Climate Change

1.         INDICATOR

(a)        Name:  Emissions of Greenhouse Gases (GHG).  

(b)        Brief Definition:  Anthropogenic emissions, less removal by sinks, of the greenhouse gases carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6), chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), together with the indirect greenhouse gases nitrogen oxides (NOx), carbon monoxide (CO) and non-methane volatile organic compounds (NMVOCs).  

(c)        Unit of Measurement:  Annual GHG emissions in gigagrams (Gg). Emissions of CH4, N2O, HFCs, PFCs and SF6 can be converted to CO2 equivalents using 100 year global warming potentials (GWPs) provided in the IPCC Second Assessment Report, 1995.  

(d)        Placement in the CSD Indicator Set:  Environmental/Atmosphere/Climate Change.  


(a)        Purpose:  This indicator measures the emissions of the six main GHGs which have a direct impact on climate change, less the removal of the main GHG CO2 through sequestration as a result of land-use change and forestry activities.  

(b)        Relevance to Sustainable/ Unsustainable Development (theme/sub-theme):  For about a thousand years before the industrial revolution, the amount of greenhouse gases in the atmosphere remained relatively constant. Since then, the concentration of various greenhouse gases has increased. The amount of carbon dioxide, for example, has increased by more than 30% since pre-industrial times and is currently increasing at an unprecedented rate of about 0.4% per year, mainly due to the combustion of fossil fuels and deforestation. The concentrations of methane and nitrous oxide are increasing as well due to agricultural, industrial and other activities. The concentrations of the nitrogen oxides NO and NO2 and carbon monoxide (CO) are also increasing. Although these gases themselves are not greenhouse gases, they affect atmospheric chemistry, leading to an increase in tropospheric ozone, which is a greenhouse gas. Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6) and some other halogen GHGs do not occur naturally in the atmosphere but have been introduced by human activities. They are strong greenhouse gases and have long atmospheric lifetimes. CFCs and HCFCs also deplete the stratospheric ozone layer (see ozone depleting substances).  

Since the late nineteenth century, the mean global temperature has increased by 0.4-0.8°C and the sea level has risen by 10 to 15cm. A doubling of the CO2 concentration in the atmosphere is believed to cause an increase in the global mean temperature of 1.5 to 4.5°C. To appreciate the magnitude of this temperature increase, it should be compared with the global mean temperature difference of perhaps 5 to 6°C from the middle of the last ice age to the present interglacial period.  

(c)        International Conventions and Agreements:  The United Nations Framework Convention on Climate Change entered into force in March 1994 and as of July 2000 has received 184 instruments of ratification or accession. The Convention includes a commitment by developed country Parties, including economies in transition (Annex I Parties), to aim to return emissions of CO2 and other GHGs not controlled by the Montreal Protocol to their 1990 levels by 2000. The Kyoto Protocol was adopted in December 1997 and has received 84 signatures.  It will enter into force after it has been ratified by at least 55 Parties to the Convention, including developed countries accounting for at least 55 per cent of the total 1990 CO2 emissions from this group.  Meanwhile countries are to continue to carry out their commitments under the Convention.  

Ozone-depleting greenhouse gases (such as CFCs and HCFCs) are controlled by the Vienna Convention and the Montreal Protocol (see ozone depleting substances).  

(d)        International Targets/Recommended Standards:  The Kyoto Protocol sets targets for each of the developed country Parties and economy in transition Parties with a view to reducing their overall emissions of the six main GHGs by at least 5 per cent below 1990 levels in the commitment period 2008 to 2012.  

(e)        Linkages to Other Indicators:  This indicator is linked to many other socio-economic and environmental indicators, including GDP growth rate, energy consumption, environmental protection expenditures, and expenditures on air pollution abatement.  


(a)        Underlying Definitions and Concepts:  Greenhouse gases contribute in varying degrees to global warming depending on their heat absorptive capacity and their lifetime in the atmosphere. The global warming potential (GWP) describes the cumulative effect of a gas over a time horizon (usually 100 years) compared to that of CO2. For example, the global warming potential of CH4 (methane) is 21, meaning that the global warming impact of one kg of CH4 is 21 times higher than that of one kg of CO2.  The global warming potentials of ozone-depleting greenhouse gases (such as CFCs and HCFCs) are highly uncertain, since they depend on the depletion of ozone, itself a greenhouse gas. No global warming potentials are provided for indirect greenhouse gases.  

