ANNEX AGLOSSARY

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ABOVEGROUND BI OMASSAll living biomass above the soil including stem, stump, branches, bark, seeds, and foliage.
Note: In cases where forest understorey is a relatively small component of the aboveground biomass carbon
pool, it is acceptable for the methodologies and associated data used in some tiers to exclude it, provided the tiers
are used in a consistent manner throughout the inventory time series as specified in Chapter 5.

ABSOLUTE ERROR
Maximum tolerable error which is defined as an actual range independent of the value of the variable being estimated.

ACTIVITYA practice or ensemble of practices that take place on a delineated area over a given period of time.

ACCOUNTING
The rules for comparing emissions and removals as reported with commitments.

ACCURACY
Inventory definition: Accuracy is a relative measure of the exactness of an emission or removal estimate.
Estimates should be accurate in the sense that they are systematically neither over nor under true emissions or
removals, so far as can be judged, and that uncertainties are reduced so far as is practicable. Appropriate
methodologies conforming to guidance on good practices should be used to promote accuracy in inventories.
(FCCC/SBSTA/1999/6/Add. 1)
Statistical definition: Accuracy is a general term which describes the degree to which an estimate of a quantity
is unaffected by bias due to systematic error. It should be distinguished from precision as illustrated below.

ACTIVITY DATA
Inventory definition: Data on the magnitude of human activity resulting in emissions or removals taking place
during a given period of time.
In the LULUCF sector, data on land areas, management systems, lime and fertilizer use are examples of activity data.

AFFORESTATION 1
The direct human-induced conversion of land that has not been forested for a period of at least 50 years toforested land through planting, seeding and/or the human-induced promotion of natural seed sources.
1

In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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ANTHROPOGENIC
Man-made, resulting from human activities. In the IPCC Guidelines, anthropogenic emissions are distinguishedfrom natural emissions. Many of the greenhouse gases are also emitted naturally. It is only the man-madeincrements over natural emissions which may be perturbing natural balances.
In this LULUCF-GPG, all emissions and removals of managed lands are seen as anthropogenic.

ARITHMETI C MEAN
Statistical definition: The sum of the values divided by the number of values.

BASIC WOOD DENSITY
Ratio between oven dry mass and fresh stem-wood volume without bark. It allows the calculation of woody
biomass in dry matter mass.

BELOWGROUND BIOMASSAll living biomass of live roots. Fine roots of less than (suggested) 2mm diameter are sometimes excluded
because these often cannot be distinguished empirically from soil organic matter or litter.

BIAS
Inventory definition: A systematic error of the observation method, whose value in most cases is unknown. It
can be introduced by using measuring equipment that is improperly calibrated, by selecting items from a wrong
population or by favouring certain elements of a population, etc.

BIOMASS
Organic material both aboveground and belowground, and both living and dead, e.g., trees, crops, grasses, tree
litter, roots etc. Biomass includes the pool definition for above - and below - ground biomass.

BIOMASS ACCUMULATIO N RATESNet build up of biomass, i.e., all increments minus all losses. When carbon accumulation rate is used, only one
further conversion step is applied: i.e., the use of 50% carbon content in dry matter (default value).
The biomass accumulation rates can be calculated using Equation 3.2.4 in Chapter 3 of this report.

BIOMASS EXPANSI ON FACTOR (BEF)
A multiplication factor that expands growing stock, or commercial round-wood harvest volume, or growing
stock volume increment data, to account for non-merchantable biomass components such as branches, foliage,
and non-commercial trees.

BACK-CASTING
The opposite of forecasting. Predicting conditions in the past from current conditions.

BOREALSee polar/boreal.

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BOTTOM-UP MODELLING
A modelling approach which starts from processes at a detailed scale (i.e., plot/stand/ecosystems scale) andprovides results at a larger, aggregated scale (regional/national/continental/global).

BURNING/FIRE CO MPLETENESS
The share of the total amount of biomass in a given unit or area which burns in a fire. Often used in combination
with combustion efficiency.

CANOPY COVER
The percentage of the ground covered by a vertical projection of the outermost perimeter of the natural spread of
the foliage of plants. Cannot exceed 100%. (Also called crown closure)Same as crown cover.

CARBON ACCUMULATION RATES
See biomass accumulation rates.

CARBON BUDGETThe balance of the exchanges of carbon between carbon pools or between one specific loops (e.g., atmosphere –biosphere) of the carbon cycle. The examination of the budget of a pool or reservoir will provide information
whether it is acting as a source or a sink.

CARBON CYCLE
All parts (pools) and fluxes of carbon; usually thought of as a series of the four main pools of carbon
interconnected by pathways of exchange. The four pools are atmosphere, biosphere, oceans and sediments.
Carbon exchanges from pool to pool by chemical, physical and biological processes.

CARBON FLUX
Transfer of carbon from one pool to another in units of measurement of mass per unit of area and time (e.g.,tonnes C ha-1 yr-1).

CARBON POOL
The reservoir containing carbon.

CARBON RESERVE
Prefer to use carbon stock. See carbon stock.

CARBON STOCK
The quantity of carbon in a pool.

