Environment
The complex of physical, chemical, and biotic factors (as climate, soil, and
living things) that act upon an organism (a living thing) or an ecological
community (a collection of living things) and ultimately determine its form
and survival. The circumstances, objects, and conditions that surround each
of us.
Fluorinated
gases
Powerful synthetic greenhouse gases such as hydrofluorocarbons,
perfluorocarbons, and sulfur hexafluoride that are emitted from a variety of
industrial processes. Fluorinated gases are sometimes used as substitutes for
stratospheric ozone-depleting substances (e.g., chlorofluorocarbons,
hydrochlorofluorocarbons, and halons) and are often used in coolants,
foaming agents, fire extinguishers, solvents, pesticides, and aerosol propellants. These gases are emitted in small quantities compared to carbon dioxide
(CO2), methane (CH4), or nitrous oxide (N2O), but because they are potent
greenhouse gases, they are sometimes referred to as high global warming
potential gases (high GWP gases).
Fluorocarbons
Carbon-fluorine compounds that often contain other elements such as hydrogen, chlorine, or bromine. Common fluorocarbons include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons
(HFCs), and perfluorocarbons (PFCs).
Forcing
Factors that affect the earth’s climate. For example, natural factors such as
volcanoes and human factors such as the emission of heat-trapping gases and
particles through fossil fuel combustion.
Fossil fuel
(a) A general term for a fuel that is formed in the earth from plant or animal
remains, including coal, oil, natural gas, oil shales, and tar sands. (b) A general
term for organic materials formed from decayed plants and animals that have
been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat
and pressure in the earth’s crust over hundreds of millions of years.
Glacier
(a) A very large body of ice moving slowly down a slope or valley or
spreading outward on a land surface. (b) A multiyear surplus accumulation
of snowfall in excess of snowmelt on land and resulting in a mass of ice at
least 0.1 km
2 in area that shows some evidence of movement in response to
gravity. A glacier may terminate on land or in water. Glacier ice is the largest
reservoir of fresh water on earth and second only to the oceans as the largest
reservoir of total water. Glaciers are found on every continent except
Australia.
Global average
temperature
An estimate of earth’s mean surface air temperature averaged over the entire
planet.
Global change
Changes in the global environment that may alter the capacity of the earth to
sustain life. Global change encompasses climate change, but it also includes
other critical drivers of environmental change that may interact with climate
change, such as land-use change, the alteration of the water cycle, changes in
biogeochemical cycles, and biodiversity loss.
Global climate
models (GCM)
Mathematical models that simulate the physics, chemistry, and biology that
influence the climate system.
Global warming
(a) The recent and ongoing global average increase in temperature near the
earth’s surface. (b) The observed increase in average temperature near the
earth’s surface and in the lowest layer of the atmosphere. In common usage,
“global warming” often refers to the warming that has occurred as a result of
increased emissions of greenhouse gases from human activities. Global
warming is a type of climate change; it can also lead to other changes in
climate conditions, such as changes in precipitation patterns.
Global warming
potential (GWP)
(a) A measure of the total energy that a gas absorbs over a particular period of
time (usually 100 years), compared to carbon dioxide. (b) A number that
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The complex of physical, chemical, and biotic factors (as climate, soil, and
living things) that act upon an organism (a living thing) or an ecological
community (a collection of living things) and ultimately determine its form
and survival. The circumstances, objects, and conditions that surround each
of us.
Fluorinated
gases
Powerful synthetic greenhouse gases such as hydrofluorocarbons,
perfluorocarbons, and sulfur hexafluoride that are emitted from a variety of
industrial processes. Fluorinated gases are sometimes used as substitutes for
stratospheric ozone-depleting substances (e.g., chlorofluorocarbons,
hydrochlorofluorocarbons, and halons) and are often used in coolants,
foaming agents, fire extinguishers, solvents, pesticides, and aerosol propellants. These gases are emitted in small quantities compared to carbon dioxide
(CO2), methane (CH4), or nitrous oxide (N2O), but because they are potent
greenhouse gases, they are sometimes referred to as high global warming
potential gases (high GWP gases).
Fluorocarbons
Carbon-fluorine compounds that often contain other elements such as hydrogen, chlorine, or bromine. Common fluorocarbons include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons
(HFCs), and perfluorocarbons (PFCs).
Forcing
Factors that affect the earth’s climate. For example, natural factors such as
volcanoes and human factors such as the emission of heat-trapping gases and
particles through fossil fuel combustion.
Fossil fuel
(a) A general term for a fuel that is formed in the earth from plant or animal
remains, including coal, oil, natural gas, oil shales, and tar sands. (b) A general
term for organic materials formed from decayed plants and animals that have
been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat
and pressure in the earth’s crust over hundreds of millions of years.
Glacier
(a) A very large body of ice moving slowly down a slope or valley or
spreading outward on a land surface. (b) A multiyear surplus accumulation
of snowfall in excess of snowmelt on land and resulting in a mass of ice at
least 0.1 km
2 in area that shows some evidence of movement in response to
gravity. A glacier may terminate on land or in water. Glacier ice is the largest
reservoir of fresh water on earth and second only to the oceans as the largest
reservoir of total water. Glaciers are found on every continent except
Australia.
Global average
temperature
An estimate of earth’s mean surface air temperature averaged over the entire
planet.
Global change
Changes in the global environment that may alter the capacity of the earth to
sustain life. Global change encompasses climate change, but it also includes
other critical drivers of environmental change that may interact with climate
change, such as land-use change, the alteration of the water cycle, changes in
biogeochemical cycles, and biodiversity loss.
Global climate
models (GCM)
Mathematical models that simulate the physics, chemistry, and biology that
influence the climate system.
Global warming
(a) The recent and ongoing global average increase in temperature near the
earth’s surface. (b) The observed increase in average temperature near the
earth’s surface and in the lowest layer of the atmosphere. In common usage,
“global warming” often refers to the warming that has occurred as a result of
increased emissions of greenhouse gases from human activities. Global
warming is a type of climate change; it can also lead to other changes in
climate conditions, such as changes in precipitation patterns.
Global warming
potential (GWP)
(a) A measure of the total energy that a gas absorbs over a particular period of
time (usually 100 years), compared to carbon dioxide. (b) A number that
28
L. K. Wang et al.