Fig. 7: Climate, geomorphic activity, and eolian sediment transport in SW North America.
From: Higher interglacial dust fluxes relative to glacial periods in southwestern North American deserts
a Hillslopes are generally stable during glacial periods, limiting fine sediment delivery to and exposure on alluvial systems. Pluvial lakes limit playa emissions. High baseflow conditions erode fluvial tributaries and deliver sediment to mainstem floodplains, where they contribute to dust emission. (MIS = Marine Isotope Stage). b Glacial-to-interglacial transitions lead to widespread geomorphic instability on hillslopes. Hillslope sediments are transported downstream into alluvial systems and terminal basins, where they become exposed, promoting dust emission. c Following this initial pulse of sediment, interglacial periods are marked by more supply-limited conditions on alluvial and playa dust sources. Low baseflow conditions confine products of hillslope erosion to tributaries, limiting fluvial dust source emissions.