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CARBON STOCK CHANGE
The carbon stock in a pool can change due to the difference between additions of carbon and losses of carbon.
When the losses are larger than the additions, the carbon stock becomes smaller, and thus the pool acts as a source
to the atmosphere; when the losses are smaller than the additions, the pools acts as a sink to the atmosphere.

CLOSED FORESTS
Forests characterised by canopy cover higher than 40%.

CARBON DIOXI DE EQUIVALENT
A measure used to compare different greenhouse gases based on their global warming potentials (GWPs). The
GWPs are calculated as the ratio of the radiative forcing of one kilogramme greenhouse gas emitted to theatmosphere to that from one kilogramme CO2 over a period of time (usually 100 years).

CENSUS
Data collected by interrogation of (human) population. Usually the total population of interest is interviewed (butsometimes sampled).

CHRONOSEQUENCE
Chronosequences consist of measurements taken from similar but separate locations that represent a temporalsequence in land use or management, for example, years since deforestation. Efforts are made to control all otherbetween-site differences (e.g., by selecting areas with similar soil type, topography, previous vegetation).
Chronosequences are often used as a surrogate for experimental studies or measurements repeated over time at
the same location.

COEFFICIENT OF VARI ATION
Statistical definition: The coefficient of variation, vx is the ratio of the population standard deviation, σx, andmean, µx, where vx = σx /µx. It also frequently refers to the sample coefficient of variation, which is the ratio of
the sample standard deviation and sample mean.2

COMBUSTION EFFICIENCY
The fraction of the combusted carbon that is released in the form of CO2.

COMMERCI AL HARVEST
See fellings.

COMPARABILITY
Inventory definition: Comparability means that estimates of emissions and removals reported by Parties ininventories should be comparable among Parties. For this purpose, Parties should use the methodologies andformats agreed by the Conference of the Parties (COP) for estimating and reporting inventories.

2‘Coefficient of variation’ is the term, which is frequently replaced by ‘error’ in a statement like ‘the error is 5%’.

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COMPLETENESS
Inventory definition: Completeness means that an inventory covers all sources and sinks for the full geographic
coverage, as well as all gases included in the IPCC Guidelines in addition to other existing relevant source/sink
categories which are specific to individual Parties (and therefore may not be included in the IPCC Guidelines).

CONFIDENCE
Inventory definition: The term ‘confidence’ is used to represent trust in a measurement or estimate. Having
confidence in inventory estimates does not make those estimates more accurate or precise; however, it will
eventually help to establish a consensus regarding whether the data can be applied to solve a problem. This usageof confidence differs substantially from the statistical usage in the term confidence interval.

CONFIDENCE INTERVAL
Statistical definition: A confidence interval is the range in which it is believed that the true value of a quantity
lies. The level of belief is expressed by the probability, whose value is related to the size of the interval. It is oneof the ways in which uncertainty can be expressed (see estimation, statistical definition).
In practice a confidence interval is defined by a probability value, say 95%, and confidence limits on either sideof the mean value x. In this case the confidence limits L1 and L2 would be calculated from the probability density
function such that there was a 95% chance of the true value of the quantity being estimated by x lying between
L1 and L2. Commonly L1 and L2 are the 2.5 percentile and 97.5 percentile respectively.
Example: ‘An emission is between 90 and 100 kt with a probability of 95%.’ Such a statement can be provided
when the confidence interval is calculated (the numerical values in this example are arbitrarily chosen).

CONFUSION MATRI X
The conventional technique that establishes a matrix showing, for any given classification of land, theprobability of misclassification by one of the other candidate classifications.

CONSISTENCY
Inventory definition: Consistency means that an inventory should be internally consistent in all its elements
over a period of years. An inventory is consistent if the same methodologies are used for the base year and all
subsequent years and if consistent data sets are used to estimate emissions or removals from sources or sinks.
Under certain circumstances referred to in paragraphs 10 and 11 of FCCC/SBSTA/1999/6/Add.1, an inventory
using different methodologies for different years can be considered to be consistent if it has been recalculated ina transparent manner taking into account any good practices.
Statistical definition: A statistical estimator for a parameter is said to be consistent, if the estimator tends
towards the parameter as the size of the sample used for the estimator increases – i.e., precision is improved byan increasing number of observations.

CONVERSION
Change of one land use to another.

CORRELATION
Statistical definition: Mutual dependence between two quantities. See correlation coefficient.

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CORRELATION CO EFFICIENT
Statistical definition: A number lying between –1 and +1, which measures the mutual dependence between two
variables which are observed together. A value of +1 means that the variables have a perfect direct straight line
relation; a value of –1 means that there is a perfect inverse straight line relation; and a value of 0 means that
there is no straight line relation. It is defined as the covariance of the two variables divided by the product of
their standard deviations.

COUNTRY-SPECIFI C DATA
Data for either activities or emissions that are based on research carried out on domestic sites.

COVARIANCE
Statistical definition: The covariance between two variables is a measure of the mutual dependence between two
variables.
The sample covariance of paired samples of random variables X and Y is calculated using the following formula:
1 n
2
s xy
= ∑ ( x i − x )( y i − y ) where xi, yi, i = 1,…,n are items in the sample and x and y are sample means.
n i

CROPLANDThis category includes arable and tillage land, and agro-forestry systems where vegetation falls below thethreshold used for the forest land category, consistent with the selection of national definitions.

