Assessing the optimized precision of the aircraft mass balance method for measurement of urban greenhouse gas emission rates through averaging

摘要: To effectively address climate change, aggressive mitigation policies need to be implemented reduce greenhouse gas emissions. Anthropogenic carbon emissions are mostly generated from urban environments, where human activities spatially concentrated. Improvements in uncertainty determinations and precision of measurement techniques critical permit accurate precise tracking changes relative the reduction targets. As part INFLUX project, we quantified dioxide (CO 2 ), monoxide (CO) methane (CH 4 ) emission rates for city Indianapolis by averaging results nine aircraft-based mass balance experiments performed November-December 2014. Our goal was assess achievable method through averaging, assuming constant CO , CH during a three-week field campaign late fall. The leads an rate 14,600 mol/s assumed largely fossil-derived this period year, 108 CO. standard error mean is 17% 16%, CO, respectively, at 95% confidence level (CL), i.e. more than 2-fold improvement previous estimate ~40% single-flight measurements Indianapolis. For averaged 67 mol/s, while CL large, ±60%. Given same flight data, conclude that much larger scatter observed most likely due variability emissions, suggesting assumption daily not correct sources. This work shows repeated using methods can yield sufficient inform efforts detecting over time