Celebrating Earth Day

A mild acidic solution that falls in rain or as dry particles caused when fossil fuel burning produces sulfur dioxide and nitrogen oxides. Acid rain has been linked to damaging effects on waterways and forests.

A strategy for designing high-performance, ultra-energy-efficient buildings. Active solar incorporates all the elements of a passive solar design with additional mechanical equipment, such as pumps or fans, to take advantage of the heat from the sun.

Wind, hydro (water), biomass (fuel from natural material such as crops and agricultural waste), and solar power.

Made from materials that will decay and break down into naturally occurring elements in a fairly short amount of time.

Fuel made from natural material such as crops and agricultural waste.

Carbon released when many substances — particularly fossil fuels such as oil, gas, and coal — are burned by vehicles and planes; by the manufacturing processes of many consumer goods; and by the heating, cooling, and electricity for your home.

The amount of land needed to support a person’s consumption of goods and resources. It describes the amount of land required to farm a person’s food, mine their energy sources, transport their goods and services, and hold their waste.

The state of reducing a person’s carbon emissions as much as possible and balancing the remaining carbon emissions by offsetting them with processes that consume carbon.

Paying for or participating in programs that reduce the carbon in the atmosphere. Purchased “shares” go toward reducing the same amount of environmental costs that an activity expends. Carbon offset programs or projects often involve tree planting because trees have a huge capacity to absorb carbon from the atmosphere. Other programs involve everything from supporting solar and wind power to replacing fossil fuel–burning stoves in developing countries with more sustainable energy sources.

A cancer-causing substance.

Reducing the number of vehicles going to the same destination by having two or more people ride in the same vehicle. In most cases, carpoolers take turns being the driver and using their own vehicles.

A system in which a person pays a fee that gives them access to a vehicle (or a pool of vehicles), usually parked in an easily accessible location. Car-sharing can eliminate the need for a personal vehicle.

Changes in the concentrations of various gases in the atmosphere that are affecting the planet’s climate. Many scientists believe that the increase of carbon dioxide is a primary contributor to global warming, which occurs when gases trap warmth in the earth’s atmosphere instead of letting the atmosphere release it.

Fluorescent light bulbs that fit into a standard light bulb socket and use a fraction of the energy of their incandescent counterparts.

Decayed plants and other organic matter that breaks down into rich soil.

Principles adopted by a business to make sure that its operations harm no one and instead benefit everyone around it and involved in it.

Bringing natural light into a home.

A community of living organisms and nonliving materials.

Sustainable and ethical travel in a natural environment.

The federal government system for rating energy efficiency in appliances.

Federal agency that regulates environmental laws.

System to ensure that workers and producers receive fair value for their products and that mandates sustainable practices in producing those products.

The distance food travels from where it’s produced to the consumer.

The amount of land that various diets require to sustain them.

The energy-rich organic substances, traced back to the remains of organisms that lived 300 to 400 million years ago, that modern societies burn to provide power.

Energy within the Earth in the form of heat.

The warming of the planet caused by gases in the atmosphere trapping the sun’s heat instead of letting it get through to space. This action is very similar to what happens in a greenhouse.

Gases such as carbon dioxide, methane, and nitrous oxide produced by the burning and processing of fossil fuels and that contribute to global warming and acid rain.

Water already used for washing, laundry, or showering that is appropriate for household functions from toilet flushing to watering plants.

A scoring system to rate how ecologically friendly buildings are.

White or light-colored horizontal fins above windows that bounce sunlight up onto the ceiling to bring it deeper into the room.

A tiny semiconductor that emits light.

An energy source that burns cleaner than coal and oil but still releases carbon dioxide when it burns and methane during production, storage, and transportation.

Of living things; in food, grown without chemical fertilizers or pesticides or genetically modified organisms.

Building design that takes advantage of the fact that the summer sun is higher than the winter sun. Overhangs shade the building from the summer sun and allow the lower winter sun to enter the building and heat it.

Chemicals derived from petroleum.

Energy drawn by a plugged-in appliance even when the appliance is turned off.

A triangle with a number from 1 to 7 inside indicating what type of plastic an item is made from.

Collecting goods that have reached the end of their lives and processing them, their parts, or some of their parts, into the raw materials from which new goods are made.

Energy from sources that cannot be used up, such as wind, water, and the sun.

A rooftop window that brings in twice the light of a traditional window of the same size.

A panel containing cells that convert sunlight into electricity.

A passage that brings light into a room by bouncing sunlight through a small dome skylight on the roof connected to another skylight on the ceiling of the room. (Also known as a sun tube, sun pipe, and solar tube.)

Using natural resources in a way that allows for continued viability.

An opening such as a window that leaks heat and air-conditioning energy.

The ability of a material to absorb and store temperature.

The environmental practices of reducing consumption, reusing items, and recycling.

Disposed materials that can cause harm to people, animals, or the environment.

Landscaping for water conservation; a practice of garden planning and maintenance.