CROPLAND MANAGEMENT 3
The system of practices on land on which agricultural crops are grown and on land that is set aside or
temporarily not being used for crop production.

CROSS- CUTTI NG ISSUES
Matters that arise in more than one part of the good practice guidance. In this report identifying and quantifying
uncertainties, sampling, methodological choice – identification of key categories, quality assurance and quality control,
time series consistency and recalculation, and verification are addressed in a separate chapter called “Cross-cutting
Issues”.

CROWN COVER
See canopy cover.

DEAD WOOD
Includes all non-living woody biomass not contained in the litter, either standing, lying on the ground, or in thesoil. Dead wood includes wood lying on the surface, dead roots, and stumps larger than or equal to 10 cm indiameter or any other diameter used by the country.

3

In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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DECISION TREEInventory definition: A decision tree is a flow chart describing the specific ordered steps which need to befollowed to develop an inventory or an inventory component in accordance with the principles of good practice.

DEFORESTATION 4
The direct human-induced conversion of forested land to non-forested land.

DISTURBANCES
Processes that reduce or redistribute carbon pools in terrestrial ecosystems.

DRY (FOREST)
Moisture regimes for boreal and temperate zones are defined by the ratio of mean annual precipitation (MAP)and potential evapotranspiration (PET): Dry (MAP/PET < 1) and Wet (MAP/PET > 1); and for tropical zones by
precipitation alone: Dry (MAP < 1,000 mm), Moist (MAP: 1,000-2,000 mm) and Wet (MAP > 2,000 mm).

DRY BIOMASS
See dry matter.

DRY MATTER ( d.m. )Dry matter refers to biomass that has been dried to an oven-dry state, often at 70ºC.

EMISSIONS
The release of greenhouse gases and/or their precursors into the atmosphere over a specified area and period of time.

EMISSION FACTOR
Inventory definition: A coefficient that relates the activity data to the amount of chemical compound which isthe source of later emissions. Emission factors are often based on a sample of measurement data, averaged todevelop a representative rate of emission for a given activity level under a given set of operating conditions.

ERROR
Statistical definition: In statistical usage, the term ‘error’ is a general term referring to the difference between
an observed (measured) value of a quantity and its ‘true’ (but usually unknown) value and does not carry the(pejorative) sense of a mistake or blunder.

ERROR MATRI X
See confusion matrix.

4

In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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ESTIMATION
Inventory definitions: The process of calculating emissions.
Statistical definition: Estimation is the assessment of the value of a quantity or its uncertainty through theassignment of numerical observation values in an estimation formula, or estimator. The results of an estimation
can be expressed as follows:••a point estimation which provide a number which can be used as an approximation to a parameter (such as
the sample standard deviation which estimates the population standard deviation), or
an interval estimate specifying a confidence level.

Example: A statement like ‘The total emission is estimated to be 100 kt and its coefficient of variation is 5%’ is based
upon point estimates of the sample mean and standard deviation, whereas a statement such as ‘The total emission lies
between 90 and 110 kt with probability 95%’ expresses the results of estimation as a confidence interval.

EXPERT JUDGEMENT
Inventory definition: A carefully considered, well-documented qualitative or quantitative judgement made in
the absence of unequivocal observational evidence by a person or persons who have a demonstrable expertise in
the given field.

EXTREME VALUE
Statistical definition: The extreme values of a sample are the maximum and minimum values of the sample.
The statistical theory of extreme values is concerned with estimating the distributions of these extreme values forlarge numbers of sampled values.

FELLINGSStanding volume of all trees live or dead, measured overbark to a specified minimum diameter at breast heightthat are felled during the reference period, including those parts of trees that are not removed from the forest.
Removals are a subset of fellings (the commercial part destined for processing).

FERMENTED HORI ZO N (F)A horizon consisting of partly decomposed litter in which macroscopically recognisable parts of plants remain.
Fine organic matter, consisting of macro-fauna excrements is almost always existing, but is less in substancethan the recognisable plant material.

FOREST 5
Forest is a minimum area of land of 0.05 – 1.0 hectares with tree crown cover (or equivalent stocking level) of
more than 10 – 30 per cent with trees with the potential to reach a minimum height of 2 – 5 metres at maturity insitu. A forest may consist either of closed forest formations where trees of various storeys and undergrowthcover a high portion of the ground or open forest. Young natural stands and all plantations which have yet toreach a crown density of 10 – 30 per cent or tree height of 2 – 5 metres are included under forest, as are areas
normally forming part of the forest area which are temporarily unstocked as a result of human intervention suchas harvesting or natural causes but which are expected to revert to forest.
Remark: Forests are not defined for reporting under the Convention. The IPCC Guidelines encourage countries
to use detailed ecosystem classifications in the calculations and in reporting broad specified categories to ensure
consistency and comparability of national data across countries.

5

In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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FOREST I NVENTORY
System for measuring the extent, quantity and condition of a forest, usually by sampling.

FOREST LANDThis category includes all land with woody vegetation consistent with thresholds used to define forest land in thenational GHG inventory, sub-divided at the national level into managed and unmanaged and also by ecosystem
type as specified in the IPCC Guidelines.6 It also includes systems with vegetation that currently falls below, but
is expected to exceed, the threshold of the forest land category.

