“…Second, the frequent associations with summer‐season changes in groundwater elevations likely reflect root access to soil moisture. Such access is often argued to be the greatest limiting factor for plant growth in semi‐arid Mediterranean environments (Newman et al, 2006; Torres‐García et al, 2021), but as the multi‐decadal analysis demonstrates here, there is additionally an over‐riding need for winter storms to drive groundwater recharge in areas such as southern California that are subject to high interannual flow variability. This phenomenon has also been documented along other intermittent and dryland rivers around the globe (Scanlon et al, 2006), including systems within Africa (Cuthbert et al, 2019; Lange, 2005), Brazil (Costa et al, 2013), China (Qin et al, 2012) and Australia (McCallum et al, 2014).…”