Modeling the climatic implications and indicative senses of the Guliya δ18O-temperature proxy record to the ocean–atmosphere system during the past 130 ka
Abstract. Using an intermediate-complexity UVic Earth System Climate Model (UVic Model), the geographical and seasonal implications and indicative senses of the Guliya temperature proxy found in the Guliya δ18O ice core record (hereinafter, the Guliya δ18O-temperature proxy record) are investigated under time-dependent orbital and CO2 forcings with an acceleration factor of 50 over the past 130 ka. The results reveal that the simulated August–September Guliya surface air temperature (SAT) reproduces the 21-ka precession and 43-ka obliquity cycles of the Guliya δ18O-temperature proxy record, showing an in-phase variation with the latter. Moreover, the Guliya δ18O-temperature proxy record may be also an indicator of the August–September Northern Hemispheric (NH) SAT. Corresponding to the difference between the extreme warm and cold phases of the precession cycle in the Guliya August–September SAT, there are two anomalous patterns in SAT and sea surface temperature (SST). The first anomalous pattern shows increases of SAT and SST toward the Arctic, which is possibly associated with an increase of the NH incoming solar radiation that is caused by the in-phase superposition between the precession and obliquity cycles. The second anomalous pattern shows increases of SAT and SST toward the equator, which is possibly due to a decrease of incoming solar radiation over the NH polar that results from the anti-phase counteraction between the precession and obliquity cycles. The summer (winter) Guliya and NH temperatures are higher (lower) in the warm phases of the August–September Guliya than in their cold phases. Moreover, in August–September, the Guliya SAT is closely related to the North Atlantic SST, in which the Guliya precipitation might act as a "bridge" linking the Guliya SAT and the North Atlantic SST.