Fig. 6: Dependence of the apparent ice emission index on the nvPM emission index.
From: Fuel sulfur content can modulate contrail ice crystal numbers

Dependence of contrail AEI on nvPM EI (lines) at 100% RHi for the tested fuels, as simulated by the ACM model. Symbols represent mean AEI from far-field (95% < RHi < 100%) vs. nvPM emission indices from near-field measurements, including uncertainty interval. The gray dashed line represents the 1:1 relationship between AEI and nvPM EI.