Education
Austin Climate Protection Plan (ACPP) Glossary
A | B | C | D | E | F | G | H | I | J | K | L | M
N | O | P | Q | R | S | T | U | V | W | X | Y | Z
A
Aerosol: A collection of airborne solid or liquid particles residing in the atmosphere for several hours. Aerosols may be of either natural or anthropogenic (caused by humans) origin. Aerosols may influence climate in two ways: directly through scattering and absorbing radiation, and indirectly through acting as catalyzing cloud formation or modifying the properties and lifetime of clouds. The term has also come to be associated, erroneously, with the propellant used in aerosol sprays.
Adaptation: Adjustment in natural or human systems to a new or changing environment.
Adaptive Capability: Ability of a natural or human system to respond to a changing environment or other natural and man-made stressors.
Afforestation: Planting of new forests on lands that historically have not contained forests.
Alternative Energy: Energy derived from nontraditional sources (e.g., compressed natural gas, solar, hydroelectric, wind).
Atmosphere: The gaseous envelope surrounding the Earth.
B
Biosphere: The part of the Earth system comprising all ecosystems and living organisms, in the atmosphere, on land or in the oceans.
Borehole: Any exploratory hole drilled into the Earth or ice to gather geophysical data. Climate researchers often take ice core samples, a type of borehole, to analyze atmospheric composition in earlier years.
C
Carbon Dioxide (CO2): A naturally occurring gas, and also a by-product of burning fossil fuels and biomass, as
well as land-use changes and other industrial processes. It is the principal anthropogenic
greenhouse gas that affects the Earth's radiative balance. It is the reference gas against
which other greenhouse gases are measured.
Climate: Climate is narrowly defined as the "average weather," or more in depth, as the statistical description in terms of the mean and variability of relevant atmospheric conditions over a period of time ranging from months to thousands of years. The classical period is 3 decades, as defined by the World Meteorological Organization (WMO). These quantities are most often surface variables such as temperature, precipitation, and wind.
Climate Change:
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).
Climate change may result from:
- Natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun;
- Natural processes within the climate system (e.g. changes in ocean circulation);
- Human activities that change the atmosphere's composition (e.g. through burning fossil fuels) and the land surface (e.g. deforestation, reforestation, urbanization, desertification, etc.)
Climate Feedback:
An interaction mechanism between processes in the climate system is called a climate
feedback, when the result of an initial process triggers changes in a second process that in
turn influences the initial one. A positive feedback intensifies the original process, and a
negative feedback reduces it.
Climate Lag: The delay that occurs in climate change as a result of some factor that changes only very slowly. For example, the effects of releasing more carbon dioxide into the atmosphere may not be known for some time because a large fraction is dissolved in the ocean and only released into the atmosphere many years later.
Concentration: Amount of a chemical in a particular volume or weight of air, water, soil, or other medium.
D
Deforestation: Those practices or processes that result in the conversion of forested lands for non-forest uses. This is often cited as one of the major causes of the greenhouse effect for two reasons:
- The burning of the wood releases carbon dioxide; and
- Trees that once removed carbon dioxide from the atmosphere in the process of photosynthesis are no longer present.
Desertification: The transformation of arable or habitable land to desert, by climatic change, human influence, or both.
E
Emissions: The release of a substance (usually a gas when referring to the subject of climate change) into the atmosphere.
Emissions Factor: A unique value for scaling emissions to activity data in terms of a standard rate of emissions per unit of activity (e.g., grams of carbon dioxide emitted per barrel of fossil fuel consumed).
Enhanced Greenhouse Effect: The concept that the natural greenhouse effect has been enhanced by anthropogenic emissions of greenhouse gases. Increased atmospheric concentrations of carbon dioxide, methane, nitrous oxide, chlorofluorocarbons (CFCs), and other gases caused by human activities such as fossil fuel consumption, trap more infra-red radiation, hereby exerting a warming influence on the climate.
F
Forcing Mechanism:
A process that alters the energy balance of the climate system, i.e. changes the relative
balance between incoming solar radiation and outgoing infrared radiation from Earth.
Such mechanisms include: changes in solar irradiance, volcanic eruptions, and
enhancement of the natural greenhouse effect by emissions of greenhouse gases.
G
Global Warming: Global warming is an average increase in the atmospheric temperature near the Earth's surface, which can contribute to changes in global climate patterns. Global warming can occur from a variety of causes, both natural and human induced. In common usage,"global warming" often refers to the warming that occurs as a result of increased emissions of greenhouse gases from human activities.
Greenhouse Effect: Trapping and build-up of heat in the atmosphere near the Earth’s surface. Some of the heat flowing back toward space from the Earth's surface is absorbed by water vapor, carbon dioxide, ozone, and several other gases in the atmosphere and then emit back toward the Earth’s surface. If the atmospheric concentrations of these greenhouse gases increase, the average temperature of the lower atmosphere will gradually increase.
