Localizing SDG 11.6.2 via Earth Observation, Modelling Applications, and Harmonised City Definitions: Policy Implications on Addressing Air Pollution

Abstract

While Earth observation (EO) increasingly provides a multitude of solutions to address environmental issues and sustainability from the city to global scale, their operational integration into the Sustainable Development Goals (SDG) framework is still falling behind. Within this framework, SDG Indicator 11.6.2 asks countries to report the “annual mean levels of fine particulate matter (PM2.5) in cities (population-weighted)”. The official United Nations (UN) methodology entails aggregation into a single, national level value derived from regulatory air quality monitoring networks, which are non-existent or sparse in many countries. EO, including, but not limited to remote sensing, brings forth novel monitoring methods to estimate SDG Indicator 11.6.2 alongside more traditional ones, and allows for comparability and scalability in the face of varying city definitions and monitoring capacities which impact the validity and usefulness of such an indicator. Pursuing a more harmonised global approach, the H2020 SMURBS/ERA-PLANET project provides two EO-driven approaches to deliver the indicator on a more granular level across Europe. The first approach provides both city and national values for SDG Indicator 11.6.2 through exploiting the Copernicus Atmospheric Monitoring Service reanalysis data (0.1° resolution and incorporating in situ and remote sensing data) for PM2.5 values. The SDG Indicator 11.6.2 values are calculated using two objective city definitions—“functional urban area” and “urban centre”—that follow the UN sanctioned Degree of Urbanization concept, and then compared with official indicator values. In the second approach, a high-resolution city-scale chemical transport model ingests satellite-derived data and calculates SDG Indicator 11.6.2 at intra-urban scales. Both novel approaches to calculating SDG Indicator 11.6.2 using EO enable exploration of air pollution hotspots that drive the indicator as well as actual population exposure within cities, which can influence funding allocation and intervention implementation. The approaches are introduced, and their results frame a discussion around interesting policy implications, all with the aim to help move the dial beyond solely reporting on SDGs to designing the pathways to achieve the overarching targets.

A Review of Global PM2.5 Exposure Research Trends from 1992 to 2022

“…This trend has garnered global attention, leading to the formulation of Sustainable Development Goals (SDGs) with a specific target (11.6.2) for controlling PM 2.5 , which were first proposed by governments worldwide during the Rio+20 UN Conference in June 2012 [43,44]. In response, countries began to enact a series of policies to promote greener, more sustainable development after 2012 [45,46]. This worldwide mobilization has further fueled academic interest in air pollutants such as PM 2.5 .…”

Earth Observations for Sustainable Development Goals

“…Current official reporting systems, based on in-situ monitoring networks (i.e., United Nations, Eurostat), are not able to represent the actual diversity of urban conditions and are not covering smaller cities. One paper proposes to supplement official reporting with Earth Observation, to enable calculating more representative and holistic values for the indicator, based on population density, as opposed to differing city definitions [2]. Another important aspect is that Earth Observation studies, similar to this one, not only support the monitoring of the SDG indicator, but also attempt to tackle the actual problem related to the SDG targets: in this particular case, to reduce city concentrations of particulate matter and, subsequently, the exposure of citizens to harmful substances.…”

Implementation of the UN’s Sustainable Development Goals (SDGs) among the Member Cities of the “Healthy Cities Network” in Israel

“…SDG3-Ensure healthy lives and promote well-being for all at all ages-Only one city received the highest score (18) and one received 17; both are at 7-9 SEC. Almost all municipalities implement health-promotion activities, which include promoting healthy and sustainable nutrition (39 out of 45), physical activity (36), special programs for senior citizens (13), prevention of smoking (11), community gardens (10), and resilience (9).…”

“…The diversity of evaluation methods and indicators used was noted. There were studies that just researched a specific SDG [16][17][18][19]. For example, Mudau et al studied the significance of Indicator 11.3.1 in understanding the urbanization trends in cities of different sizes [16].…”