FOREST MANAGEMENT 7
A system of practices for stewardship and use of forest land aimed at fulfilling relevant ecological (including
biological diversity), economic and social functions of the forest in a sustainable manner.

GOOD PRACTI CE
Inventory definition: Good Practice is a set of procedures intended to ensure that greenhouse gas inventories
are accurate in the sense that they are systematically neither over nor underestimates so far as can be judged, andthat uncertainties are reduced so far as possible.
Good Practice covers choice of estimation methods appropriate to national circumstances, quality assurance andquality control at the national level, quantification of uncertainties and data archiving and reporting to promotetransparency.

GRASSLANDThis category includes rangelands and pasture land that is not considered as cropland. It also includes systems
with vegetation that fall below the threshold used in the forest land category and is not expected to exceed,
without human intervention, the thresholds used in the forest land category. This category also includes all
grassland from wild lands to recreational areas as well as agricultural and silvo-pastural systems, subdivided into
managed and unmanaged, consistent with national definitions.

GRAZING LAND MANAGEMENT 8
The system of practices on land used for livestock production aimed at manipulating the amount and type ofvegetation and livestock produced.

GRID CELL
The unit of land defined by the boundaries of an imaginary grid imposed on a map. May also be called a raster
cell or a pixel.

GROSS ANNUAL I NCREMENT
The average annual increment of volume over the reference period of all trees measured to a specified minimum
diameter at breast height (varies by country). Includes increment of trees which have been felled or die.
6

Forest management has particular meaning under the Marrakesh Accords, which may require subdivision of the managed
forest as described in Chapter 4.
7
In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.
8
In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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GROUND TRUTH
A term used for data obtained by measurements on the ground, usually as validation for, e.g., satellite data.

GROWING STOCK
The living tree component of the standing volume (measured in m3 overbark).

HIGH ACTIVI TY CLAY (HAC) SOILS
Soils with high activity clay (HAC) minerals are lightly to moderately weathered soils which are dominated by
2:1 silicated clay minerals (in FAO classification included: Vertisols, Chernozems, Phaezems, Luvisols).

HARMONISATION OF DEFINITIONSIn this context it is meant to standardize or to increase comparability and/or convergence between definitions.

HUMUS HORI ZO N ( H)
Horizon consisting by far of finely distributed organic matter (but still on top of the mineral soil horizons).
Macroscopically recognisable parts of plants remain, but occur to much lesser extent than the finely distributedorganic matter. The horizon can contain mineral soil particles.

INCREMENT
See gross and net annual increment.

INVENTORIES CONSISTENT WITH GO OD PRACTICE
Those inventories which contain neither over- nor underestimates so far as can be judged, and in which
uncertainties are reduced as far as is practicable.

IMPROVED PASTURES/ GRASSLAND/ RANGELAND
Land subject to intensive, controlled grazing often subject to fertilisation and/or regular re-establishment of thegrass cover.

KEY CATEGORY
A category that is prioritised within the national inventory system because its estimate has a significant influence
on a country’s total inventory of direct greenhouse gases in terms of the absolute level of emissions, the trend inemissions, or both.

KEY SOURCE
See key category.

LAND COVER
The type of vegetation covering the earth’s surface.

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LAND USE
The type of activity being carried out on a unit of land.
In GPG-LULUCF this term is used for the broad land-use categories defined in Chapter 2. It is recognized thatthese land categories are a mixture of land cover (e.g,, Forest, Grassland, Wetlands) and land use (e.g., CroplandSettlements) classes.

LFH LAYERS
Soil horizons. For details see individual definitions under litter horizon, fermented horizon and humus horizon.

LITTER
Includes all non-living biomass with a diameter less than a minimum diameter chosen by the country (forexample 10 cm), lying dead, in various states of decomposition above the mineral or organic soil. This includes
litter, fumic, and humic layers. Live fine roots (of less than the suggested diameter limit for belowgroundbiomass) are included in litter where they cannot be distinguished from it empirically.

LITTER HORI ZON ( L)A horizon consisting of relatively fresh dead plant material, it may be colourised, but does not containexcrements from soil fauna. It is not or only partly fragmented.

LOGNORMAL DISTRIBUTION
Statistical definition: The lognormal distribution is an asymmetric distribution, which starts from zero, rises toa maximum and then tails off more slowly to infinity. It is related to the normal distribution: X has a lognormal
distribution if ln (X) has a normal distribution.

The PDF of the lognormal distribution is given by:f ( x) =−1

σ l x 2π(ln x − µ l ) 2

e

2σ l2

, for 0 ≤ x ≤ ∞ .

The parameters required to specify the function are: µl the mean of the natural log transform of the data; and σl 2
the variance of the natural log transform of the data. The data and information that the inventory compiler canuse to determine the input parameters are: mean = µ; variance = σ 2; and the relationships:µ l = lnµ2
(σ 2 + µ 2 )

and

σl =

σ 2

ln  2 + 1 .
µ




LOW ACTIVI TY CLAY (LAC) SOILS
Soils with low activity clay (LAC) minerals are highly weathered soils dominated by 1:1 clay mineral andamorphous iron and aluminium oxides (in FAO classification included: Acrisols, Nitosols, Ferrasols).

