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The RTCC Climate Change A-Z

By RTCC Staff

Whether it’s climate science, the dense wordings of international emissions policy or the even denser world of the carbon economy, our A-Z is designed to be a quick go-to guide for the mystifying terms and acronyms that the sector relies on.

If all the talk of climate change is leaving you feeling a bit lost, hopefully our A-Z can put you back on the right path.

Just hit Ctrl + F and search the page for whatever you’re looking for. If you can’t find what you’re looking for, leave a comment at the bottom of the story and we’ll add it (within reason!). If you disagree with a definition or we’ve made an error, we welcome your (polite) feedback!

Climate Change A-Z

Adaptation – the process of adjusting behaviour and/or infrastructure in response to “new normals” created by shifting climatic patterns. In reality it means survival. In politics, discussions tend to focus on who should pay for adaptation projects in the developing world. (Entry suggested by Joachim Nibbe)

Aerosols – microscopic particles originating from both natural sources (e.g., volcanoes) and human activities (e.g., coal burning).

Afforestation – the planting of new forests on lands that have not been recently forested.

Albedo – the reflectivity of Earth. Unreflected light is converted to infrared radiation (i.e. heat), which causes atmospheric warming.

Alternative energy – energy derived from nontraditional sources (e.g. compressed natural gas, solar, hydroelectric, wind).

Anthropogenic – term used to describe something which is caused or produced by humans. We often talk of anthropogenic climate change.

Assigned Amount Units (AAU) – the individual credits, equivalent to one tonne of CO2 or equivalent emissions, traded under the Kyoto Protocol. The total number of AAUs makes up that country’s ‘allowed’ emissions in line with their own targets. Spares can be traded, extras must be purchased.

BINGO: Acronym used to describe Business and Industry Non-Governmental Organisations.

Bioenergy – Energy generated from biomass, wood, energy crops and organic wastes and residues. Traditional bioenergy includes fuelwood, charcoal, dung and other residues. Modern bioenergy or biofuels refer to biomass converted to higher value and more efficient and convenient energy carriers, such as pellets, biogas, biethanol and biodiesel. (See Biofuel and Biomass)

Biofuel – gas or liquid fuel made from plant material (biomass). Includes wood, wood waste, wood liquors, peat, railroad ties, wood sludge, spent sulfite liquors, agricultural waste, straw, tyres, fish oils, tall oil, sludge waste, waste alcohol, municipal solid waste, landfill gases, other waste, and ethanol typically blended into motor gasoline, shipping or aviation fuels

Biogas – usually refers to the product of waste to energy technologies. These can involve rotting organic waste, manure or specifically grown crops. As well as producing biogases that can be used directly for fuel or sold to the gas grid, the process also generates a nitrogen-rich fertiliser as a by-product.

Biomass – technically, the total dry organic matter or stored energy content of living organisms in a given area. Biomass refers to forms of living matter (e.g., grasses, trees) or their derivatives (e.g., ethanol, timber, charcoal) that can be used as fuels.

Biomass energy – energy produced by combusting biomass materials such as wood. The carbon dioxide emitted from burning biomass will not increase total atmospheric carbon dioxide if this consumption is done on a sustainable basis (i.e., if in a given period of time, regrowth of biomass takes up as much carbon dioxide as is released from biomass combustion). Biomass energy is often suggested as a replacement for fossil fuel combustion.

Black carbon – a greenhouse gas emitted during the burning of coal, diesel fuel, natural gas and biomass, it is part of the composition of soot. Black carbon has emerged as a major contributor to climate change, second only to carbon dioxide. Unlike CO2, black carbon only remains in the atmosphere for two to three weeks and is part of the group terms short-live climate forcers (SLCFs), and is often seen as a quick win in the fight to combat climate change.

BONGO - Acronym used to describe Business organised Non-Governmental Organisations.

Capital stock – existing investments in energy plant and equipment that may or may not be modified once installed.

