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Abstract Carbon dioxide (CO2) quantification is critical for assessing city‐level carbon emissions and sustainable urban development. While urban vegetation has the potential to provide environmental benefits, such as heat and carbon mitigation, the CO2exchange from biogenic sectors and its impact from the environmental perturbations are often overlooked. It is also challenging to simulate the plant functions in the complex urban terrain. This study presents a processed‐based modeling approach to assess the biogenic carbon fluxes from the vegetated areas over the Chicago Metropolitan Area (CMA) using the Weather Research and Forecast—Urban Biogenic Carbon exchange model. We investigate the change of CO2sink power in CMA under heatwaves and irrigation. The results indicate that the vegetation plays a significant role in the city's carbon portfolio and the landscaping management has the potential to reduce carbon emissions significantly. Furthermore, based on the competing mechanisms in the biogenic carbon balance identified in this study, we develop a novel Environmental Benefit Score metrics framework to identify the vulnerability and mitigation measures associated with nature‐based solutions (NbS) within CMA. By using the generalized portable framework and our science‐policy confluence analysis presented in this study, global cities can maximize the effectiveness of NbS and accelerate carbon neutrality.
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This content will become publicly available on January 1, 2026
City–company collaboration towards aligned science-based target setting
Abstract Cities and companies have great potential to reduce pressures on Earth system boundaries. Science-based target setting has emerged as a powerful tool to help achieve the potential, but its uptake has been limited. Moreover, cities and companies usually develop their targets separately, even though many are co-located. Focusing on the top 200 cities and 500 companies by greenhouse gas emissions, we analyse the current state and potential of adopting science-based targets for climate. Of these key actors, 110 cities with existing net-zero targets and 22 companies with existing science-based targets could together eliminate up to 3.41 GtCO2e of annual emissions. We argue that this reduction potential could increase by as much as 67% (to 5.70 GtCO2e) if the cities and companies that already have targets bring their co-located counterparts on board to keep abreast of their ambitions. Using freshwater as another example, we discuss entry points for addressing interrelated Earth system boundaries through city–company collaborations. Our findings elucidate previously untapped potentials that could accelerate transformations for operating within Earth system boundaries.
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- Award ID(s):
- 2118329
- PAR ID:
- 10637102
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- Nature Sustainability
- Volume:
- 8
- Issue:
- 1
- ISSN:
- 2398-9629
- Page Range / eLocation ID:
- 54 to 65
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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