A 219-year reconstruction of April-June mean minimum temperature from the tree-ring earlywood density on the Changbai Mountains, China

Using mean earlywood density data from Pinus koraiensis cores, we reconstructed the April-June mean minimum temperature from 1797 to 2015 for the Changbai Mountains. The reconstruction explained 52.6% of the actual mean minimum temperature variance during 1901-2015. After smoothing with an 11-year moving average, we identified three major cold periods (1797-1875, 1881-1899, and 1903-1946) and three major warm periods (1876-1880, 1900-1902, and 1947-2015) in the reconstructed series. Spatial correlation showed that the reconstruction contained climatic signals for a large area including most of northeast China, especially the Bohai Rim region and the eastern side of the Mongolian Plateau. A comparison between the newly reconstructed temperature series for the surrounding areas reveals similar variations, particularly in the warming trend during the second half of the 20th century. The driving factors of the mean minimum temperature were influenced mainly by the interaction of solar activity and large-scale atmospheric-oceanic variability. The reconstructed series provides a basis for understanding past climate change in the Changbai Mountains and for predicting future climate change trends in Northeast China.