Analysis of the water balance of the southwestern United States (SWUS) during 1900 through 2018 was used to evaluate the magnitude of the turn-of-the-century (TOC) drought in the SWUS. Results indicate that the warm season (April through September) soil moisture and runoff during the TOC drought were among the lowest values of the 1900 through 2018 period. Additionally, increases in temperature were identified as a significant driver of low soil moisture and runoff conditions during the warm season. In contrast, during the cool seasons (October through March) and the water year (October 1 through September 30) during the TOC drought, soil moisture and runoff did not indicate extremely dry conditions even though temperatures were the highest of the 1900 through 2018 period.

1900 年至 2018 年美国西南部 (SWUS) 的水平衡分析用于评估 SWUS 世纪之交 (TOC) 干旱的严重程度。结果表明，TOC 干旱期间暖季（4 月至 9 月）土壤水分和径流是 1900 年至 2018 年期间的最低值。此外，温度升高被确定为温暖季节土壤水分和径流条件低的重要驱动因素。相比之下，在 TOC 干旱期间的凉爽季节（10 月至 3 月）和水年（10 月 1 日至 9 月 30 日）期间，即使温度是 1900 年至 2018 年期间的最高值，土壤水分和径流也没有表现出极度干燥的条件.