Produced or brought about by living organisms.

Global Warming Potential (GWP)

An index (i.e., a relative measure) of how much heat a greenhouse gas traps in the atmosphere over a chosen time horizon, relative to that of carbon dioxide. The GWP represents the combined effect of the differing times these gases remain in the atmosphere and their relative effectiveness in absorbing outgoing thermal infrared radiation. Although the most common time horizon is 100 years, GWP have been reported also for time horizons of 20 years and 500 years.

Green Manure

A fertilizer consisting of growing plants that are plowed back into the soil.

Greenhouse Gas (GHG)

Any of the atmospheric gases, both natural and anthropogenic, that contribute to the greenhouse effect by absorbing infrared radiation produced by solar warming of the Earth's surface. Water vapor (H2O), carbon dioxide (CO2), methane (CH4), nitrous oxide (NO2) and ozone (O3) are the primary greenhouse gases in the atmosphere.

Greenhouse Gas Effect

Heat trapping effect of greenhouse gases in the troposphere (lowest portion of the earth's atmosphere)


A human intervention to reduce the human impact on the climate system; it includes strategies to reduce greenhouse gas sources and emissions and enhancing greenhouse gas sinks (Source: EPA Glossary).


One trillion (1x1012) grams = one million 1x106) metric tons (see Units of Mass in Metric System).