LAUSR

© 2019 American Meteorological Society For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy. L ate spring (April–May) is normally the end of the dry season in South China, but 2018 was an exception. An extreme drought condition developed over South China (22°–29°N, 105°–120°E; box in Figs. 1a–c) during the late spring in 2018, affecting the provinces of Guangdong, Fujian, Jiangxi, Guizhou, and part of Hunan. South China received only about 40% of the 1951–2018 mean precipitation over Guangdong and Fujian provinces (Fig. 1a). The surface temperature reached 2.8°C above normal (1951–2018 mean) at a maximum (Fig. 1b), with record-breaking hot days in May reported in Guangdong, Jiangxi, and Fujian provinces. More than half stations over South China experienced a record-breaking drought seen from the anomalies in precipitation and the difference between precipitation and reference evapotranspiration (Pr-ET) (Figs. 1a,c). The 2018 late spring was ranked as the third year with extreme deficit rainfall (−2.6 mm day−1 less), the warmest year (2.0°C warmer) for 1951–2018 (Fig. 1d), and the second driest year on record (−2.8 mm day−1 less) measured by Pr-ET. It reported that this drought has resulted in shrinking reservoirs and water shortages (www.gdsw.gov.cn/zwgk_tjxx.html; http://slt. fujian.gov.cn/xxgk/tjxx/swxb/). The acreage and yield for early rice, which is mainly planted in South China, was reduced respectively by 350 thousand hectares and 1.28 million tons relative to 2017 (National Bureau of Statistics of China; www.stats.gov.cn/tjsj/ zxfb/201808/t20180824_1618794.html). Observations show that South China has experienced a drying trend in late spring since the 1950s (Xin et al. 2006; Qiu et al. 2009; Li et al. 2018). The internal variation, such as the interdecadal changes of North Atlantic Oscillation (Xin et al. 2006) and an increase in protracted El Niño events accompanied by a reduction in La Niña episodes (Qiu et al. 2009), and anthropogenic aerosol forcing (Kim et al. 2007) were documented to be contributing to this drying trend. So far it is still unclear whether the attribution of anthropogenic forcing is detectable in the extreme late spring drought events over South China. This study will investigate the cause of the 2018 late spring drought in South China, and will assess the contribution of anthropogenic climate change on the likelihood of the 2018 late spring drought over South China by both examining drought indices and associated circulation.