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Wind is one of the major processes modifying the land surface in the Hami Basin, as evidenced by wind deflation gravel lags, yardangs, and gravel mantled eolian ripples. We report erosion rates for the Hami Basin using cosmogenic 10Be measurements. Bedrock erosion rates average 0.121 ± 0.0293 mm yr−1, which is similar to those of other wind‐eroded arid basins in East Asia, but is anomalously low when modern near‐surface wind speeds are considered. We posit that interglacial periods experienced lower erosion rates than glacial periods, and that the Hami Basin was likely once a larger dust producer than at present, with Pleistocene dust emissions driven by the eolian deflation of alluvial terrace deposits as well as bedrock weathering and abrasion. Wind erosion and dust production in the Hami Basin was largely regulated by the synoptically controlled spatial‐temporal distribution of precipitation and subsequent landscape evolution since at least the late Pleistocene. Plain Language Summary: The Hami Basin in Xinjiang, China is in the core of the >3 × 106 km2 arid to hyperarid dust generating corridor of the eastern Eurasian continental interior. Quantifying the wind abrasion of bedrock on long timescales, while challenging, is necessary to understand landscape evolution. Based on cosmogenic 10Be measurements of wind eroded bedrock features (i.e., yardangs) in the Hami Basin, we provide the first quantitative evaluation of bedrock erosion in the stony Hami Basin over the last ∼20 thousand years. Incorporating previous work with our erosion rates, the results indicate that wind erosion rates are lower now than over multiple previous glacial‐interglacial cycles in the Hami Basin. Key Points: Wind erosion rates in the Hami Basin were determined to be ∼0.121 mm yr−1 for the last ∼11–23 ky using cosmogenic 10Be measurementsInterglacial periods likely experienced lower erosion rates than glacial periods due to changes in atmospheric conditionsWind erosion and dust production were regulated by climate and landscape evolution since the late Pleistocene in the Hami Basin [ABSTRACT FROM AUTHOR]

Unconsolidated gravel surfaces, alluvial terraces, and yardangs are widespread in the Turpan-Hami topographical depression of NW China. These landscape features provide an opportunity to investigate the wind erosion history and landscape evolution of the Hami Basin. Along with anomalously high near-surface wind speeds, these features suggest that the Hami Basin was an important source of mineral dust during the Pleistocene. We present the results of an integrated geomorphologic, stratigraphic, and chronologic study on the genesis of unconsolidated gravel surfaces and yardang fields in the Hami Basin. Mobilization of silt- to sand-sized fractions from the surfaces of the Quaternary alluvial sediments occurred under generally dry conditions, leaving unconsolidated gravels to organize into inflationary-type desert pavement surfaces (Type-1) and deflationary-type desert pavements surfaces (Type-2). We propose that the Pleistocene alluvial terraces of the Hami Basin formed principally during wetter intervals, which are assumed to correspond with interglacial periods. The coarse-grained alluvium atop terraces protected underlying strata from wind erosion. The bedrock then began to be sculpted into yardangs after the removal of the coarse-grained armoring surfaces. With mostly sub-horizontal bedding, the geometries of yardangs was controlled by lithology, wind and water erosion. Based on UAV-3D models, optically-stimulated luminescence (OSL) and electron spin resonance (ESR) ages, we find an erosion rate of ~0.23 mm/yr since ~200 ka, This, combined with widespread uneroded strata armored by unconsolidated gravel surfaces, indicates that the Hami Basin had considerable dust emission potential in the past. • An integrated geomorphologic, stratigraphic and chronologic study on gravel surfaces. • Geometries and factors controlling yardang fields in deeply wind eroded strata. • Late Quaternary fluvial-eolian landscape evolution model for the Hami Basin. • A dust emission potential for the Hami Basin during the late Pleistocene. [ABSTRACT FROM AUTHOR]

Dust plays an important role in climate, and while our current representation of dust production includes shifts in vegetation, soil moisture, and ice cover, it does not account for the role of landscape evolution. Here, we use the Weather Research and Forecasting model coupled to an aerosol chemistry model to quantify the effects of arid landscape evolution on boundary layer conditions, dust production, and radiative properties in the Hami Basin, China, a dynamic stony desert in eastern Asia. Relative to today, altered surface roughness, sediment erodibility, and albedo combine to produce up to a ~44% increase in wind speeds (mean ≈ 15%), up to a ~59% increase in dust loading (mean ≈ 30%), and up to a ~4.4 W m−2 increase in downwelling radiation (mean ≈ 2.4 W m−2) over the Hami Basin. Our modeling results, along with geomorphological data for the western Gobi Desert, provide evidence that stony deserts acted as important Plio‐Pleistocene dust sources. Plain Language Summary: Dust from the breakdown of rocks and minerals plays an important role in Earth's atmosphere by absorbing or scattering incoming solar radiation, and by seeding clouds. Once deposited, iron‐rich dust can fertilize surface ocean waters and terrestrial soils for the growth of organisms, making dust important in the global carbon cycle. Because of its role in modifying Earth's climate, we must accurately understand ancient dust production. To test the hypothesis that past changes in dust production impacted climate, we altered the surface properties of the western Gobi Desert, a location that had a very different landscape thousands to millions of years ago, and simulated changes in wind and dust using a regional climate model. We found that this area would have experienced increased wind speeds by up to ~40%, increased dust loading by up to ~60%, and substantially altered incoming solar radiation in response to land surface evolution. Key Points: In arid regions, consideration of landscape evolution is necessary to accurately reconstruct dust production and regional climateWe use a regional climate model to quantify the effect of arid landscape evolution on dust production in the Hami Basin, ChinaRepresentative Plio‐Pleistocene surface conditions lead to enhanced winds and dust production in the Hami Basin relative to today [ABSTRACT FROM AUTHOR]