{"id":167851,"date":"2025-12-04T14:26:17","date_gmt":"2025-12-04T14:26:17","guid":{"rendered":"https:\/\/www.newsbeep.com\/il\/167851\/"},"modified":"2025-12-04T14:26:17","modified_gmt":"2025-12-04T14:26:17","slug":"unm-study-reveals-southwest-deserts-produce-more-dust-in-warm-periods-bucking-global-trends","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/il\/167851\/","title":{"rendered":"UNM study reveals Southwest deserts produce more dust in warm periods, bucking global trends"},"content":{"rendered":"

A new study led by The University of New Mexico researchers has uncovered a surprising pattern in how deserts of the southwestern United States produce dust over long climate cycles. Unlike most of the world\u2014where dust emissions peak during cold, glacial periods\u2014the region\u2019s deserts become dustier during warm, interglacial climates, according to findings published in Nature Communications.<\/a><\/p>\n

The research was led by Spencer Staley, a former UNM Ph.D. student and now assistant research professor at the Desert Research Institute,\u00a0with co-authors UNM Professor Peter Fawcett, R. Scott Anderson (Northern Arizona University), and Matthew Kirby (California State University, Fullerton).<\/p>\n

\"View<\/p>\n

View of Stoneman Lake in the early morning with drill rig in place.<\/p>\n

Globally, ice ages tend to be associated with sweeping, dusty landscapes. But in the deserts of Arizona, California, and Nevada, Staley and his colleagues found the opposite pattern. By analyzing a 230,000-year record of dust preserved in sediments at Stoneman Lake, Arizona, the team discovered dust emissions surged during warm, dry interglacial periods\u2014times when global dust typically declines.<\/p>\n

\u201cDeserts in southwestern North America respond very differently to longer-term climate changes compared to other major global dust sources,\u201d Staley said. \u201cEven though this region produces less dust than Northern Africa, the Middle East, and Central Asia, it is important to know how this region fits into the global picture. Our ability to predict and prepare for downwind impacts depends on it.\u201d<\/p>\n

The study is the first to continuously trace dust blown out of southwestern North America across multiple glacial\u2013interglacial cycles.<\/p>\n

Although dust is often viewed as a sign of increasing aridity, the team\u2019s findings show the story is more complex. Dust emissions in the Southwest spike right after major wet-to-dry climate transitions, when ecosystems and landscapes are shifting rapidly.<\/p>\n

\u201cOnce we realized what an incredible record of atmospheric dust deposition the Stoneman Lake core was, I expected that this record would look a lot like dust records in other parts of the world especially those from ocean sediments and polar ice cores. But the answer turned out to be much more interesting than that,\u201d explained Fawcett.<\/p>\n

\"Core<\/p>\n

Core sampling March 2020 at Northern Arizona University.<\/p>\n

As the climate warms and dries, natural disturbances such as vegetation shifts, more frequent wildfires, and intense rainfall events can erode previously stable hillslope soils. Those sediments then wash downslope and accumulate in dust-prone environments such as alluvial fans, playa lakebeds, and river floodplains.<\/p>\n

\u201cIn the long term, it doesn\u2019t matter how dry it gets if there isn\u2019t any fine sediment left to blow away,\u201d explained Staley. \u201cWhile aridity certainly plays a role in dust emissions, the more fundamental connection is to landscape disturbance.\u201d<\/p>\n

\"STL_2023-07-25_group4\"<\/p>\n

Group shot of researchers. Spencer Staley (second from the left), Peter Fawcett (3rd from left), and Scott Anderson (4th from the left).<\/p>\n

The team\u2019s insights come from an unusual source: a sediment core drilled from Stoneman Lake, a small sinkhole lake on the southwestern edge of the Colorado Plateau. Formed roughly 1.3 million years ago, the lake has quietly accumulated fine material, including dust blowing in from hundreds of miles upwind, for hundreds of thousands of years.<\/p>\n

