Research articles

Focusing on the carbon storage potential of urban vegetation, soils and buildings, this Article assesses the literature on carbon dioxide removal at the urban scale. With the prospect of making cities into carbon sinks, the authors identify research gaps and recommendations related to governance, economic barriers and implementation.

This study compares the links between nature and health and well-being experienced by individuals living in different contexts in three cities in the metropolitan area of Asunción, Paraguay. It found that, for people living in informal settlements, proximate nature can have negative impacts on life satisfaction. However, a strong connection to nature may lead to better mental health and higher life satisfaction, as experienced by people living in formal settlements and the evidence from the Global North.

This study looks at Jiang Han Road in Wuhan, one of the most influential shopping streets in the city center, and examines the impacts of digitalization in the post-COVID era. It found a shift in the economic activity towards socialization in the digital space, and revealed key socioeconomic-spatial patterns fostering the adaptive capacity of the street.

Using data from cities in China between 2000 and 2019, this study examined the influence of strategic interactions between mayors on carbon intensity. It found a relationship between carbon reduction in neighboring cities and the level of reduction in the reference city, in addition to an ‘imitation competition’ between cities to either reduce or increase emissions.

This study designs a new model based on medium-resolution satellite imagery to assess building damage from war, using the cases of Syria and Ukraine. It found that building damage has broader consequences for the population affected, especially when accounting for hospitals and schools.

This study assesses the effects of working-from-home on vehicle miles traveled and transit ridership during the pandemic and finds a direct and negative relationship between them: a 1% decrease in onsite workers corresponds to a 0.99% decrease in vehicle miles traveled and a 2.26% decrease in transit ridership.

Forests hold and absorb carbon, addressing a root cause of climate change. Given the rise of cities, many current and potential forests surround cities in ‘peri-urban’ areas. These peri-urban forests may play a particularly important role in providing ecosystem services and promoting livable cities. This study geographically assesses peri-urban areas available worldwide for planting trees under different scenarios, finding enormous capacity.

This study looks at the changes in Chinese port cities in relation to demography and emissions reductions to examine the relationship between health and emissions. They found that even though shipping-related PM_2.5 decreased, mortality associated with long-term exposure to it increased by 11%.

This study analyzed data on 793 cities to see how the COVID-19 pandemic affected their climate commitment and actions. It found that although climate actions persist, funding has fallen and less than half of the cities implemented green recovery initiatives.

This study compares urban activities by frequency and matches them with socioeconomic data in three US cities. It found that mobility patterns predict economic outputs but it is the infrequent activities (for example, going to French restaurants) that have the highest explanatory power.

Adapting to warming cities is increasingly crucial. This study determines the most effective retro-reflective surfaces, which reflect incoming solar radiation. The authors consider various latitudes, seasons, urban geometries, street orientations and wall directions to assess the broad applicability of this cooling strategy.

Flood risk exposure has traditionally focused on people’s place of residence, but people do not spend all day in their homes. This Article depicts a more complex story by place and time of day, arguing that flood risk exposure is more complex than what traditional measures show.

Gun ownership and gun violence are both prevalent in the United States. Using urban scaling theory, this study finds proportionately more firearm violence in larger US cities and gun access and ownership in smaller cities. Exploring deviations from the scaling laws informs our understanding of the role of self-protection.

This study tracked, using remote sensing, the land used for homesteading in Wuhan, China. It found that about 5% of the total land in the city is used for this purpose and that homesteads are more likely to appear on land that has been urbanized recently.

This study examines the influence of greenspace and air pollution on allostatic load, a measure of stress, in the United Kingdom. It found that people living in areas with more air pollutants were more likely to have a higher allostatic load, whereas greenness was associated with a lower allostatic load.

As climate warms, understanding the potential of green roofs to mitigate urban overheating and related energy consumption is increasingly important. Considering Seoul, this study finds that green-roof design should consider local meteorology and that adding them across the city could reduce energy use intensity by almost 8%.

This paper investigates changes in racial residential segregation in US cities between 1990 and 2020 with a flexible decomposition method. It finds that almost all decreases in segregation were produced by the movement of Black, Hispanic and Asian people while changes in the distribution of the white population were mostly associated with increasing segregation. Hence, segregation has decreased despite the majority group’s efforts to resegregate themselves.

Urban agriculture is intuitively appealing, but its carbon footprint is unclear. This analysis of case studies in the United States and northern Europe finds that food from urban agriculture is much more carbon-intensive but that circularity, such as by recycling of food waste, on long-used city plots can help urban agriculture outperform conventional agriculture.

COVID reshaped our use of urban space, including parks and other green space. This systematic review finds that green space use increased in wealthier regions and in more-exclusive green areas, such as private gardens, among and within countries, yet decreased in less wealthy regions and in spaces open to all.

Waste production is a basic output of human society, and its scale and logistics challenge cities and our Earth system. This study identifies universal patterns by which wastewater, municipal solid waste, and greenhouse gas waste scale across urban systems worldwide.