production or consumption for a period is often expressed as kilowatt- or megawatt-hours produced or consumed during the period. Your energy bill is probably stated in cents per kilowatt-hour. A U.S. household might consume 10,000 kilowatt-hours per year.
• Land use planning: the process by which decisions are made on future land uses and disposition of resources, facilities, and services with a view to securing the physical, economic and social efficiency, health, and well-being of urban and rural communities.
• Life cycle: a product or service has environmental impacts throughout its life cycle, both long before and long after it is purchased and used. A product's life cycle includes activities associated with raw material acquisition, product manufacturing, packaging and transportation, product use, and ultimate disposal.
• Megawatt: one million watts. A watt is a unit of power that measures the rate of energy conversion.
• Persistent bioaccumulative toxins (PBTs): chemicals that are toxic, persist in the environment and bioaccumulate in food chains and, thus, pose risks to human health and ecosystems. The biggest concerns about PBTs are that they transfer rather easily among air, water, and land, and span boundaries of geography and generations.
• Plug-in hybrid: a hybrid vehicle with batteries that can be recharged by connecting a plug to an electric power source. It shares the characteristics of both traditional hybrid electric vehicles, having an electric motor and an internal combustion engine, and of battery electric vehicles, also having a plug to connect to the electric grid.
• Recycled-content products: products made from materials that would otherwise have been discarded. These products are made totally or partially from material contained in the products you recycle, such as aluminum cans or paper. Recycled-content products also can be items that are rebuilt or re-manufactured from used products, such as toner cartridges.
• Recycle: minimizing waste generation by recovering and reprocessing usable products that might otherwise become waste, such as recycling of aluminum cans, paper, and bottles.
• Retrofit: refers to the addition of new technology or features to older systems, such as adding new energy-efficiency lamps to existing lighting fixtures.
• Reuse: using a product or component of municipal solid waste in its original form more than once, such as refilling a glass bottle or using a coffee can to store small items.
• Rock weir: a structure used in small- to medium-sized streams to slow and control the direction of stream flow and stabilize the gradient of the streambed. They are made by arranging large rocks in a line across the streambed. The rocks on the edges are highest and buried into the stream banks while the rocks in the center are lowest (usually no more than one foot above the streambed) to funnel the flow through the middle of the stream.
• Runoff: that part of precipitation, snow melt, or irrigation water that runs off the land into streams or other surface water. It can carry pollutants from the air and land into receiving waters. Impervious paved areas generate additional runoff which can cause erosion and flooding.
• Streetscape: the visual elements of a street, including the road, adjoining buildings, street furniture, trees, and open spaces, etc., that combine to form the street's character.
• Source Reduction: any change in the design, manufacture, purchase, or use of materials or products, including packaging, to reduce the amount that will become municipal solid waste.
• Sustainability: in a broad sense, the capacity to endure. In ecology, the word describes how biological systems remain diverse and productive over time. For human society, it is the potential for long-term maintenance of well-being, which in turn depends on the well-being of the natural world and the responsible use of natural resources. Sustainability has three facets: environmental, economic, and social.
• Transitional housing: time-limited supportive housing for individuals who are otherwise homeless that is attached to supportive services.
• Unincorporated areas: a region of land that is not part of a municipality (city). To "incorporate" in this context means to form a municipal corporation - a city or town with its own government. Thus, an unincorporated community is usually not subject to or taxed by a municipal government. Such regions are generally administered as a part of larger administrative division, such as a county.
• Waste diversion: a waste reduction strategy focused on the recycling or composting of materials, thereby recovering what would otherwise have been waste for use in new products.
• Waste reduction: using source reduction, recycling, or composting to prevent or reduce waste generation.
• Waste stream: the total flow of solid waste from homes, businesses, institutions, and manufacturing plants that is recycled, burned, or disposed of in landfills.
• Watt: the measure of the rate of electrical use at any moment. For example, a 60 watt bulb uses 60 watts.
• Volatile organic compounds (VOCs): VOCs are made of carbon, oxygen, hydrogen, chlorine, and other atoms that can form gases easily. They are found in nature as well as in some glue, paint, solvents, and other products. They help form ozone near the ground, which can harm human health.

Sources of definitions include the U.S. Environmental Protection Agency, StopWaste.Org, the California Environmental Protection Agency, the Bio-integral Resource Center, the State of Oregon Department of Environmental Quality, the Municipal Research and Services Center of Washington, Canadian Department of Industry, Merriam-webster.com, Wikipedia, and wiktionary.

Related Links:

• U.S. Environmental Protection Agency glossary