Stoneman Lake is one of the few places in the region capable of preserving an unbroken record of sediment deposition across multiple climate cycles. Using laser particle size analysis and end-member modeling, the researchers identified distinct populations of airborne dust within the lake sediments and reconstructed how dust fluxes changed over time.<\/p>\n

\u201cWe were able to obtain a deep sediment core from Stoneman Lake because of the prolonged drought in the Southwest in the 2010\u2019s,\u201d said Fawcett. \u201cIt would have been impossible to drill down 80 meters from a small boat, but with the lake drying out completely, we were able to drive a drill rig out to the middle of the basin.\u201d<\/p>\n

\"SLT_14<\/p>\n

Recovery operations of the STL-14 core from Stoneman Lake in October 2014. A truckmounted sonic coring apparatus was driven out into the relatively dry lakebed. The early 21st century drought made this possible.<\/p>\n

\u201cStoneman Lake is really quite special. Contributions of locally eroded sediment to the lake are quite small and distinct from dust, allowing us more easily quantify airborne inputs,\u201d said Staley. \u00a0<\/p>\n

The study highlights how sediment moves through interconnected desert landscapes. Hillslopes generate fine-grained material through weathering and dust accumulation. Floodplains, rivers, playas, and alluvial fans then store and emit this sediment into the atmosphere, sometimes for thousands of years.<\/p>\n

Dust, in turn, influences cloud formation, atmospheric reflectivity, and nutrient delivery to ecosystems. Understanding how dust loads have changed in the past helps researchers improve climate models for the future.<\/p>\n

Today, human activities including agriculture, off-road vehicle use, construction, and land-clearing play an outsized role in disturbing sediment supplies. Combined with ongoing climate change, the researchers warn that modern landscapes may be pushed into even greater states of instability.<\/p>\n

\u201cWe found that increased dust emissions can persist for thousands of years when the landscape is disturbed,\u201d Staley said. \u201cWith continued warming and drying, we risk displacing the vegetation that protects remaining stores of hillslope sediment from erosion\u2014potentially increasing dust loads across the region.\u201d<\/p>\n

\"Quartz<\/p>\n

Quartz where it \u201cshouldn\u2019t\u201d be. Looking at lake sediments under a petrographic microscope, Staley kept finding quartz grains. The lake\u2019s watershed is completely underlain by basalt, a rock type that does not contain this mineral. This particular grain is rounded and pockmarked, suggesting it rumbled and tumbled its way into the lake by wind.<\/p>\n

The full study, \u201cHigher interglacial dust fluxes relative to glacial periods in southwestern North American deserts,\u201d<\/a> is available in Nature Communications.<\/p>\n

Staley and Fawcett conclude by stating that this research is relevant right here in New Mexico, explaining that the research discovered can have a similar relationship between dust, vegetation and climate.<\/p>\n

\u201cThe findings at Stoneman Lake has renewed our interest in studying another long lake sediment record from the Valles Caldera in northern New Mexico that goes back further in time than the Stoneman Lake study,\u201d said Fawcett. \u00a0<\/p>\n

A current undergraduate student in the EPS department, Elias Draven, is working with Fawcett on a similar grain size study across glacial-interglacial climates to see if the opposite dust pattern holds here as well.<\/p>\n

\u201cDust-prone features like those contributing to our record are found all across New Mexico. Therefore, we can expect similar relationships between dust emissions and landscape change here. Even so, our team is undertaking further research to study the behavior of dust sources across the state,\u201d concluded Staley. \u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"A new study led by The University of New Mexico researchers has uncovered a surprising pattern in how…\n","protected":false},"author":2,"featured_media":167852,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[85,46,141,68790,68791],"class_list":["post-167851","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-il","tag-israel","tag-science","tag-unm-department-of-earth-and-planetary-sciences","tag-unm-earth-and-planetary-sciences"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/167851","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=167851"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/167851\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/167852"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=167851"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=167851"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=167851"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}