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MANAGED FOREST
All forests subject to some kind of human interactions (notably commercial management, harvest of industrial
round-wood (logs) and fuelwood, production and use of wood commodities, and forest managed for amenity
value or environmental protection if specified by the country), with defined geographical boundaries.

MANAGED GRASSLAND
Grasslands on which human-induced activities are carried out, such as grazing or hay removal.

MEAN
Statistical definition: The mean, population mean, expectation or expected value is, broadly speaking, ameasure of a central value around which values sampled from a probability distribution tend to lie. The sample
mean or arithmetic average is an estimator for the mean. It is an unbiased and consistent estimator of the
population mean (expected value) and is itself a random variable with its own variance value. The sample meanis the sum of values divided by the number of values:

x =

1 n
∑ x i (xi, where i = 1,…., n are items of a sample).
n i

MEDIAN
Statistical definition: The median or population median is a value which divides the integral of a probability
density function (PDF) into two halves. For symmetric PDFs, it equals the mean. The median is the 50th
population percentile.

The sample median is an estimator of the population median. It is the value that divides an ordered sample into
two equal halves. If there are 2n + 1 observations, the median is taken as the (n + 1)th member of the orderedsample. If there are 2n, it is taken as being halfway between the nth and (n + 1)th .

METADATA
Information about data; i.e., the description of which parameters and variables are stored in a database: theirlocation, time of recording, accessibility, representativeness, owner, etc.

MODEL
Statistical definition: A model is a quantitatively-based abstraction of a real-world situation which may
simplify or neglect certain features to better focus on its more important elements.

Example: the relationship that emissions equal an emission factor times an activity level is a simple model. The
term ‘model’ is also often used in the sense of a computer software realisation of a model abstraction.

MOIST (FOREST)
Moisture regimes for boreal and temperate zones are defined by the ratio of mean annual precipitation (MAP)and potential evapotranspiration (PET): Dry (MAP/PET < 1) and Wet (MAP/PET > 1); and for tropical zones by
precipitation alone: Dry (MAP < 1,000 mm), Moist (MAP: 1,000-2,000 mm) and Wet (MAP > 2,000 mm).

MONTE CARLO METHOD
Inventory definition: The principle of Monte Carlo analysis is to perform the inventory calculation many times
by electronic computer, each time with the uncertain emission factors or model parameters and activity datachosen randomly (by the computer) within the distribution on uncertainties specified initially by the user.
Uncertainties in emission factors and/or activity data are often large and may not have normal distributions. In

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this case the conventional statistical rules for combining uncertainties become very approximate. Monte Carloanalysis can deal with this situation by generating an uncertainty distribution for the inventory estimate that is
consistent with the input uncertainty distributions on the emission factors, model parameters and activity data.

NET ANNUAL I NCREMENT
Average annual volume over the given reference period of gross increment minus natural mortality, of all trees
to a specified minimum diameter at breast height.

NET- NET ACCOUNTING
The carbon sink or source in the reporting year minus the carbon sink or source in the base year. This is theaccounting method for grazing land management, cropland management and revegetation under Article 3.4.

NORMAL DI STRIBUTION
Statistical definition: The normal (or Gaussian) distribution has the PDF given in the following equation and isdefined by two parameters (the mean µ and the standard σ deviation) .
f (x) =

1

σ 2π

−

e

( x − µ)2
2σ 2

, for - ∞ ≤ x ≤ ∞ .

OPEN FORESTS
Forests characterised by crown cover between 10 and 40% (FAO), or below the canopy cover threshold asadopted by the Party.

ORGANIC SOILS
Soils are organic if they satisfy the requirements 1 and 2, or 1 and 3 below (FAO, 1998):
1.
2.
3.

Thickness of 10 cm or more. A horizon less than 20 cm thick must have 12 percent or more organic carbon
when mixed to a depth of 20 cm;
If the soil is never saturated with water for more than a few days, and contains more than 20 percent (byweight) organic carbon (about 35 percent organic matter);If the soil is subject to water saturation episodes and has either:
At least 12 percent (by weight) organic carbon (about 20 percent organic matter) if it has no clay;(i)or
At least 18 percent (by weight) organic carbon (about 30 percent organic matter) if it has 60 percent(ii)
or more clay; or(iii)
An intermediate, proportional amount of organic carbon for intermediate amounts of clay.

OTHER LAND ( AS A LAND- USE CATEGORY)This category includes bare soil, rock, ice, and all unmanaged land areas that do not fall into any of the other fivecategories. It allows the total of identified land areas to match the national area, where data are available.

PASTURE
Grassland managed for grazing.

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PEAT SOIL (ALSO HISTOSOL)
A typical wetland soil with a high water table and an organic layer of at least 40 cm thickness (poorly drainedorganic soil).

PERCENTI LE
Statistical definition: The kth percentile or population percentile is a value which separates the lowest kth part ofthe integral of the probability density function (PDF) – i.e., an integral of a PDF tail from the kth percentile
towards lower probability densities.

PERENNIAL CROPS
Multiple year crops, includes trees and shrubs, in combination with herbaceous crops e.g., agroforestry, ororchards, vineyards and plantations such as cocoa, coffee, tea, oil palm, coconut, rubber trees, and bananas,
except where these lands meet the canopy cover threshold criteria for forest land.

POLAR/BOREAL
Mean annual temperature (MAT) is less than 0 oC.

