What are SDG Indicators?

The United Nations (UN) is currently implementing the 2030 Agenda for Sustainable Development, which was adopted by all UN Member States in 2015 and includes 17 Sustainable Development Goals (SDGs) at its core, which seek to define and manage progress towards sustainable development through social inclusion, economic growth and environmental sustainability. The 17 SDGs are further defined into 169 related targets that are measured with 232 Indicators. The SDG indicators represent the means by which national governments can monitor achievement on and report progress toward the SDG targets. Each SDG indicator has one Custodian Agency mandated to compile monitoring guidelines for measuring and reporting on the indicator and to support national governments to set and report on national priorities and targets. Each indicator is classified by tier, based on the level of methodological development and overall data availability.

What is SDG 11.6.2?

SMURBS focuses on Indicator 11.6.2 of SDG goal 11, which aims to "make cities and human settlements inclusive, safe, resilient and sustainable." Indicator 11.6.2 refers to the "Annual mean levels of fine particular matter (e.g. PM_2.5 and PM₁₀) in cities (population weighted)" and works towards SDG target 11.6: "by 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management." Indicator 11.6.2 is a tier 1 indicator, i.e. it has a conceptually clear, established methodology, standards available and data is regularly produced by countries, and the custodian agency is the World Health Organization (WHO).

What is particulate matter (PM)?

Particulate matter (PM) is an agreed upon indicator of air pollution (although there are many pollutants dictating air quality). Fine particles, i.e. PM_2.5, particles with a diameter of 2.5 microns or less, are able to penetrate deeply into the respiratory tract and shown to pose a major risk to health and increase the risk of morbidity and mortality [WHO]. In the urban setting, air pollution is a point of great concern as it relates to human health and presents city-specific complexities and can result in disproportionate impacts to subgroups of the city's population. In Europe, although the air quality in many cities has improved over time, many urban areas still experience unsatisfactory air quality levels.

How does the UN measure Indicator 11.6.2?

The UN official approach for reporting on this indicator is to have the country's national statistical offices or responsible agency (e.g. Ministries of Health or Environment) report a population weighted mean for the country, using the following algorithm:

C_n represents the estimated national annual mean concentration of PM_2.5 (measured in micrograms per cubic meter, μg/m³) of a specific sub-region, n, of the country, and P_n is the population of that region [UNSD].

What is SMURBS?

SMart URBan Solutions for air quality, disasters and city growth (SMURBS) is a project which integrates Earth Observation (EO) expertise to promote the 'smart city' concept and enhance urban resilience to specific urban pressures. SMURBS has received funding from the European Union's Horizon 2020 Research and Innovation Programme, as the winning project of ERA-PLANET's transnational call under Strand 1 "Smart Cities and Resilient Societies", and will be implemented between September 2017 and August 2020. For more information, please visit the website.

SMURBS focuses on Indicator 11.6.2 of SDG goal 11, which aims to "make cities and human settlements inclusive, safe, resilient and sustainable." Indicator 11.6.2 refers to the "Annual mean levels of fine particular matter (e.g. PM_2.5 and PM₁₀) in cities (population weighted)" and works towards SDG target 11.6: "by 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management." Indicator 11.6.2 is a tier 1 indicator, i.e. it has a conceptually clear, established methodology, standards available and data is regularly produced by countries, and the custodian agency is the World Health Organization (WHO).

How is the indicator calculated?

SMURBS adopts the Functional Urban Area (FUA) concept [OECD & EC] that is followed by the CLMS, where FUA is the urban centre (at least 50,000 inhabitants) and its commuting zone. SMURBS is purposefully providing this FUA-specific data visualization and city-view tool (as opposed to evaluating the entire geographic area/country) to enable targeted mitigation measures to lower the concentration, population exposure and actual SDG indicator (towards Target 11.6).

One of SMURBS overarching goals is to address the SDG framework and specifically Goal 11. Moreover, it brings Earth Observation expertise (including satellites, in situ and models) and combines it with Smart City methods to create solutions for various urban pressures such as air pollution. Copernicus Services on the other hand, provide a unique source of completely free and open high quality data. Thus SMURBS, acknowledging the fact that most people live in cities and it is there where real opportunities lie to confront air pollution, utilizes two of Copernicus Services' (Copernicus Atmospheric Monitoring Service-CAMS and Copernicus Land Monitoring Service-CLMS) products and creates an elegant tool to provide a directly comparable product to the official UN indicator. However, the platform provides this information on a yearly basisand, perhaps more importantly, spatially disaggregated over each country (as opposed to a single value), thus enabling the identification of the city-drivers of the national air quality conditions

When the viewer first looks at the platform, there are many ways to start visualizing and breaking down the data, starting from the European viewpoint, down to the country and eventually at the FUA level. In the bottom left, each country in Europe is denoted along with their annual averages of PM_2.5 for 2014-2018 allowing for a country-to-country comparison. The year-slider in the map view can navigate the user through the five available years (2017 and 2018 are interim data as opposed to the validated data of the previous years). On the top-left is a search bar, where the user can search for a specific country or FUA. Below the search bar is a table containing all the FUAs of the app listed alongside their related country, population etc.

The user can choose a country through the map view, and once a country is selected, an informational box will pop-up showing the name of the country along with the total annual PM_2.5 concentrations, population-weighted (for the years 2014-2018). The table focuses on this country. FUAs of this country and for the rest of Europe also appear on the map. The user can add FUAs in the graph chart at the bottom left by ticking FUAs in the table. The country's value of the SDG indicator is hidden by default and can be un-hidden by pressing on the strikethrough names, as is the Europe Annual value (where Europe is treated as one single country). The user can also add FUAs from other countries in the same graph, either by finding them in the table or in the map view.

The solid black line on this graph indicates the WHO Air Quality Guideline Value of 10 μg/m3 annual mean, as WHO is the custodian agency for SDG indicator 11.6.2 and the UN’s authoritative health body, while the dashed black line indicates the EU’s limit value for PM_2.5 of 25 μg/m³.

As PM is acknowledged to be an important public health issue the WHO maintains Air Quality Guideline Values. This value for PM_2.5 is an annual mean concentration of 10 μg/m³. Likewise, European Commission (EC) air quality directives provide legislation limiting the annual pollutant concentration threshold in zones and agglomerations throughout the European Union. The PM_2.5 Air Quality Standard for Europe is a legally binding limit value of 25 μg/m³ annual average. The EC has additional PM_2.5 objectives in Directive 2008/50/EC, targeting exposure of the population through a PM_2.5 Exposure concentration obligation of 20 μg/m³ based on the 3-year average (legally binding in 2015) and a PM_2.5 Exposure reduction target of 18 μg/m³, which is to be attained where possible in 2020 and is based on the value of the exposure indicator in 2010 (also based on a 3-year average).

Years 2017 and 2018 currently contain "interim" and not "validated" data from the CAMS catalogue (Regional Ensemble Reanalysis). Moreover, the spatial resolution of the product is approximately 11x11km.