Environmental justice in a very green city: Spatial inequality in exposure tourban nature, air pollution and heat in Oslo, Norway br

Poorer citizens are often more exposed to environmental hazards due to spatial inequalities in the distribution of urbanblue-green space. Few cities have managed to prevent spatial and social inequality despite sustainable developmentstrategies like compact city planning. We explore whether environmental injustice exists in a city where one wouldleast expect tofind it: a city with abundant nature, an affluent population governed by a left leaning social democraticcity council, andan aggressive densification strategy;Oslo, Norway.Green spacewas measured with a satellite-derivedvegetation index which captures the combined availability of gardens, street trees, parks and forest. Blue space wasdefined by the proximity of residential areas to the closest lake, river or fjord. We found that poorer city districts,often with greater immigrant populations, have less available blue-green spaces and are disproportionately exposedto hazardous air pollution levels, but not extreme heat compared to wealthier city districts. Citizens living within100 m of a water body are likely to earn US$ 20,000 more per year than citizens living 500 m away from water,and a US$ 3000 increase in annual income corresponds to a 10 % increase in green space availability. Hazardousair pollution concentrations in the poorest city districts were above levels recommended by the WHO and Oslo munic-ipality. Historical trends showed that districts undergoing population densification coincide with the lowest availabil-ity of blue-green space, suggesting that environmental justice has been overlooked in compact city planning policy.Despite Oslo's affluence and egalitarian ideals, the patterns of inequality we observed mirror the city's historicaleast-west class divide and point to spatial concentration of wealth as a core factor to consider in studies of green seg-regation. Urban greening initiatives in Oslo and other cities should not take spatial equality for granted, and insteadconsider socio-economic geographies in their planning process