June–September mean temperature variability in the eastern Qinghai-Tibet Plateau over the past 225 years based on high quality tree-ring records

Abstract

Being one of the most high-resolution climate proxies, tree-rings have been extensively used in paleoclimate studies, and help forecast future global warming and patterns of climate change. However, most climate reconstructions based on tree-ring data explain less than 50 % of the variance observed in meteorological station records, and high-quality chronologies are essential for a reliable assessment of climate change. Here, we present a new June–September mean temperature reconstruction over the past 225 years (1796–2020 CE) using Abies faxoniana tree-ring width data from the eastern Qinghai-Tibet Plateau, which explains 67.4 % of the instrumental temperature variations during 1960–2020 CE (r = 0.82, p < 0.001). This reconstruction shows significant (p < 0.01) spatial representativeness for June–September temperature variations in the eastern Qinghai-Tibet Plateau and allows identification of significant (p < 0.05) cycles at 2–4-, 54-, 79-, and 128-year periodicities. Three obvious cold periods in 1810s–1820s, 1910s–1930s, and 1960s–1980s were likely related to low solar activity and frequent volcanic eruptions, negative phases of Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation, and enhanced anthropogenic aerosol-induced radiation dimming, respectively. Consistency with nearby temperature reconstructions and divergence with the Northern Hemisphere temperature variations suggest that more regional and high-quality tree-ring-based climate research should be conducted to advance our knowledge of climate variability.