(b)        Measurement Methods:  In some cases, GHG emissions can be measured directly at the source.  More commonly, emissions are estimated from data on emission sources, for example oil sales data or cattle numbers, using an emission factor for each source.  

(c)        Limitations of the Indicator:  This indicator shows the net amount of GHGs entering the atmosphere for each reporting country each year.  It does not show how much the climate will be affected by the increased accumulation of GHGs or the consequent effect of climate change on countries.  Data is available and reported mainly for developed countries and economies in transition.  

(d)        Status of the Methodology:  Developed country Parties to the Convention have been reporting GHG data beginning with 1990 data since 1994.  The IPCC has published two sets of guidelines on methodologies for the estimation of GHG inventories and further elaborated this with guidance on good practice in 2000.  

(e)        Alternative Definitions/Indicators:  GHG emissions can alternatively be measured on a gross instead of net basis in which case no account is taken of removal by sinks.  There are a number of other gases that indirectly produce GHGs and these could also be included in the scope of the definition.  The GWP potential can be calculated over different time horizons, such as 20 years or 500 years.  


(a)        Data Needed to Compile the Indicator:  Greenhouse gas emissions data.  

(b)        National and International Data Availability and Sources:  National communications from Parties to the Convention, including both developed and developing countries, are available. Developing countries report on a limited basis. At the international level, the UNFCCC Secretariat database has information based on annual data inventory submissions from developed and economy in transition countries.  

(c)        Data References:  Not Available.  


(a)        Lead Agency:  The lead agency is the Secretariat of the United Nations Framework Convention on Climate Change (UNFCCC).  The contact point is the Executive Secretary, Secretariat, UNFCCC, fax no. (41 22) 970 9034.  

(b)        Other Contributing Organizations:  Intergovernmental Panel on Climate Change (IPCC).  

6.         REFERENCES 

(a)        Readings:   

First review of information communicated by each Party included in Annex I to the     Convention. UN document A/AC.237/81 and corr. 1.  

UNFCCC in‑depth review reports on individual countries.  

(b)        Internet sites:   

www.unfccc.int  (UNFCCC)  

www.ipcc.ch  (IPCC)  

www.ipcc.nggip.iges.or.jp  (IPCC technical support)  




Ozone Layer Depletion

 1.         INDICATOR 

(a)        Name:  Consumption of Ozone Depleting Substances (ODS). 

(b)        Brief Definition:  This indicator will show the amounts of Ozone Depleting Substances being eliminated as a result of the Montreal Protocol. 

(c)        Unit of Measurement:  Tonnes of ODS weighted by their Ozone Depletion Potential (ODP). 

(d)        Placement in the CSD Indicator Set:  Environmental/Atmosphere/Ozone layer depletion. 


(a)        Purpose:  This indicator signifies the commitment to phase out the ODS of the countries which have ratified the Montreal Protocol on Substances that Deplete the Ozone Layer and its Amendments of London (1990), Copenhagen (1992), Montreal (1997) and Beijing (1999). 

(b)        Relevance to Sustainable/Unsustainable Development (theme/sub-theme): The phaseout of ODS, and their substitution by less harmful substances or new processes, will lead to the recovery of the ozone layer.  Stratospheric ozone absorbs most of the biologically damaging ultraviolet radiation (UV-B).  Without the filtering action of the ozone layer more UV-B radiation can penetrate the atmosphere to have adverse effects on human health, animals, plants, micro-organisms, marine life, materials, biogeochemical cycles, and air quality. 

(c)        International Conventions and Agreements:  The Vienna Convention for the Protection of the Ozone Layer and its Montreal Protocol on Substances that Deplete the Ozone Layer and the London, Copenhagen, Montreal and Beijing Amendments to the Protocol. 

