Present-Day Patagonian Dust Emissions: Combining Surface Visibility, Mass Flux, and Reanalysis Data
The magnitude of the climatic forcing associated with mineral dust aerosols remains uncertain due in part to a lack of observations on dust sources. While modeling and satellite studies provide spatially extensive constraints, they must be supported by surface-validating dust monitoring. Southern So...
| Published in: | Journal of Geophysical Research: Atmospheres |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
AMER GEOPHYSICAL UNION
2024
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| Subjects: | |
| Online Access: | https://repositorio.uc.cl/handle/11534/78943 https://doi.org/10.1029/2020JD034459 |
| Summary: | The magnitude of the climatic forcing associated with mineral dust aerosols remains uncertain due in part to a lack of observations on dust sources. While modeling and satellite studies provide spatially extensive constraints, they must be supported by surface-validating dust monitoring. Southern South America is the main dust source to the southern oceans (>45 degrees S), a region of low biological productivity potentially susceptible to increased micronutrient fertilization through dust deposition, as well as one of the main dust sources to Antarctica, implying long-range transport of dust from Patagonia and potentially affecting snow cover albedo. We present multiyear time series of dust-related visibility reduction (DRVR) and dust mass flux in Patagonia. We find that local DRVR is partly controlled by long-term (i.e., months) water deficit, while same-day conditions play a smaller role, reflective of water retention properties of fine-grained dust-emitting soils in low-moisture conditions. This is supported independently by reanalysis data showing that large-scale dust outbreaks are usually associated with anomalously high long-term water deficit. By combining visibility data, surface dust sampling, and particle dispersion modeling, we derive regional dust emission rates. Our results suggest that the inclusion of long-term soil hydrologic balance parameterizations under low-moisture conditions may improve the performance of dust emission schemes in Earth system models. Agencia Nacional de Promocion Cientifica y Tecnologica (ANPyCT) ANID-Fondo Nacional de Desarrollo Cientifico y Tecnologico (FONDECYT) ANID/Fondecyt ANID/Fondo de Financiamiento de Centros de Investigacion en areas Prioritarias (FONDAP) ANID/Millennium Science Initiative/Millennium Nucleus Paleoclimate |
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