POOL/CARBON POOL
A reservoir. A system which has the capacity to accumulate or release carbon. Examples of carbon pools areforest biomass, wood products, soils and the atmosphere. The units are mass.

POPULATIO N
Statistical definition: The population is the totality of items under consideration. In the case of a randomvariable, the probability distribution is considered to define the population of that variable.

PRACTICE
An action or set of actions that affect the land, the stocks of pools associated with it or otherwise affect theexchange of greenhouse gases with the atmosphere.

PRECISION
Inventory definition: Precision is the inverse of uncertainty in the sense that the more precise something is, theless uncertain it is.
Statistical definition: Closeness of agreement between independent results of measurements obtained understipulated conditions (see also accuracy).

PROBABILITY
Statistical definition: A probability is a real number in the scale 0 to 1 attached to a random event. There aredifferent ways in which probability can be interpreted. One interpretation considers a probability as having thenature of a relative frequency (i.e., the proportion of all outcomes corresponding to an event), whilst anotherinterpretation regards a probability as being a measure of degree of belief.

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PROBABILITY DENSITY FUNCTION
Statistical definition: A probability density function (PDF) is a mathematical function which characterizes theprobability behaviour of population. It is a function f(x) which specifies the relative likelihood of a continuous
random variable X taking a value near x, and is defined as the probability that X takes a value between x and
x+dx, divided by dx where dx is an infinitesimally small number.

PROBABILITY DISTRIBUTION
Statistical definition: A function giving the probability that a random variable takes any given value or belongs
to a given set of values. The probability on the whole set of values of the random variable equals 1.

PROPAGATION OF UNCERTAINTIESStatistical definition: The rules for propagation of uncertainties specify how to algebraically combine thequantitative measures of uncertainty associated with the input values to the mathematical formulae used ininventory compilation, so as to obtain corresponding measures of uncertainty for the output values. See Chapter
6, Quantifying Uncertainties in Practice, and Annex 1, Conceptual Basis for Uncertainty Analysis of GPG2000.

QUALITY ASSURANCE
Inventory definition: Quality Assurance (QA) activities include a planned system of review procedures
conducted by personnel not directly involved in the inventory compilation/development process to verify thatdata quality objectives were met, ensure that the inventory represents the best possible estimate of emissions andsinks given the current state of scientific knowledge and data available, and support the effectiveness of thequality control (QC) programme.

QUALITY CONTRO L
Inventory definition: Quality Control (QC) is a system of routine technical activities, to measure and control
the quality of the inventory as it is being developed. The QC system is designed to:(i)Provide routine and consistent checks to ensure data integrity, correctness, and completeness;(ii)

Identify and address errors and omissions;(iii) Document and archive inventory material and record all QC activities.
QC activities include general methods such as accuracy checks on data acquisition and calculations and the useof approved standardised procedures for emission calculations, measurements, estimating uncertainties,
archiving information and reporting. Higher tier QC activities include technical reviews of source categories,
activity and emission factor data, and methods.

RADAR DATA
Remotely-sensed data from the microwave portion of the electromagnetic spectrum, sent from and collected byaircraft or satellite after reflection from the target.

RANDOM ERRO R
See systematic and random errors.

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RANDOM VARI ABLE
Statistical definition: A variable that may take any of the values of a specified set of values and with which is
associated a probability distribution. A random variable which may take only isolated values is said to be‘discrete.’ A random variable that may take any value within a finite or infinite interval is said to be ‘continuous’.

RASTER DATA
Information stored on regular grid of points.

RASTER IMAGES
Raster data means information stored on a regular grid of points, as opposed to polygon data, which isinformation stored as the coordinates of an outline area sharing a common attribute.

REFORESTATION 9
Direct human-induced conversion of non-forested land to forested land through planting, seeding and/or thehuman-induced promotion of natural seed sources, on land that was forested but that has been converted to nonforested land. For the first commitment period, reforestation activities will be limited to reforestation occurringon those lands that did not contain forest on 31 December 1989.

RELATIVE ERROR
Maximum tolerable error which is a fraction of the value of the variable being estimated.

REMOTELY SENSED DATA
Data generally acquired by means of scanners or cameras onboard aircraft or satellites.

REMOTE SENSI NG
Practice of acquiring and using data from satellites and aerial photography to infer or measure land cover/use.
May be used in combination with ground surveys to check the accuracy of interpretation.

REMOVALS
Removals are a subset of fellings (the commercial part destined for processing). The ‘Removals’ term should
only be used in this forestry context, not as synonym for carbon sink.

REPORTING
The process of providing estimates to the UNFCCC.

RESOLUTIO N
Smallest unit of land about which land cover or use can be determined. High resolution means the resolvableland units are small.

9

In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft decision-/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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RESERVOIRS
Water bodies regulated for human activities (energy production, irrigation, navigation, recreation etc.) where
substantial changes in water area due to water level regulation occur. The term should not be used in the context
of a carbon reservoir.

REVEGETATION 10
A direct human-induced activity to increase carbon stocks on sites throught the establishment of vegetation thatcovers a minimum area of 0.05 hectares and does not meet the definitions of afforestation and reforestation
contained here.

SAMPLE
Statistical meaning: A sample is a finite set of observations drawn from a population.