(d)        International Targets/Recommended Standards:  The international target under the agreements listed in 2 (c) is the complete phase out of ODS. 

(e)        Linkages to Other Indicators:  This indicator has links to other environmental and institutional indicators, such as number of chemicals banned or restricted and ratification of international agreements.  It has significant implications to human health and natural resources. 


(a)                Underlying Definitions and Concepts:  Ozone Depleting Substance (ODS) means any organic substance containing chlorine or bromine, which destroys the stratospheric ozone layer.  Controlled substance means a substance in Annex A, Annex B, Annex C or Annex E of the Montreal Protocol, whether existing alone or in a mixture.  It includes the isomers of any such substance, except as specified in the relevant Annex, but excludes any controlled substance or mixture which is in a manufactured product other than a container used for the transportation or storage of that substance.  Production means the amount of listed, controlled substances produced, minus the amount destroyed by technologies to be approved by the Parties to the Montreal Protocol and minus the amount entirely used as feedstock in the manufacture of other chemicals.  The amount recycled and reused is not to be considered as "production".  Consumption is the sum of production plus imports minus exports of controlled substances.  We are addressing apparent consumption.  Weighted tonnes of ODS means the amount of ODS multiplied by their ozone depleting potential.  Ozone depleting potential (ODP) is a relative index of the ability of a substance to cause ozone depletion.  The reference level of 1 is assigned as an index to CFC-11 and CFC-12.  If a product has an ODP of 0.5, a given weight of the product in the atmosphere would, in time, deplete half the ozone that the same weight of CFC-11 or CFC-12 would deplete.  ODPs are calculated from mathematical models which take into account factors such as the stability of the product, the rate of diffusion, the quantity of depleting atoms per molecule, and the effect of ultraviolet light and other radiation on the molecules. 

(b)        Measurement Methods:  Weighted Tonnes of ODS for production are the sum of national annual production (in tonnes) of each controlled substance (as reported to the Ozone Secretariat in accordance with Article 7 of the Montreal Protocol) multiplied by the ozone depleting potential of that substance (as listed in Annexes A, B, C and E of the Handbook for the International Treaties for the Protection of the Ozone Layer, 2000).  It can be found at: http://www.unep.org/ozone or http://www.unep.ch/ozone.  Weighted Tonnes of Ozone Depleting Substances for consumption are obtained through a similar calculation using national annual consumption values (in tonnes). 

(c)        Limitations of the Indicator:  Availability and accuracy of data and timely reporting will determine the country's ability to use the indicator.  The indicator by itself does not reveal much about current trends in the deterioration of the ozone layer because of delays in ecosystem response. 

(d)        Status of the Methodology:  For more information, please consult the Reports of the Secretariat on information provided by the Parties in accordance with Article 7 of the Montreal Protocol or the Home Page at: http://www.unep.org/ozone or http://www.unep.ch/ozone

(e)        Alternative Definitions/Indicators:  An alternative indicator could focus on the phase out of ODS. 


(a)        Data Needed to Compile the Indicator:  Data on production, imports and exports of controlled substances by the Parties to the Montreal Protocol. 

(b)        National and International Data Availability and Sources:  The data are available for most countries, on a national level, on a regular annual basis, as part of their reporting obligations to the Montreal Protocol.  At the international level from the Ozone Secretariat in Nairobi and from the Multilateral Fund Secretariat in Montreal.  The data sources are the Ozone Secretariat and the national government ministry responsible for reporting to the Montreal Protocol. 

(c)        Data References:  UNEP, Report of the Secretariat on Information Provided by the Parties in Accordance with Article 7 and 9 of the Montreal Protocol, United Nations Environment Programme, pp. 105, 1999. UNEP, Production and Consumption of Ozone Depleting Substances, 1986-1998, United Nations Environment Programme, pp. 41, 1999. Web site: http://www.unep.org/ozone or http://www.unep.ch/ozone


(a)        Lead Agency:  The lead agency is the United Nations Environment Programme (UNEP)/Ozone Secretariat.  The contact point is the Executive Secretary of the Ozone Secretariat, fax no. (254-2) 62-3601/62-3913. 

