Spatiotemporal Characteristics of Drought Occurrences over Japan

• DOI: 10.1175/jamc-d-11-0157.1
• Publication Date: 2012-03-07T14:52:21Z
• Authors: Sang-Min Lee; Hi-Ryong Byun; Hiroshi L. Tanaka
• Keywords: Wet season; Dry season

Abstract The drought climate of Japan from 1902 to 2009 was analyzed using an effective index (EDI). Drought regions were identified by hierarchical cluster analysis characteristics (duration, severity, and onset end dates) obtained 50 observation stations. results indicated that droughts could be divided into four groups (G1–G4) reflected the local climate. related precipitation as follows. summer rainy season affected G2–G4, in which occurred mainly during spring relieved before after season. G1 group not spread evenly throughout year; it even had cases winter snow. All included dry conditions over 108-yr period, driest late twentieth century. statistical data showed a total 23 country-wide most extreme 1939–41 1984–85, with EDI −1.55. In addition, seasons (1939–45, 1997–98, 1994–97, 2005–09) found regime shift analysis. Regional 54, 49, 59 times G1–G4, respectively. On average, short-term duration shorter than 6 months 3.5 per decade, whereas long-term extending 1 yr 0.3 decade. intensity used calculate return period droughts. longest at 104.7 yr. 1987–88 1995–97 periods 65.9 65.5 yr,