Abstract
Urban regions, which "inhale" O2from the air and "exhale" CO2and atmospheric pollutants, including harmful gases and fine particles, are the largest sinks of atmospheric O2, yet long-term O2measurements in urban regions are currently lacking. In this study, we report continuous measurements of atmospheric O2in downtown Lanzhou, an industrial metropolis in northwestern China. We found declines in atmospheric O2associated with deteriorated air quality and robust anticorrelations between O2and gaseous oxides. By combining O2and pollutants measurements with a Lagrangian atmospheric transport model, we quantitatively break down "urban respiration" (ΔO2URB) into human respiration (ΔO2RES) and fossil fuel combustion (ΔO2FF). We found increased ΔO2FFcontribution (from 66.92% to 72.50%) and decreased ΔO2REScontribution (from 33.08 to 27.50%) as O2declines and pollutants accumulate. Further attribution of ΔO2FFreveals intracity transport of atmospheric pollutants from industrial sectors and suggests transportation sectors as the major O2sink in downtown Lanzhou. The varying relationships between O2and pollutants under different conditions unfold the dynamics of urban respiration and provide insights into the O2and energy consumption, pollutant emission, and intracity atmospheric transport processes.
Original language | English |
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Pages (from-to) | 2286-2296 |
Number of pages | 11 |
Journal | Environmental Science and Technology |
Volume | 57 |
Issue number | 6 |
DOIs | |
Publication status | Published - 14 Feb 2023 |
Externally published | Yes |
Keywords
- air pollution
- anthropogenic impact
- urban habitability
- urban Omeasurements
- vehicle pollutants