Size-resolved microphysical and optical properties of atmospheric aerosols in Golmud, an urban area of the northern Tibetan Plateau

The measurements were obtained using a tandem system composed of a TSI 3081 differential mobility analyzer (DMA) connected in series with a TSI 3775 condensation particle counter (CPC, TSI Inc., Shoreview, MN, USA) and a version C SP2 (Droplet Measurement Technologies, Boulder, CO, USA).The tandem measurement system provides aerosol number concentrations at each selected particle size (SizeResolvedConc_CPC.xlsx) and aerosol number concentrations classified by the SP2 into different types: BC-free (black carbon-free), thickly-coated BC, and thinly/uncoated BC (SizeResolvedConc_SP2.xlsx).

Following the algorithm by Hagen and Alofs (1983), the discrete aerosol number concentrations were inverted to derive aerosol number size distributions (dNdlnD_CPC.xlsx, dNdlnD_SP2.xlsx). Both the SizeResolvedConc_SP2.xlsx and dNdlnD_SP2.xlsx data files contain six sheets labeled "all," "sca," "inc," "lag," "tct," and "leo," representing all particles detectable by the SP2, scattering-only particles (BC-free), BC-containing particles, BC particles with resolvable mixing states, thickly-coated BC particles, and BC particles successfully fitted using LEO method, respectively.Supplementary data include the non-refractory chemical composition of PM2.5 measured by a Time-of-Flight Aerosol Chemical Species Monitor (ToF-ACSM, Aerodyne Research Inc., Billerica, MA, USA), along with the resolved organic aerosol sources: FFOA, COA, LO-OOA, and MO-OOA (ACSM_Golmud_202108_Igor8.xlsx).