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Please clickhereto download the map associated with this article. The Chihuahuan Desert of central northern Mexico and southern Arizona, New Mexico and Texas, USA, is a regionally significant dust ‘hot-spot’ in North America. Typical of other such hot-spots, this desert consists of a mosaic of geomorphological settings, each of which has a varying propensity for dust emission. Recently, a classification system of dust emission potential based on surface geomorphic characteristics that establishes a common framework for describing the land surface has been proposed. The classification is readily applicable to different dust source regions and designed to facilitate comparison of the relative potential dust contributions and emissivity of varying geomorphological environments in such regions. The map here (1:3,500,000) was compiled by applying the new classification to a base map of polygons from existing soil and landform maps that were produced by national government agencies. Within the study area, 11 of the 17 possible geomorphic classes were present, the most extensive being unarmoured, unincised high relief alluvial surfaces, which covered 43% of the area. As an example of how empirical dust source point data can be used with the classification, the satellite observed origins of dust plumes for 26 major wind erosion events from 2001 to 2009 were overlain on the map. Despite a total area of only 4%, ephemeral lakes were the source of 48% of the observed plumes. This map and the relationships derived from it provide the basis for developing equivalent maps in other dusty regions, and mark a step toward improving the representation and documentation of the strength of dust sources in numerical mineral aerosol models. [ABSTRACT FROM PUBLISHER]

Dust sources have been revealed through remote sensing, first regionally by ~1° resolution sensors (TOMS), then at sub-basin scale by moderate-resolution sensors (MODIS). Sensors with higher spatial resolution until recently were poorly temporally-resolved, precluding their use for systematic investigations of sources. Now, "CubeSat" constellations with high-temporal-and-spatial-resolution sensors such as PlanetScope offer ~3 m resolution and daily (to sub-daily) temporal resolution. We illustrate the spatio-temporal dust plume observation capabilities of CubeSat data through a dust event case study, Bolson de los Muertos playa, Chihuahuan Desert, Mexico. For the event, PlanetScope showed numerous discrete point sources, revealing variability of surface erodibility and emission over ~8% of a focus area at time of capture. The unprecedented detail of PlanetScope imagery revealed plume development where outer-playa sands and fluvial-deltaic inputs contact lacustrine silts/clays, consistent with field-studies. PlanetScope's high fidelity improves spatial quantification and temporal constraint of source activity, and we assess the spatio-temporal capabilities of CubeSat in context with other dust observation remote sensing systems. Compared to previous satellite technologies, CubeSats bring better potential to link remote sensing to field observations of emission. This leap forward in the remote sensing of dust sources calls for the systematic analysis of CubeSat imagery in source areas. Image 1 • Remote sensing has enabled key characterisations of mineral dust sources globally. • Moderate-resolution sensors cannot be reconciled with field study of dust emission. • New CubeSat technology allows observation of active emission processes. • Potential for sub-daily source monitoring from sensors in constellations. • We call for the systematic application of CubeSat imagery over dust sources. [ABSTRACT FROM AUTHOR]