Ground surface temperature change and its driving mechanisms in the eastern Taklimakan Desert based on a 188 year tree-ring record

The Taklimakan Desert is the largest desert in China. High temperatures pose a deadly threat to the fragile ecosystems in the desert, but the long-term temperature changes are unclear, which seriously affects the decision-making on desert control and ecological restoration. This study constructed a tree-ring width chronology of Populus euphratica in the lower Tarim River to investigate the impact of surface air temperature (SAT) and ground surface temperature (GST) on the growth of P. euphratica. Correlation analysis indicated that high summer temperatures significantly inhibit the growth of P. euphratica, especially high GST. On this basis, we reconstructed the GST from May to July in the lower Tarim River over the past 188 years. The reconstruction explained 52.7% of the variance in observed data and revealed a significant warming trend starting from the 1940s. The combination of reconstruction and observational data revealed that changes in GST in the past 20 years have exceeded the range of variation in the past 200 years and that GST is increasing at a rate far exceeding SAT in recent decades. Analysis showed that Atlantic Multidecadal Oscillation (AMO), circumglobal teleconnection (CGT) and westerly winds are the main drivers of GST changes in the eastern Taklamakan Desert. AMO affected the CGT wave train on the interdecadal scale and thus affected the GST. This study reveals the impact of GST on tree growth in the desert and the possible driving mechanisms of GST changes in the Tarim Basin, which should guide the desert’s ecological restoration and climate prediction.