Table 1.

Measurement – inventory comparison (i.e. measured/modelled flux (emission) ratio). The uncertainty range is given by sub- and superscripts. PC: passenger cars; LCV: light commercial vehicle.

Measurement/inventory ratio or Measurement/emission standard ratio		NOx/CO2 NOx/CO	NOx/benzene
INNAQS/COPERT1,#		${1.7}_{1.6}^{1.8}$	${3.9}_{3.1}^{4.7}$
INNAQS/HBFA3.22		${1.5}_{1.4}^{1.6}$	N/A
INNAQS/ACCMIP (traffic)3		${4.0}_{2.8}^{5.3}$*	${2.1}_{1.7}^{2.5}$
INNAQS/EMEP (traffic)#		${2.9}_{2.6}^{3.3}$*	N/A
INNAQS/US Tier II4		${36.0}_{33.4}^{38.6}$	N/A
		NOx/CO2 PC and LCV < 1305 kg	NOx/CO2 LCV 1305 kg–3500 kg
INNAQS/Euro65	Diesel	${4.7}_{4.3}^{5.0}$	${4.5}_{4.1}^{4.8}$
	Petrol	${12.6}_{11.7}^{13.5}$	${19.5}_{18.1}^{20.9}$
INNAQS/Euro55	Diesel	${2.1}_{1.9}^{2.3}$	${2.0}_{1.8}^{2.1}$
	Petrol	${12.6}_{11.7}^{13.5}$	${19.5}_{18.1}^{20.9}$
INNAQS/Euro45	Diesel	${1.5}_{1.4}^{1.6}$	${1.4}_{1.3}^{1.5}$
	Petrol	${4.7}_{4.4}^{5.0}$	${14.5}_{13.5}^{15.5}$
INNAQS/Euro35	Diesel	${0.75}_{0.7}^{0.8}$	${0.9}_{0.85}^{1.0}$
	Petrol	${2.5}_{2.3}^{2.7}$	${18.0}_{16.7}^{19.3}$

¹COPERT emission model (SI).

²HBFA 3.2 (SI). Comparison with HBFA 3.3, that was published during the copy editing phase, yielded an average bias of 1.2.

³ACCMIP – (SI).

⁴US EPA²².

⁵EEA²⁴.

*For inventories that do not explicitly report CO₂, we converted data using the measured midday range of CO to CO₂ flux ratios (3.6 to 4.6 ppbv/ppmv), which fall close to a recent evaluation based on a road tunnel study⁴⁵.

^#Data are trend adjusted for 2015 according to GAINS (http://gains.iiasa.ac.at/models/)²³.