Attribution of trends in meteorological drought during 1960-2016 over the Loess Plateau,China

• 作者: GUO Mengyao SHE Dunxian ZHANG Liping LI Lingcheng YANG Zong-Liang HONG Si
• 来源期刊: 地理学报（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: Special Issue:Ecohydrology
• 页码范围: 1123-1139
• 页数: 17页
• 语种: 英文
• DOI: 10.1007/s11442-021-1888-y

摘要

This study uses two forms of the Palmer Drought Severity Index (PDSI),namely the PDSI_TH (potential evapotranspiration estimated-by the Thornthwaite equation) and the PDSI_PM (potential evapotranspiration estimated by the FAO Penman-Monteith equation),to characterize the meteorological drought trends during 1960-2016 in the Loess Plateau (LP)and its four subregions.By designing a series of numerical experiments,we mainly investi-gated various climatic factors' contributions to the drought trends at annual,summer,and autumn time scales.Overall,the drying trend in the PDSI_TH is much larger than that in the PDSI_PM.The former is more sensitive to air temperature than precipitation,while the latter is the most sensitive to precipitation among all meteorological factors.Increasing temperature results in a decreasing trend (drying) in the PDSI_TH,which is further aggravated by de-creasing precipitation,jointly leading to a relatively severe drying trend.For the PDSI_PM that considers more comprehensive climatic factors,the drying trend is partly counteracted by the declining wind speed and solar radiation.Therefore,the PDSI_PM ultimately shows a much smaller drying trend in the past decades.