Improved constraints on hematite refractive index for estimating climatic effects of dust aerosols

Uncertainty in desert dust composition poses a big challenge to understanding Earth’s climate across different epochs. Of particular concern is hematite, an iron-oxide mineral dominating the solar absorption by dust particles, for which current estimates of absorption capacity vary by over two order...

Descripción completa

Detalles Bibliográficos
Autores: Li, Longlei, Mahowald, Natalie, Gonçalves Ageitos, María|||0000-0003-3857-6403, Obiso, Vincenzo, Miller, Ron, Pérez García-Pando, Carlos|||0000-0002-4456-0697, di Biagio, C, Formenti, Paola, Brodrick, Philip G, Clark, Roger Nelson, Green, Robert, Kokaly, Raymond F., Swayze, Gregg, Thompson, David R.
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/410005
Acceso en línea:https://hdl.handle.net/2117/410005
https://dx.doi.org/10.1038/s43247-024-01441-4
Access Level:acceso abierto
Palabra clave:Aerosols
Climatic changes
Mineral dusts
Canvis climàtics
Pols minerals
Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Degradació ambiental::Canvi climàtic
Àrees temàtiques de la UPC::Enginyeria civil::Geologia::Mineralogia
Descripción
Sumario:Uncertainty in desert dust composition poses a big challenge to understanding Earth’s climate across different epochs. Of particular concern is hematite, an iron-oxide mineral dominating the solar absorption by dust particles, for which current estimates of absorption capacity vary by over two orders of magnitude. Here, we show that laboratory measurements of dust composition, absorption, and scattering provide valuable constraints on the absorption potential of hematite, substantially narrowing its range of plausible values. The success of this constraint is supported by results from an atmospheric transport model compared with station-based measurements. Additionally, we identify substantial bias in simulating hematite abundance in dust aerosols with current soil mineralogy descriptions, underscoring the necessity for improved data sources. Encouragingly, the next-generation imaging spectroscopy remote sensing data hold promise for capturing the spatial variability of hematite. These insights have implications for enhancing dust modeling, thus contributing to efforts in climate change mitigation and adaptation.