The difference in viscosity for the two phases (Fig. ) highlights global regions wherein the prevalence of LLPS may be of greater importance for atmospheric process. For many regions of the troposphere, including much of the planetary boundary layer (<1 km altitude) and in polar regions at all altitudes, there is between two and six orders of magnitude difference between the viscosities of the two phases of BBOA (Fig. ). For these conditions, the higher viscosity of the outer hydrophobic phase could significantly impact atmospheric processes, as discussed below.