(b)        Other Contributing Organizations:  Other organizations interested in the further development of this indicator would include: The Multilateral Fund Secretariat, the Global Environment Facility (GEF) Secretariat, United Nations Development Programme (UNDP), UNEP Division of Technology, Industry & Economics (UNEP DTIE), United Nations Industrial and Development Organization (UNIDO), the World Bank, the Technology and Economic Assessment Panel to the Montreal Protocol, the Parties to the Montreal Protocol, the Organisation for Economic Co-operation and Development (OECD), and members associated with the Alternative Fluorocarbon Environmental Acceptability Study (AFEAS). 

6.         REFERENCES 

(a)        Readings:  

Ozone Secretariat, UNEP, Handbook for the International Treaties for the Protection of the Ozone Layer, pp.367, 2000. (ISBN: 92- 807-1867-3). 

UNEP, Synthesis of the Reports of the Scientific, Environmental Effects and Technology and Economic Assessment Panels of the Montreal Protocol.  A Decade of Assessments for Decision Makers Regarding the Protection of the Ozone Layer: 1989-1998, United Nations Environment Programme, pp. 161, 1999. (ISBN: 92-807- 1733-2). 

UNEP, Reports of the Technology and Economic Assessment Panel of the Montreal Protocol. 

Reporting of Data by the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer. 

(b)        Internet sites:  













Air Quality

1.         INDICATOR  

(a)        Name:  Ambient concentration of air pollutants in urban areas.  

(b)        Brief Definition:  Ambient air pollution concentrations of ozone, carbon monoxide, particulate matter  (PM10, PM2,5, SPM, black smoke), sulphur dioxide, nitrogen dioxide, nitrogen monoxide, volatile organic compounds including benzene (VOCs) and lead.  

(c)        Unit of Measurement:  μg/m3, ppm or ppb, as appropriate; or percentage of days when standards/guideline values are exceeded.  

(d)              Placement in the CSD Indicator Set:  Environmental/Atmosphere/Air Quality.  

2.                 POLICY RELEVANCE  

(a)        Purpose:  The indicator provides a measure of the state of the environment in terms of air quality and is an indirect measure of population exposure to air pollution of health concern in urban areas.  

(b)        Relevance to Sustainable/Unsustainable Development (theme/sub-theme):  An increasing percentage of the world's population lives in urban areas.  High population density and the concentration of industry exert great pressures on local environments.  Air pollution, from households, industry power stations and transportation (motor vehicles), is often a major problem.  As a result, the greatest potential for human exposure to ambient air pollution and subsequent health problems occurs in urban areas.  Improving air quality is a significant aspect of promoting sustainable human settlements.  

The indicator may be used to monitor trends in air pollution as a basis for prioritising policy actions; to map levels of air pollution in order to identify hotspots or areas in need of special attention; to help assess the number of people exposed to excess levels of air pollution; to monitor levels of compliance with air quality standards; to assess the effects of air quality policies; and to help investigate associations between air pollution and health effects.  

(c)              International Conventions and Agreements:  None.  

(d)             International Targets/Recommended Standards:  World Health Organization (WHO) air quality guidelines exist for all the pollutants of this indicator, except nitrogen monoxide.  Many countries have established their own air quality standards for many of these pollutants.  

(e)              Linkages to Other Indicators:  This indicator is closely linked to others which relate to causes, effects, and societal responses.  These include, for example, the indicators on population growth rate, rate of growth of urban population, percent of population in urban areas, annual energy consumption per capita, emissions of sulphur oxides and nitrogen oxides, life expectancy at birth, total national health care as a percent of Gross National Product, share of consumption of renewable energy resources, environmental protection expenditures as a percent of Gross Domestic Product, expenditure on air pollution abatement, childhood morbidity due to acute respiratory illness, childhood mortality due to acute respiratory illness, capability for air quality management, and availability of lead-free gasoline.  