Carbon cycle – general term used in reference to the sum of all reservoirs and flows of carbon on Earth. The flows tend to be cyclic in nature; for example, carbon removed from the atmosphere (one reservoir) and converted into plant tissue (another reservoir) is returned back into the atmosphere when the plant is burned.

Carbon dioxide (CO2) – A common gas formed by the combination of carbon and oxygen. A by product of the combustion of fossil fuels and a key component of the carbon cycle. It can trap heat within the earth’s atmosphere giving it a so-called “global warming potential”. All other greenhouse gases’ warming potentials are measured relative to CO2.

Carbon reservoir or sink – within the carbon cycle, the physical site at which carbon is stored (e.g., atmosphere, oceans, Earth’s vegetation and soils, and fossil fuel deposits).

Carbon sequestration – the uptake and storage of carbon. Trees and plants, for example, absorb carbon dioxide, release the oxygen and store the carbon. Fossil fuels were at one time biomass and continue to store the carbon until burned. See also Carbon sinks.

Certified Emissions Reduction (CER) – reductions of greenhouse gases achieved by a Clean Development Mechanism (CDM) project. A CER can be sold or counted toward Annex I countries’ emissions commitments. Reductions must be additional to any that would otherwise occur.

Chlorocarbon – a compound containing chlorine and carbon; examples include carbon tetrachloride and methyl chloroform, both of which are ozone depleters.

Chlorofluorocarbons (CFCs) – compounds containing chlorine, flourine, and carbon; they generally are used as propellants, refrigerants, blowing agents (for producing foam), and solvents. They are identified with numbered suffixes (e.g., CFC-11, CFC-12) which identify the ratio of these elements in each compound. They are known to deplete stratospheric ozone and also are greenhouse gases in that they effectively absorb outgoing infrared radiation in the atmosphere.

Climate – the average weather together with its variability of representations of the weather conditions for a specified area during a specified time interval (usually decades).

RTCC Guides 

Q&A: Climate Change and the Oceans

Q&A: Emissions Trading

Q&A: Kyoto Protocol

Climate change – changes in long-term trends in the average climate, such as changes in average temperatures. In IPCC usage, climate change refers to any change in climate over time, whether due to natural variability or as a result of human activity. In UNFCCC usage, climate change refers to a change in climate that is attributable directly or indirectly to human activity that alters atmospheric composition.

Cogeneration – the simultaneous generation of both electric power and heat; the heat, instead of being discharged without further use, is used in some fashion (e.g., in district heating systems).

Common But Differentiated Responsibility (CBDR) – A key but hotly contested principle that underpins the UN climate change convention and negotiations. Effectively means we all have a duty to protect our planet, but those who have contributed more to global Greenhouse Gas Emissions (developed and industrialised states) have a greater role to play. The logic also follows that those who have developed more also have better capabilities to cut their own emissions and help fellow nations to adapt.

Composting – is the small-scale rotting of organic material, typically food scraps and garden waste, in the presence of oxygen. The end product from composting can be used as a fertiliser and displaces chemical alternatives and peat use. When these materials are sent to landfill they become starved of oxygen and begin emitting methane and carbon dioxide as they decompose through a different chemical process. Composting results in greenhouse gas emission reductions because peat is a strong carbon sink and gases produced in landfill are avoided.

COP – or Conference of the Parties, refers to the annual meeting of signatories to the UN climate change treaty. They are typically followed by a number identifying their sequence. COP18 will be held in Doha in November 2012.

CO2e: “Carbon dioxide equivalents” is a unit of measurement that allows the effect of different greenhouse gases and other factors to be compared using carbon dioxide as a standard unit for reference.

Deforestation – converting forest land to other vegetation or uses (e.g., cropland, pasture, dams).

Desertification – the degradation of land in arid, semi-arid and sub-humid areas – commonly referred to as drylands – by a change in climate or destructive land use, creating desert-like conditions. It is estimated that a third of the world’s land surface is currently suffering from the effects of desertification.

