Abstract: Accurately assessing the relationship between tree growth and climatic factors is of great importance in dendrochronology. This study evaluated the consistency between alternative climate datasets (including station and gridded data) and actual climate data (fixed-point observations near the sampling sites), in northeastern China’s warm temperate zone and analyzed differences in their correlations with tree-ring width index. The results were: (1) Gridded temperature data, as well as precipitation and relative humidity data from the Huailai meteorological station, was more consistent with the actual climate data; in contrast, gridded soil moisture content data showed significant discrepancies. (2) Horizontal distance had a greater impact on the representativeness of actual climate conditions than vertical elevation differences. (3) Differences in consistency between alternative and actual climate data also affected their correlations with tree-ring width indices. In some growing season months, correlation coefficients, both in magnitude and sign, differed significantly from those based on actual data. The selection of different alternative climate datasets can lead to biased results in assessing forest responses to climate change, which is detrimental to the management of forest ecosystems in harsh environments. Therefore, the scientific and rational selection of alternative climate data is essential for dendroecological and climatological research.

Key words: Climate data representativeness, Alternative climate data selection, Response differences, Deciduous broad-leaf forest, Warm temperate zone