(a)      Underlying Definitions and Concepts:  The indicator may be designed and constructed in a number of ways.  Where monitored data are available, it is usefully expressed in terms of mean annual or percentile concentrations of air pollutants with known health effects – e.g., ozone, carbon monoxide, particulate matter (PM10, PM2,5, SPM), black smoke, sulphur dioxide, nitrogen dioxide, volatile organic compounds including benzene (VOCs) and lead – in the outdoor air in urban areas.  Alternatively, the indicator might be expressed in terms of the number of days on which air quality guidelines or standards are exceeded (though in this, comparisons need to be made with care because of possible changes or differences in guideline values).  

Where monitoring data are unavailable, estimates of pollution levels may be made using air pollution models.  Dispersion models, however, depend on the availability of emission data; where these are not available, surveys may be conducted using rapid source inventory techniques.  Because of the potential errors in the models or in the input data, results from dispersion models should ideally be validated against monitored data.  

(b)        Measurement Methods:  Suitable air monitors must fulfil several requirements, such as detection limits, interferences, time resolution, easy operation and of course, cost.  There are several good references in the literature or available at agencies on air monitoring and analysis from where information can be obtained.  It is important, however, to refer to the published scientific literature for the most appropriate and recent air monitoring methods.  

A number of models are available for estimation of ambient concentration of air pollutants.  Most of them are founded on the Gaussian air dispersion model.  

(c)        Limitations of the Indicator:  Measurement limitations relate to detection limits, interferences, time resolution, easy operation, and cost.  Evaluation of the accuracy of model results is critical before relying on model output for decision-making.  

(d)        Status of the Methodology:  The methodology is widely used in many developed and developing countries.  

(e)        Alternative Definitions:  None.  

4.                   ASSESSMENT OF DATA  

(a)        Data Needed to Compile the Indicator:  Data must be time and spatially representative concentrations such as, for example, mean annual concentrations (mean concentrations of the pollutant of concern, averaged over all hours of the year) or percentile concentration (concentration of the pollutant of concern exceeded in 100-X% of hours, where X is the percentile as defined by the relevant standards).  In addition, information must be available on site location and type (e.g., industrial or residential area).  

(b)        National and International Data Availability and Sources:  Data on ambient air pollution concentrations is often routinely collected by national or local monitoring networks.  Data is often also collected for research purposes by universities and research institutes.  In addition, industry collects many data.              

(c)             Data References:  Data on ambient air pollution can be obtained from national and local monitoring networks.  Sometimes, data is available from universities, research institutes and industry.  In addition, a growing volume of data can be obtained from international sources such as the WHO Healthy Cities Air Management Information System (AMIS) of the European Environmental Agency.  



(a)                Lead Agency:  The lead agency is the World Health Organization (WHO).  The contact point is the Director, Department for the Protection of the Human Environment; fax no. (41 22) 791 4159. 

(b)               Other Contributing Organizations:  The United Nations Environment Programme.  

6.                  REFERENCES  

(a)               Readings:  

WHO (2000 in print) Air Quality Guidelines for Europe (revision of Air Quality Guidelines for Europe 1987).  WHO Regional Office for Europe, Bilthoven Division.  

WHO (2000 in print) Human Exposure Assessment, Environmental Health Criteria Document 214, Programme of Chemical Safety.  

WHO (2000)  Decision-Making in Environmental Health: From Evidence to Action, edited by C. Corvalan, D. Briggs and G. Zielhuis, E & FN Spon, London, New York.  

WHO (1999) Monitoring Ambient Air Quality for Health Impact Assessment, WHO Regional Publications, European Series, No. 85.  

WHO (1999) Environmental Health Indicators:  Framework and Methodologies.  Prepared by D. Briggs, Occupational and Environmental Health.  

WHO (1999) Global Air Quality Guidelines: Occupational and Environmental Health  (available on the web only).  

WHO (1987) Air Quality Guidelines for Europe, WHO Regional Office for Europe, Bilthoven Division.  

Schwela & Zali (eds. 1999) Urban Traffic Pollution.  Edited by D. Schwela and O. Zali, E & FN Spon, London, New York.  

UNEP/WHO (1992) Urban Air Pollution in Megacities of the World, Blackwell Publishers, Oxford, UK.  

