Integrated modeling and quantitative analysis of N2O emission before and after COVID-19: A case in Guangdong Province

• A N 2 O emission model considering the age of vehicles and fuel efficiency is proposed. • A bottom-up N 2 O emission inventory for all sectors in Guangdong has been constructed. • Mobile source combustion is the largest contributor to energy utilization emission. • Power generation drop caused by labor reduction is incentive for N 2 O emissions fall. N 2 O is one of the most prominent greenhouse gases, and the increase in N 2 O emissions not only triggers global warming, but also leads to excessive atmospheric NO x levels and various air pollution. Research on the relationship between N 2 O emissions and resource utilization is scarce worldwide. We constructed an N 2 O emission accounting model for energy utilization based on emission sources and data availability in Guangdong Province, and explored the policies applicable to the sectoral emission reduction. We found that the pandemic-induced reduction in industrial and transportation activities resulted in a significant reduction of N 2 O emissions, waste combustion brought about by urban economic development is an important source of emission growth, energy utilization is the largest contributor to N 2 O emissions from 2019 to 2021, which has significantly dropped due to the reduction of labor force caused by social panic and the strict implementation of containment policies by the community. Our model highlighted a negative correlation between confirmed COVID-19 cases in 2020 and power generation deviation rates, emphasizing that the reduction of labor force caused by COVID-19 is a momentous factor for the decrease of power generation, which may be a prominence incentive for the fall of N 2 O emissions from fixed source combustion.