Observationally constrained global NOx and CO emissions variability reveals sources which contribute significantly to CO2 emissions
Shuo Wang, Jason Blake Cohen, Luoyao Guan, Lingxiao Lu, Pravash Tiwari, Kai Qin
Abstract
Global high-resolution emission inventories of trace gases require refinement to align with ground-based observations, especially for extreme events and changing sources. This study utilizes two satellites to globally quantify NO 2 and CO concentrations on daily to weekly scales and estimate emissions with uncertainty bounds, grid-by-grid, for regions with significant variability in 2010. These emissions demonstrate overall increased emissions and identify missing sources compared with various inventories. The NO x and CO emissions are 5.76 × 10 5 –6.25 × 10 6 Mt/yr and 1.06 × 10 7 –2.78 × 10 7 Mt/yr, representing a mean 200% and 130% increase. Significant emissions originate from typical and atypical sources, exhibiting short-to-medium-term variability, primarily driven by biomass burning and anthropogenic activities, with substantial redistribution and compression due to long-range transport. The extra CO emissions chemically decay into CO 2 , resulting in an increase in CO 2 mass equivalent to 3.5% of CO 2 emissions from Central Africa and 6.1% from Amazon, reflecting the importance of addressing CO from biomass burning.