SANDY SOILS
Includes all soils (regardless of taxonomic classification) having > 70% sand and < 8 % clay (based on standard
textural measurements (in FAO classification include: Arenosols, sandy Regosols)).

SEASONAL (FOREST)
Semi-deciduous forests with a distinct wet and dry season and rainfall between 1,200 and 2,000 mm per year.

SENSITIVITY
Statistical definition: A sensitivity is a measurement of how responsive one quantity is to a change in anotherrelated quantity. The sensitivity of a quantity Y that is affected by changes in another quantity X, is defined as
the change in Y divided by the change in X that caused the changes in Y.

SENSITIVITY ANALYSIS
Statistical definition: Sensitivity analysis is a study of a model algorithm to determine how sensitive (or stable) it is
to variations of its input data or underlying assumptions. It is performed by varying input values or model equations
and observing how the model output varies correspondingly. The aim of such a sensitivity analysis can include:•

Observing the range of output values corresponding to input variables lying within ‘reasonable’ ranges; and•Calculating finite difference approximations for elasticities and sensitivities as required by somemethodologies for studying error propagation within a system.

SEQUESTRATION
The process of increasing the carbon content of a carbon pool other than the atmosphere. It is preferred to use theterm “sink”.

10

In the context of the Kyoto Protocol, as stipulated by the Marrakesh Accords, cf. paragraph 1 of the Annex to draft
decision -/CMP.1 (Land use, land-use change and forestry) contained in document FCCC/CP/2001/13/Add.1, p.58.

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SETTLEMENTS
This category includes all developed land, including transportation infrastructure and human settlements of any
size, unless they are already included under other categories. This should be consistent with the selection ofnational definitions.

SIMPLE RANDOM SAMPLE
Statistical definition: A sample of n items chosen from a population such that every possible sample has thesame probability of being chosen.

SINK
Any process, activity or mechanism which removes a greenhouse gas, an aerosol, or a precursor of a greenhousegas from the atmosphere. Notation in the final stages of reporting is the negative (-) sign.

SKEWNESS
Statistical definition: Skewness is a measure of asymmetry of a PDF. It is a simple function of two moments of
the PDF, given by:

γ =

µ3

µ3

where µ2, µ3, and σ are central moments. Symmetric distributions have γ = 0. The same nameσ3
is frequently used for sample skewness, in which case both population moments are replaced by sample
moments.

µ 23 2=

SOIL ORGANIC MATTER
Includes organic carbon in mineral and organic soils (including peat) to a specified depth chosen by the country andapplied consistently through the time series. Live fine roots (of less than the suggested diameter limit for belowground biomass) are included with soil organic matter where they cannot be distinguished from it empirically.

SOURCEAny process or activity which releases a greenhouse gas, an aerosol or a precursor of a greenhouse gas into theatmosphere. Notation in the final stages of reporting is the positive (+) sign.

SPATIAL INTERPOLATIO N
Inference about the characteristics of land from known information on surrounding land locations.

SPATIALLY EXPLICIT
Mapped or otherwise geographically referenced.

SPODIC SOILS
Soils exhibiting strong podzolization (in FAO classification includes many Podzolic groups).

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STANDARD DEVIATION
Statistical definition: The population standard deviation is the positive square root of the variance. It isestimated by the sample standard deviation that is the positive square root of the sample variance.

STANDING VOLUME
Volume of standing trees, living or dead, above stump measured overbark to a predefined top diameter. Includes
all trees with diameter above a given diameter at breast height (dbh). The minimum dbh and the top diametervary by country and are usually country defined.

STATISTIC
Statistical definition: A statistic is a function of the sample random variables.

STATISTICS
Statistical definition: Statistics can refer either in a general sense to the compilation of data, frequently abouthuman activities, or in a more specific sense to the branch of science concerned with the systematic numericaltreatment of data derived from aggregates of items.

SYSTEMATIC AND RANDOM ERRO RS
Statistical definition: Systematic error is the difference between the true, but usually unknown, value of aquantity being measured, and the mean observed value as would be estimated by the sample mean of an infinite
set of observations. The random error of an individual measurement is the difference between an individual
measurement and the above limiting value of the sample mean.

SYSTEMATIC ERRO R
Statistical definition: See systematic and random errors.

TEMPERATE, COLD
Mean annual temperature (MAT) is between 0 – 10 oC.

TEMPERATE, WARM
Mean annual temperature (MAT) is between 10 – 20 oC.

TIME SERIES
Statistical definition: A time series is series of values which are affected by random processes and which areobserved at successive (usually equidistant) points in time.

TOP-DOWN MODELLING
A modelling approach which aims to infer processes and parameters at a smaller scale from measurements taken
at an aggregated scale (regional/national/continental/global).

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TRANSPARENCY
Inventory definition: Transparency means that the assumptions and methodologies used for an inventory
should be clearly explained to facilitate replication and assessment of the inventory by users of the reported
information. The transparency of inventories is fundamental to the success of the process for the communicationand consideration of information.

TREND
Inventory definition: The trend of a quantity measures its change over a time period, with a positive trend value
indicating growth in the quantity, and a negative value indicating a decrease. It is defined as the ratio of thechange in the quantity over the time period, divided by the initial value of the quantity, and is usually expressed
either as a percentage or a fraction.