Disaster Risk Reduction (DDR) – The process of reducing the damage caused by natural disasters and climate-induced extreme weather events. In many cases this can crossover with climate change adaptation strategies as “new normals” emerge. Work can involve fortifying mud buildings and raising structures to protect against floods or improving skills and knowledge for better water management to reduce the impact from drought cycles.

Ecosystem Services – Simply the benefits people derive from Ecosystems. Wildlife, flora and fauna pollinate crops, prevent soil erosion and purify water. Arguments continue over whether a value can be placed on these services.

Emissions – flows of gases, liquid droplets or solid particles into the atmosphere. Gross emissions from a specific source are the total quantity released. Net emissions are gross emissions minus flows back to the original source. Plants, for example, take carbon from the atmosphere and store it as biomass during photosynthesis, and they release it during respiration, when they decompose, or when they are burned.

Emission inventory – a list of air pollutants emitted into a community’s, a state’s, a nation’s, or Earth’s atmosphere in amounts per some unit time (e.g., day or year) by type of source. An emission inventory has both political and scientific applications.

Energy efficiency – the practice of reducing power consumption. Can apply to industry, transport, buildings or any other sector. Most commonly used in reference to improving building stock through better insulation to reduce heating and/or cooling requirements.

Environmental Impact – is the result of a human-induced change in the natural or built environment. The impact of infrastructure, industrial, energy or construction projects or processes will typically be scrutinised to assess whether the environmental costs are justified by the project’s benefits. Potential impacts include loss of a specific habitat, pollution of water and soils and many others.

Equivalent carbon dioxide (CO2e) – is a unit to measure combinations of different greenhouse gases in terms of the volume of CO2 required to create the same warming effect on the atmosphere. For example, one tonne of a greenhouse gas that had a warming effect 100 times greater than CO2, would be 100 tonnes CO2e.

Feedback loop – something that accelerates or decelerates a warming trend – a positive feedback accelerates a temperature rise, whereas a negative feedback decelerates it. For example melting ice reveals darker-coloured land or water beneath it, which absorbs more of the sun’s energy, leading to more warming which is turn leads to more ice melting.

Fluorocarbon – a compound containing fluorine and carbon; among these are chlorinated flourocarbons (CFCs) and brominated fluorocarbons (halons).

Forest – terrestrial ecosystem (biome) with enough average annual precipitation (at least 76 centimetres or 30 inches) to support growth of various species of trees and smaller forms of vegetation.

Fossil fuel – coal, petroleum, or natural gas or any fuel derived from them.

Global warming – the apparent recent trend of increasing world-surface and tropospheric temperatures, thought to be caused by pollutants, and their “entrapment” of heat. This phenomenon is popularly known as “the greenhouse effect.”

Global Warming Potential (GWP) – is the ability of a certain gas to warm the atmosphere during a given time period relative to the warming effect of CO2. CO2 is used as the baseline and so always has a global warming potential of one. If a greenhouse gas is 500 times more powerful than CO2, it would have a global warming potential of 500. GWP is typically measured for time periods of 20, 50 and 500 years.

Grandfathering – is when carbon emission credits are given to big industrial polluters, rather than auctioned off. The process can be unpopular as if too many credits are given, the recipient company has no incentive to reduce emissions. Divisive trading between firms given too few and too many can erode faith in carbon trading platforms.

Greenhouse effect – the effect produced as certain atmospheric gases allow incoming solar radiation to pass through to Earth’s surface, but prevent the outgoing (infrared) radiation, which is re-radiated from Earth, from escaping into outer space. The effect is responsible for warming the planet.

Greenhouse gas – any gas that absorbs infrared radiation in the atmosphere.

Hydrocarbon – a large class of organic chemicals made up of carbon atoms linked to hydrogen and, sometimes, oxygen. Hydrocarbons are used for fuel and other economically important materials. Hydrocarbons can be altered by the addition of other chemicals, such as halogens.