UNEP/WHO (1994) Global Environmental Monitoring System (GEMS/Air), Methodology Review Handbook Series. Volumes 2, 3, and 4.  

(b)                Internet sites:  







1.         INDICATOR  

(a)        Name:  Arable and Permanent Crop Land Area. 

(b)        Brief Definition:  Arable and permanent crop land is the total of “arable land” and “land under permanent crops”.  Arable land is the land under temporary crops, temporary meadows for mowing or pasture, land under market and kitchen gardens and land temporarily fallow (for less than five years); and land under permanent crops is the land cultivated with crops that occupy the land for long periods and need not be replanted after each harvest. 

(c)        Unit of Measurement:  1000 ha. 

(d)        Placement in the CSD Indicator Set:  Environmental/Land/Agriculture. 


(a)        Purpose:  This indicator shows the amount of land available for agricultural production and, inter alia, the cropland area available for food production.  The data when related to other variables such as population, total land area, gross cropped area, fertilizer use, pesticides use, etc., can also be used to study agricultural practices of the country. In order to be useful, it must be available as a time series. 

(b)        Relevance to Sustainable/Unsustainable Development (theme/sub-theme): Population growth in developing countries is driving a rapid increase in the demand for food and fibre.  At the same time, rising population density in rural areas diminishes the farm size.  Small farmers are forced to extend cultivation to new areas, which are fragile and not suitable for cultivation.  Crop intensification, which has contributed significantly to agricultural growth in recent years, can ease the pressure on cultivating new lands but farm practices adopted for raising yields can also, in some situations, result in damaging the environment (such as when expanding into new areas).  Changes in the indicator value over time or between various components may show increased or decreased pressure on agricultural land. This indicator is of value to land planning decision making. 

(c)        International Conventions and Agreements:  Not available. 

(d)        International Targets/Recommended Standards:  Not applicable. 

(e)        Linkage to Other Indicators:  The indicator is primarily linked to other measures related to land resources covered in the Chapter 10: “Integrated Approach to the Planning and Management of Land Resources” and Chapter 14: “Promoting Sustainable Agriculture and Rural Development” of the Agenda 21.  This includes indicators such as land use changes, share of irrigated area in the arable and permanent crop land area, per capita arable and permanent crop land area, etc. 


(a)        Underlying Definitions and Concepts:  The concept of arable land and land under permanent crop is clearly defined. Arable land is the land under temporary crops (double-cropped areas are counted only once), temporary meadows for mowing or pasture, land under market and kitchen gardens and land temporarily fallow (less than five years).  The abandoned land resulting from shifting cultivation is not included in this category.  Data for arable land are not meant to indicate the amount of land that is potentially cultivable.  Similarly land under permanent crops is the land cultivated with crops that occupy the land for long periods and need not be replanted after each harvest, such as cocoa, coffee and rubber; this category includes land under flowering shrubs, fruit trees, nut trees and vines, but excludes land under trees grown for wood or timber. 

(b)        Measurement Methods:  The indicator is connected to the use of land for agricultural activity and is historically based on point estimates derived from data collected in periodic agricultural censuses and surveys.  

(c)        Limitations of the Indicator:  This indicator does not reveal anything about increased productivity of agricultural land, or of the spatial variation in land quality. 

(d)        Status of the Methodology:  Concepts and methods of measurements for the indicator are well defined and documented.  However, some of the countries follow somewhat different concepts.  For example, some countries take arable land as the land that is potentially cultivable, whereas the actual definition excludes permanent fallow land and land under permanent meadows and pastures.  Similarly, “permanent” status for pastures, etc., is taken as ten years by some countries instead of the period of five years recommended by the Food and Agriculture Organization of the United Nations (FAO).  

(e)        Alternative Definitions/Indicators:  Agricultural land that includes permanent pastures and meadows is a more appropriate indicator which could universally be related to data on use of fertilizers, pesticides and statistics on irrigated area (as some countries have permanently cultivated pastures). 


(a)        Data Needed to Compile the Indicator:  Data on arable land and land under permanent crops.  Data on permanent pastures and fallow land also would be useful for undertaking quality check. 

(b)        National and