英文摘要: |
This paper provides the first interannual variability of PDSI series in Central Inner Mongolia, China.
A Pinus tabulaeformis tree-ring-width chronology in Baotou, China, was developed. Based on the chronology, we reconstructed the local interannual variability of the Palmer Drought Severity Index (PDSI) from the previous September to current July (PDSIp9-7) for the past 278 years. The reconstruction explained 41.3% of the variance (40.3% after adjusting the degrees of freedom) of the actual interannual variability of the PDSI during the calibration period (1951-2012 AD). The spectral analyses revealed 3.5-, 2.6-, 2.3-, 2.1- and 2-year quasi-cycles at a 95% confidence level and 7.9-, 7.1- and 5.2-year quasi-cycles at a 90% confidence level. The PDSI reconstruction series was consistent with several reconstructed climatic series based on the tree-ring chronology in neighboring regions. The PDSIp9-7 exhibits excellent regional representativeness, which indicates the consistency of the drought variation of the central part of the monsoon margin area in north China, whereas PDSIp9-7 can represent the drought history of the central part of the north monsoon margin area. In addition, significant relationships were found between the PDSIp9-7 series and the Arctic Oscillation, North Atlantic Oscillation, El Nio-Southern Oscillation and Pacific Decadal Oscillation series, which indicates that the PDSI variation in the study area was influenced by a combination of these factors. |