Hydrofluorocarbons (HFCs) – the group of chemicals that were used largely as the replacements to CFCs. While they do not damage the ozone layer, they have huge global warming potential, hundreds of times greater than CO2.

IPCC – The Intergovernmental Panel on Climate Change is a UN managed body that brings together climate science from around the world to inform policy makers. Its Assessment Reports are published (roughly) around every five years. While some recommendations such as the two degrees warming limit have become part of policy, not all do.

Indigenous – an object or person originating from and characteristic of a particular region or country. Used in the context of climate change mainly to describe groups of people – indigenous communities – but can also be used to describe species of plants or animals.

Joint Implementation – a project under-taken through the Kyoto Protocol (see below) between two countries with emissions limitation commitments. The donor party earns emission reductions units, eligible towards its Kyoto targets, by helping the other to cut carbon. The host country gains foreign investment and technology transfer.

Kyoto Protocol – The first binding deal on emissions reductions named after the host city of the 1997 UNFCCC meeting where it was signed. Rich countries agreed to enter into a carbon cap and trade system with targets on greenhouse gas cuts written into international law. The fate of a second phase of cuts based on the Kyoto rules remains undecided.

LULUCF – A term used in the UNFCCC negotiations, it refers to the greenhouse gas inventory covering emissions and removals of greenhouse gases from direct human-induced land use, land use change and forestry activities.  It is used in relation to the forestry and agriculture sector in the climate negotiations and covers emissions related to soils, trees, plants, biomass and timber.

Methane (CH4) – Another greenhouse gas also found commonly in nature. It is the most abundant gas in “natural gas”. It is also formed by rotting food in landfills, is a by-product of pastoral farming and can leak from natural stores during mining. It is 20 times more potent than CO2 in terms of its warming potential but has a shorter lifespan.

Mitigation – The process of limiting the effects of climate change and its severity by reducing emissions of greenhouse gases and attempting to draw down carbon held in the atmosphere into terrestrial-based storage such as vegetation or in the future, Carbon Capture and Storage (CCS) technologies. A big part of mitigation efforts is the transfer of funding and technologies that enable developing countries to leapfrog dirtier phases of development.

Nationally Appropriate Mitigation Action (NAMA) – NAMAs refer to a country’s response to reduce its greenhouse gas emissions. The pledges formed part of the Bali Roadmap at the UN talks in 2007 however none have yet been implemented. “Nationally Appropriate” is a reference to the idea that a country’s response should be within its capabilities and a reflection of its responsibilities for historical emissions. See CBDR.

National Adaptation Programmes of Action (NAPAs) – offer a process for the Least Developed Countries (LDCs) to identify priority activities that respond to their urgent and immediate needs to adapt to climate change. It highlights the activities which if delayed further would increase vulnerability and costs at a later stage.

Ozone – a molecule consisting of three bound atoms of oxygen. Its chemical nomenclature is O3. Most oxygen in the atmosphere, O2, consists of only two oxygen atoms.

Ozone layer – something of a misnomer, since ozone does not occur in a flat “layer” in the atmosphere. This term refers to ozone in the stratosphere where it occurs in its highest concentrations – roughly from 1 to 10 parts per million. This atmospheric zone lies between 15 and 50 kilometres above Earth’s surface, depending upon latitude, season, and other factors.

Plenary – a formal meeting of all Parties of the UNFCCC’s Conference of the parties (COP), or Meeting of Parties to the Kyoto Protocol (CMP) or one of the subsidiary bodies. Formal decisions or conclusions can only be made during these plenary sessions.

Quantified Emissions Limitation and Reduction Commitments (QELRO) – a binding schedule of emissions reductions or limitations made under the Kyoto Protocol by a particular country.

Radiation – electromagnetic energy, not to be confused with “radioactivity” (the emission of radiation, generally alpha or beta particles from the nucleus of an unstable isotope).

