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Secondary organic aerosol (SOA) affects the earth's radiation balance and global climate. High-elevation areas are sensitive to global climate change. However, at present, SOA origins and seasonal variations are understudied in remote high-elevation areas. In this study, particulate samples were collected from July 2012 to July 2013 at the remote Nam Co (NC) site, Central Tibetan Plateau and analyzed for SOA tracers from biogenic (isoprene, monoterpenes and β-caryophyllene) and anthropogenic (aromatics) precursors. Among these compounds, isoprene SOA (SOA_I) tracers represented the majority (26.6 ± 44.2 ng m⁻³), followed by monoterpene SOA (SOA_M) tracers (0.97 ± 0.57 ng m⁻³), aromatic SOA (SOA_A) tracer (2,3-dihydroxy-4-oxopentanoic acid, DHOPA, 0.25 ± 0.18 ng m⁻³) and β-caryophyllene SOA tracer (β-caryophyllenic acid, 0.09 ± 0.10 ng m⁻³). SOA_I tracers exhibited high concentrations in the summer and low levels in the winter. The similar temperature dependence of SOA_I tracers and isoprene emission suggested that the seasonal variation of SOA_I tracers at the NC site was mainly influenced by the isoprene emission. The ratio of high-NO_x to low-NO_x products of SOA_I (2-methylglyceric acid to 2-methyltetrols) was highest in the winter and lowest in the summer, due to the influence of temperature and relative humidity. The seasonal variation of SOA_M tracers was impacted by monoterpenes emission and gas-particle partitioning. During the summer to the fall, temperature effect on partitioning was the dominant process influencing SOA_M tracers' variation; while the temperature effect on emission was the dominant process …