TROPICAL
Mean annual temperature (MAT) is more than 20 oC.

UNCERTAINTY
Statistical definition: An uncertainty is a parameter, associated with the result of measurement thatcharacterises the dispersion of the values that could be reasonably attributed to the measured quantity (e.g., thesample variance or coefficient of variation).
Inventory definition: A general and imprecise term which refers to the lack of certainty (in inventory
components) resulting from any causal factor such as unidentified sources and sinks, lack of transparency, etc.

UNCERTAINTY ANALYSIS
Statistical definition: An uncertainty analysis of a model aims to provide quantitative measures of theuncertainty of output values caused by uncertainties in the model itself and in its input values, and to examine
the relative importance of these factors.

UNIFORM DI STRIBUTION
Statistical definition: A random variable with a uniform or rectangular distribution is confined to lie within arange over which all values are equally probable. If the upper and lower limits of the range are a and b
respectively, the PDF is a flat function from a to b (the two parameters defining the PDF).

The PDF of a uniform distribution is given by: 1

for a ≤ x ≤ bf ( x) =  b − a 0elsewhere
where
a+b
µ =
2
is the mean and(b − a) 2
12
is the variance.

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VALIDATION
Inventory definition: Validation is the establishment of sound approach and foundation. In the context ofemission inventories, validation involves checking to ensure that the inventory has been compiled correctly inline with reporting instructions and guidelines. It checks the internal consistency of the inventory. The legal use
of validation is to give an official confirmation or approval of an act or product.

VARIABILI TY
Statistical definition: This refers to observed differences attributable to true heterogeneity or diversity in a
population. Variability derives from processes which are either inherently random or whose nature and effects
are influential but unknown. Variability is not usually reducible by further measurement or study, but can becharacterised by quantities such as the sample variance.

VARIANCE
Statistical definition: The variance or population variance is a parameter of a PDF, which expresses thevariability of the population. It is the second central moment of a random variable. The sample variance isdefined as a measure of dispersion, which is the sum of the squared deviations of observations from their average,
divided by one less than the number of observations.

s2 =

1 n
2
∑ ( x i − x)n −1 i

VARIANCE OF SAMPLE MEAN
Statistical definition: The mean of a sample taken from a population is itself a random variable with its own
characteristic behaviour and its own variance. For such sample means, the appropriate estimate of the variance is
not the sample variance, which estimates the variability associated with a single simple value, but a lower value,equal to the sample variance divided by the sample size.

VERIFICATIO N
Inventory definition: Verification refers to the collection of activities and procedures that can be followed
during the planning and development, or after completion of an inventory that can help to establish its reliability
for the intended applications of that inventory.

Typically, methods external to the inventory are used to check the truth of the inventory, including comparisonswith estimates made by other bodies or with emission and uptake measurements determined from atmosphericconcentrations or concentration gradients of these gases.

WALL- TO-WALL MAPPING
Complete spatial coverage of a land area, e.g., by satellite data.

WET (FOREST)
Moisture regimes for boreal and temperate zones are defined by the ratio of mean annual precipitation (MAP)and potential evapotranspiration (PET): Dry (MAP/PET < 1) and Wet (MAP/PET > 1); and for tropical zones by
precipitation alone: Dry (MAP < 1,000 mm), Moist (MAP: 1,000-2,000 mm) and Wet (MAP > 2,000 mm).

WETLANDS
This category includes land that is covered or saturated by water for all or part of the year (e.g., peatland) andthat does not fall into the forest land, cropland, grassland or settlements categories. This category can be

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subdivided into managed and unmanaged according to national definitions. It includes reservoirs as a managed
sub-division and natural rivers and lakes as unmanaged sub-divisions.

References
Intergovernmental Panel on Climate Change (IPCC). (2000). Penman J., Kruger D., Galbally I., Hiraishi T.,
Nyenzi B., Emmanuel S., Buendia L., Hoppaus R., Martinsen T., Meijer J., Miwa K., and Tanabe K. (Eds).
Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories.
IPCC/OECD/IEA/IGES, Hayama, Japan.
Intergovernmental Panel on Climate Change (IPCC). (2000). Watson R., Noble I.R., Bolin B., Ravindranath,
N.H., Verardo D.J. and Dokken D.J. (Eds) Land use, Land-use Change, and Forestry: A Special Report.
Cambridge University Press. Cambridge, UK.
Intergovernmental Panel on Climate Change (IPCC). (2001). Houghton J. T. et al. (Eds.). Climate Change 2001:
The Scientific Basis. Contribution of Working Group I to the Third Assessment Report of theIntergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK.
FAO (1998). World Reference Base for Soil Resources. World Soil Resources Reports 84. FAO, Rome. 88 pp.
ISBN 92-5-104141-5
FAO. (2002). Proceedings of the Expert Meeting on Harmonizing Forest-related Definitions for use by various
stakeholders. FAO, Rome, Italy.
Mekkink P. (1999). Soils of Forest Reserves in the Netherlands. Report 98/35, Staring Centre, Wageningen, The
Netherlands.
UNFCCC. (2001). Paragraphs 1(a) - (e) in the Annex to draft decision -/CMP.1 (Land use land-use change andforestry), contained in document FCCC/CP/2001/13/Add.1, p.58.

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