The aerosol size distribution of aerosols with electrical mobility diameter between 8.5 and 700 nm (14 size bins centered on 10, 13.7, 18.8, 25.7, 35.2, 48.3 66.2, 90.7, 124.2, 170.2, 233.2, 319.6, 437.9, and 600 nm) was measured with a custom-built differential mobility particle sizer (DMPS), which performs one complete scan every ~ 460 seconds. This instrument was previously used to study new particle formation on La Réunion Island and has been described in detail elsewhere . Briefly, particles are first charged to equilibrium using a Ni-63 bipolar charger, after which they enter the DMPS, which includes a TSI-type differential mobility analyzer operating in a closed loop and a TSI 3010 condensation particle counter. The instrument was operated behind a whole air inlet (higher size cut-off of 25 μm for an average wind speed of 4 ms -1 ), and measurement protocols were defined with respect to the ACTRIS (Aerosol, Clouds and Trace Gases Research Infrastructure) recommendations regarding both the flow rates and relative humidity 32 . Based on the intercomparison study from Wiedensohler et al. (2012) , we assign a relative uncertainty of 10% (k = 2) to the aerosol size distribution in the 20 -200 nm size range, and 30% outside this range.