Anthropogenic aerosols (AER) and greenhouse gases (GHG) – the leading drivers of the forced historical change – produce different large-scale climate response patterns, with varying trend pattern correlations from negative to positive over the past century. To understand what caused the time-evolving comparison between GHG and AER responses, we apply a joint low-frequency component analysis on global sea-surface temperature and sea-surface salinity response over 1921-2020 from CESM1 single-forcing large ensemble simulations. While GHG response is well-described by its first leading mode, AER response consists of two distinct modes. The first one features global AER increase and global cooling, opposite to GHG-induced warming. The second mode features multidecadal variations in AER distributions, where the recent shift from North America/western Europe to southeast Asia emissions drives regional changes enhancing the GHG effect. We argue that AER can have both competing and synergistic effects with GHG, as their emissions change temporally and spatially.