Fig. 2: Seasonal δ18Op variations and its decomposition in N. China and S. China.

a Seasonal δ18Op anomaly (bold black line) and its source decomposition (non-black lines) in N. China. b Contribution of moisture source change to the δ18Op anomaly (\({\Delta }_{{{\rm{dP}}}_{{\rm{Ori}}}}\), bold black line) and the source decomposition of \({\Delta }_{{{\rm{dP}}}_{{\rm{Ori}}}}\) (non-black lines) in N. China. c Contribution of isotope change from source regions to the δ18Op anomaly (Δdδ, bold black line) and the source decomposition of Δdδ (non-black lines) in N. China. d Same as (a) but for S. China. e Same as (b) but for S. China. f Same as c but for S. China. In each region, \({{\rm{\delta }}}^{18}{{\rm{O}}}_{{\rm{p}}}={\Delta }_{{{\rm{dP}}}_{{\rm{Ori}}}}+{\Delta }_{\text{d}{\rm{\delta }}}\). PO the Pacific Ocean, IO the Indian Ocean, AO the Atlantic Ocean, EAS East Asia Continent, EC the Eurasian Continent, Other, the remaining other tagging regions. The bold black line in each panel represents the total δ18Op anomaly, \({\Delta }_{{{\rm{dP}}}_{{\rm{Ori}}}}\), or Δdδ for each study regions.