How have Quaternary climate changes affected playa lakes?

Playas are exceptionally sensitive to environmental shifts, and they have been profoundly influenced by the hydrologic changes of the Quaternary Period (the past 2.6 million years).1

During this time, all playas experienced episodes of expanded lake levels, often referred to as pluvial lakes. These expansions were likely driven by increased rainfall, though they may also have resulted from higher groundwater inflow or reduced evaporation and transpiration. The resulting sedimentary sequences often contain alternating layers of lacustrine clays, which reflect these periods of high floodwater runoff, and salt beds, which indicate arid climatic phases.12

Modern geochronologic techniques, such as radiocarbon dating, have allowed scientists to map these fluctuations. For example, in northern Africa, lakes reached maximum high levels between 10,000 and 8,000 years ago, while many southwestern United States lakes achieved their most recent high levels between 14,000 and 11,000 years ago. Conversely, during the coldest, driest phases of the last glacial period, many of these basins experienced significant desiccation, leading to the formation of the modern playa surfaces observed today.32