Greenhouse Gas (GHG): Any gas that absorbs infrared radiation in the atmosphere. Greenhouse gases include, but are not limited to, water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbons (CFCs), and ozone (O3).
H
Hydrocarbons: Substances containing only hydrogen and carbon. Fossil fuels are hydrocarbons.
Hydrosphere: The component of the climate system comprising liquid surface and subterranean water, such as: oceans, seas, rivers, fresh water lakes, underground water etc.
I
Ice Core: A cylindrical section of ice removed from a glacier or an ice sheet in order to study climate patterns of the past. By performing chemical analyses on the air trapped in the ice, scientists can estimate Earth’s temperature as well as the percentage of carbon dioxide and other trace gases in the atmosphere at a given time.
Intergovernmental Panel on Climate Change (IPCC): The IPCC is an international group of scientists set up by the world metrological
organization and the United Nations Environmental Programme (UNEP). Its primary
goal is to provide “an objective source of information about the causes of climate
change.”
L
Landfill: Land waste disposal site in which waste is generally spread in thin layers, compacted, and covered with a fresh layer of soil each day.
M
Methane (CH4):
A hydrocarbon that is a greenhouse gas with a global warming potential most recently
estimated at 23 times that of carbon dioxide (CO2). Methane is produced through
decomposition of waste in landfills, animal digestion, decomposition of animal wastes,
production and distribution of natural gas and petroleum, coal production, and incomplete
fossil fuel combustion.
Metric Ton (Tonne): Common international measurement for the quantity of greenhouse gas emissions. A metric ton is equal to 2205 lbs or 1.1 short tons.
N
Natural Gas: Underground deposits of gases consisting of 50 to 90 percent methane (CH4) and small amounts of heavier gaseous hydrocarbon compounds such as propane (C3H8) and butane (C4H10).
Nitrogen Oxides (NOx):
Gases consisting of one molecule of nitrogen and varying numbers of oxygen molecules.
Nitrogen oxides are produced in vehicle exhaust emissions and from power stations. In
the atmosphere, nitrogen oxides can contribute to formation of photochemical ozone
(smog), can impair visibility, and have health consequences; they are thus onsidered
pollutants.
Nitrous Oxide (N2O): A powerful greenhouse gas with a global warming potential of 296 times that of carbon dioxide. Major sources of nitrous oxide include soil cultivation practices, especially the use of commercial and organic fertilizers, fossil fuel combustion, nitric acid production, and biomass burning.
O
Ozone Layer:
The layer of ozone that begins approximately 15 km above Earth and thins to an almost
negligible amount at about 50 km. this layer shields the Earth from harmful ultraviolet
radiation from the sun. Natural events such as volcanic eruptions and solar flares can
produce changes in ozone concentration, but man-made changes are of the greatest
concern.
P
Photosynthesis: The process by which plants take CO2 from the air (or bicarbonate in water) to build carbohydrates, releasing Oxygen in the process. There are several pathways of photosynthesis with different responses to atmospheric CO2 concentrations.
R
Radiation: The complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and absorbed by another body.
Recycling: Collecting and reprocessing a resource so it can be used again. An example is collecting aluminum cans, melting them down, and using the aluminum to make new cans or other aluminum products.
Reforestation: Planting of forests on lands that have previously contained forests but that had been converted to some other use.
S
Sink: Any process, activity, or mechanism which removes a greenhouse gas, an aerosol, or a precursor of a greenhouse gas or aerosol from the atmosphere.
T
Trace Gas: Any one of the less common gases found in the Earth's atmosphere. Nitrogen, oxygen, and argon make up more than 99 percent of the Earth's atmosphere. Other gases, such as carbon dioxide, water vapor, methane, oxides of nitrogen, ozone, and ammonia, are considered trace gases. Although relatively unimportant in terms of their absolute volume, they have significant effects on the Earth's weather and climate.
U
United Nations Framework Convention on Climate Change (UNFCCC):
The Convention on Climate Change sets an overall framework for intergovernmental
efforts to tackle the challenge posed by climate change. It recognizes that the climate
system is a shared resource whose stability can be affected by industrial and other
emissions of carbon dioxide and other greenhouse gases. The Convention enjoys near
universal membership, with 189 countries having ratified.
Under the Convention, governments:
- Gather and share information on greenhouse gas emissions, national policies and best practices.
- Launch national strategies for addressing greenhouse gas emissions and adapting to expected impacts, including the provision of financial and technological support to developing countries.
- Cooperate in preparing for adaptation to the impacts of climate change.
The Convention entered into force on 21 March 1994. The United States of America has signed but not ratified the Convention and is the only industrialized nation not part of the Convention.
W
Wastewater: Water that has been used and contains dissolved or suspended waste materials.
Water Vapor: The most abundant greenhouse gas, it is the water present in the atmosphere in gaseous form. Water vapor is an important part of the natural greenhouse effect.
