Liu Dong-Ming, Ji Rui-Peng, Chen Peng-Shi, Zhang Wei-Wei, Li Jing
Institute of Atmospheric Environment, China Meteorological Administration, Shenyang 110166, China.
Ecological Meteorology and Satellite Remote Sensing Center of Liaoning Province, Shenyang 110166, China.
Ying Yong Sheng Tai Xue Bao. 2020 Oct;31(10):3480-3488. doi: 10.13287/j.1001-9332.202010.011.
The evaporative demand drought index (EDDI) is a multi-scale drought index developed from the atmospheric evaporation demand (). EDDI is independent of precipitation and suitable to different underlying surfaces, which can well capture water stress signals at different time scales. Based on the meteorological observation data at 52 stations in Liaoning Province from 1961 to 2018, we estimated daily , calculated EDDI at six time scales (annual, growing season, spring, summer, autumn and winter), and further identified the interannual variability of drought occurrence in Liaoning Province for the past 58 years. The results showed that EDDI had obvious interannual variation, with two high concentration periods in multiple time scales. In the 1960s, when there were many years and serious drought in Liaoning Province, high EDDI values were concentrated at the five time scales (annual, growing season, spring, autumn and winter). 2014-2018 was another relatively concentrated period of EDDI high value at all time scales except winter. In 1981-1982, the values of EDDI were high at the time scales of the annual, growth season, summer and autumn. The periods of 1963-1965 (except summer), 1972-1973 (growth season, summer), 1989-1990 (annual, growth season, spring and winter), 1997-1998 (annual, growth season and summer), 2004-2005 (spring and winter) and 2013-2014 (annual, growth season and autumn) occurred abrupt alternation from dry to wet or from wet to dry. In 1985-1987, 1993-1995 and 2005-2013, Liaoning Province had obvious dry gaps.
蒸发需求干旱指数（EDDI）是一种基于大气蒸发需求开发的多尺度干旱指数。EDDI与降水无关，适用于不同的下垫面，能够很好地捕捉不同时间尺度上的水分胁迫信号。基于辽宁省52个站点1961—2018年的气象观测数据，我们估算了逐日蒸发需求，计算了六个时间尺度（年、生长季、春季、夏季、秋季和冬季）的EDDI，并进一步识别了辽宁省过去58年干旱发生的年际变化。结果表明，EDDI具有明显的年际变化，在多个时间尺度上存在两个高值集中期。20世纪60年代，辽宁省干旱年份多且严重，EDDI高值集中在年、生长季、春季、秋季和冬季这五个时间尺度上。2014—2018年是除冬季外所有时间尺度上EDDI高值的另一个相对集中期。1981—1982年，年、生长季、夏季和秋季时间尺度上的EDDI值较高。1963—1965年（夏季除外）、1972—1973年（生长季、夏季）、1989—1990年（年、生长季、春季和冬季）、1997—1998年（年、生长季和夏季）、2004—2005年（春季和冬季）以及2013—2014年（年、生长季和秋季）出现了干湿突变。1985—1987年、1993—1995年和2005—2013年，辽宁省存在明显的干旱期。