REDD – A UN programme which aims to reduce emissions from deforestation and forest degradation. It forms part of the UN’s climate change process, through the UNFCCC. (Post suggested by Thabit Jacob)

Resilience – This refers to the ability to withstand and recover quickly from the difficult conditions caused by the adverse effects of climate change (including related hazards and disasters). It can refer to both a human system – referring to its adaptive capacity – and natural systems – the amount of change an environment can undergo without being fundamentally altered. We often talk about the resilience of communities and/or businesses to climate change.

Sequestration – an opportunity to remove atmospheric CO2, either through biological processes (e.g. plants and trees), or geological processes through storage of CO2 in underground reservoirs.

Sinks – any process, activity or mechanism that results in the net removal of greenhouse gases, aerosols, or precursors of greenhouse gases from the atmosphere.

Source – any process or activity resulting in the net release of greenhouse gases, aerosols, or precursors of greenhouse gases into the atmosphere.

Stratosphere – the Earth’s atmosphere 10-50 km above the surface of the planet.

Subsidiary Body for Scientific & Tech. Advice (SBSTA) – a permanent body established by the UNFCCC that serves as a link between expert information sources such as the IPCC and the COP.

Substitution – the economic process of trading off inputs and consumption due to changes in prices arising from a constraint on greenhouse gas emissions.

Sustainable Development – development that aims to meet human needs while preserving the environment so that these needs can be met not only in the present but also for generations to come.

Targets and Timetables – the percent reduction from the 1990 emissions baseline that the country has agreed to. On average, developed countries agreed to reduce emissions by 5.2% below 1990 emissions during the period 2008-2012, the first commitment period.

Thermal expansion – expansion of the world’s oceans in response to global warming is considered the predominant driver of current and future sea-level rise.

Thermohaline Circulation (THC) – a three-dimensional pattern of ocean circulation driven by wind, heat and salinity that is an important component of the ocean-atmosphere climate system.

Trace gas – gases found in the Earth’s atmosphere other than nitrogen, oxygen, argon and water vapour. Carbon dioxide, methane, and nitrous oxide are classified as trace gases. Although trace gases taken together make up less than one percent of the atmosphere, carbon dioxide, methane and nitrous oxide are important in the climate system. Water vapour also plays an important role in the climate system; its concentrations in the lower atmosphere vary considerably from essentially zero in cold dry air masses to perhaps 4% by volume in humid tropical air masses.

Troposphere – the Earth’s atmosphere 0-10 km above the planet’s surface.

UN Framework Convention on Climate Change (UNFCCC) – a treaty signed at the 1992 Earth Summit in Rio de Janeiro that calls for the “stabilisation of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.” It took effect in March 1994 upon ratification by more than 50 countries.

Uncertainty – a prominent feature of the benefits and costs of climate change. Decision-makers need to compare risk of premature or unnecessary actions with risk of failing to take actions that subsequently prove to be warranted. This is complicated by potential irreversibilities in climate impacts and long-term investments.

Vector-borne disease – result from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples include Dengue fever, viral encephalitis, Lyme disease, and malaria.

Water Vapour – the primary gas responsible for the greenhouse effect. It is believed that increases in temperature caused by anthropogenic emissions of greenhouse gases will increase the amount of water vapour in the atmosphere, resulting in additional warming.

Weather – the short-term (i.e., hourly and daily) state of the atmosphere. Weather is not the same as climate.

X-ray – a photographic or digital image of the internal composition of an object, produced by X-rays being passed through it and being absorbed to different degrees by different materials. Often used by researchers to gain a better understanding of corals.

Youth – a group of young people. A very vocal constituency within the UNFCCC negotiations that generally includes people between the ages of 16 to 29.

Zeronauts – a concept devised by sustainability expert John Elkington whereby innovators and entrepreneurs lead the world towards zero population growth, emissions, poverty and pollution among others.

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