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To evaluate the applicability of the Standardized Precipitation-Evapotranspiration Index(SPEI) and the self-calibrated Palmer Drought Severity Index(sc PDSI) to paleoclimate reconstructions in the east Asian summer monsoon region, we used a 194-year tree-ring width chronology from Guancen Mountain, Shanxi Province,China, to investigate its correlation with SPEI and sc PDSI,respectively. The results indicated sc PDSI as a robust drought index that could be reconstructed from tree-ring width on Guancen Mountain. Significant correlations with other hydroclimate-related series illustrated that our reconstruction captured common variations of hydroclimate in the surrounding areas. Additionally, our reconstructionshowed significant correlation with nearby grid points of the Monsoon Asia Drought Atlas(MADA). However,while unprecedented drying trend existed during the past several decades in MADA, it was not represented in our reconstruction or in instrumental sc PDSI/Dai-PDSI. This may imply that MADA overestimated drought severity during the past several decades in our study area; this overestimation was probably caused by an insufficient spatiotemporal distribution of the tree-ring network used by MADA. Therefore, more drought reconstructions based on individual sampling sites in eastern Asia are necessary to gain a thorough understanding of the Asian Monsoon climate variability.
To evaluate the applicability of the Standardized Precipitation-Evapotranspiration Index (SPEI) and the self-calibrated Palmer Drought Severity Index (sc PDSI) to paleoclimate reconstructions in the east Asian summer monsoon region, we used a 194-year tree-ring width chronology from Guancen Mountain, Shanxi Province, China, to investigate its correlation with SPEI and sc PDSI, respectively. The results indicated sc PDSI as a robust drought index that could be reconstructed from tree-ring width on Guancen Mountain. Significant correlations with other hydroclimate-related series illustrated that our reconstructed common variations of hydroclimate in the surrounding areas. Additionally, our reconstructionshowed significant correlation with nearby grid points of the Monsoon Asia Drought Atlas (MADA). However, while yet drying drying in the past during the past several decades in MADA, it was not represented in our reconstruction or in instrumental sc PDSI / Dai-PDSI. This May imply that MADA overestimated drought severity during the past several decades in our study area; this overestimation was probably caused by an insufficient spatiotemporal distribution of the tree-ring network used by MADA. Therefore, more drought reconstructions based on individual sampling sites in eastern Asia are necessary to gain a thorough understanding of the Asian Monsoon climate variability.