How the genomic diversity of species is driven by geographical isolation and environmental factors are not well understood for cold environments. Here, the environmental stress responses of two phylogenetically close Arcticibacter strains, A. eurypsychrophilus MJ9-5 and A. svalbardensis MN12-7, isolated from a Tibetan Plateau glacier and Svalbard soil, were analyzed. The comparative genomic analysis was performed with sixteen other related Sphingobacteriaceae species. Analyses of the relationships between growth temperature and genome composition, cold and heat shock genes showed that genomic adaption characteristics were more obvious when the strains were grouped by their upper limit in growth temperature, rather than by their minimal or optimal growth temperatures for Sphingobacteriaceae species. The very divergent genetic distance of genome fractions assigned to the functions of ‘secondary metabolism’, ‘dormancy and sporulation’ and ‘metabolism of aromatic compounds’ indicated the heterogeneous evolution of genes under different environmental pressures of the Sphingobacteriaceae species. The greatest differences between strains MJ9-5 and MN12-7 occurred in the genes devoted to the CRISPRs, osmotic adaption and metabolism of monosaccharides, nitrogen and aromatic compounds. These distinctions corresponded to two different environmental pressures, salinity and nutritional level, in the glacier ice and Svalbard soil environments.

Two annually resolved ice core records, one drilled on Mutztagata (7,000 m above sea level) on the western slope (dated 1952–2002) and the other drilled on Kuokuosele (5,600 m above sea level) on the southwestern slope (dated 1900–2010) of the Pamir Plateau of the northwestern Tibetan Plateau (TP), were selected to study possible El Niño–Southern Oscillation (ENSO) influences on the northwestern TP. δ¹⁸O at KKSL was more enriched, though both records varied in phase. Eight of the 10 noticeably strong El Niño events since 1955 corresponded to δ¹⁸O depletions in both ice core records, which were followed by δ¹⁸O enrichment. Atmospheric circulation indices, including water vapor flux and divergence, had a coincidence of a positive Indian Ocean Dipole mode with El Niño events, which contributed to the northward transport of southerly flows from the western Indian Ocean; its convergence with midlatitude wind flows at high levels depleted δ¹⁸O levels. The meridional shift in the Asian‐Pacific subtropical high induced by latent heat release due to precipitation in the northwestern Pacific was found to play an important role in initiating convergence. A statistical analysis confirmed the significant correlations in δ¹⁸O with the ENSO index and tropical and subtropical summer monsoon circulations. We noted that the dominant circulation pattern over the northwestern TP was characterized by a midlatitude flow regime that had a teleconnection with tropical sea surface temperatures. Therefore, ENSO is one of a variety of influences on ice core δ¹⁸O on the TP.