A 250-Year Winter Minimum Temperature Reconstruction Based on Tree Rings from Luoji Mountain, Southwest China

Annually resolved temperature records spanning the past few centuries are limited in Southwest China. In this paper, we present a robust 250-year winter minimum temperature reconstruction based on the tree rings of Abies georgei Orr from Luoji Mountain, Southwest China. The tree rings exhibit significant correlations with winter minimum temperatures (Tmin) from the previous November to the current March (pNov-cMar). Based on this relationship, we reconstructed pNov-cMar Tmin from 1765 to 2014. This reconstruction accounts for 37.8% of the Tmin variance during the instrumental 1960-2014 period. Our reconstruction reveals five warm periods (1765-1785, 1795-1804, 1827-1883, 1901-1907, 1989-2014) and four cold periods (1786-1794, 1805-1826, 1884-1900, 1908-1988) over the past 250 years. Spectral analyses revealed several significant interannual (2.3-2.4a, 3.9-4.2a, 8.9-9.7a) and interdecadal (23.0-28.9a) cycles in our reconstruction series. Both spatial correlation analysis and the inter-comparison of paleoclimate records revealed that the winter Tmin reconstruction had significant positive correlations with the Atlantic Multidecadal Oscillation (AMO), with relatively consistent warm and cold periods in their variations over the past 250 years.