“…In areas such as southern France (Carozza et al, 2015) and Italy (Leonardi et al, 2015;Pacciarelli et al, 2015;Stoddart et al, 2019) the transition from the Chalcolithic to the Bronze Age occurred around this time. The more generally discussed changes putatively relating to the 4.2 ka event occurred within the Bronze Age societies of the eastern Mediterranean (e.g., Jung and Wenninger, 2015;Adams, 2017;Lawrence et al, 2021;Palmisano et al, 2021), as the transition to the Bronze Age occurred earlier here. The end of the Old Kingdom in Egypt has long been suggested to relate to aridity at 4.2 ka (e.g., Bell, 1971;Williams, 2019), as has the collapse of the Akkadian Empire (e.g., deMenocal, 2001;Weiss, 2015Weiss, , 2016Weiss, , 2017.…”