A 2000 Year Saharan Dust Event Proxy Record from an Ice Core in the European Alps

Abstract

Dust events originating from the Saharan desert have far‐reaching environmental impacts, but the causal mechanism of magnitude and occurrence of Saharan dust events (SDEs) during the preinstrumental era requires further research, particularly as a potential analog for future climate. Using an ultrahigh resolution glacio‐chemical record from the 2013 Colle Gnifetti ice core drilled in the Swiss‐Italian Alps, we reconstructed a 2000‐year‐long summer Saharan dust record. We analyzed both modern (1780–2006) and premodern Common Era (CE) major and trace element records to determine air mass source regions to the Colle Gnifetti glacier and assess similarities to modern and reconstructed climate trends in the Northern Hemisphere. This new proxy SDE reconstruction, produced using measurements from a novel, continuous ultrahigh‐resolution (120‐μm) ice core analysis method (laser ablation‐inductively coupled plasma‐mass spectrometer) is comprised of 316,000 data points per element covering the period 1–1820 CE. We found that the Colle Gnifetti ice core captures an anomalous increase in Saharan dust transport during the onset of the Medieval Climate Anomaly (870–1000 CE) and records other prominent shorter events (CE, 140–170, 370–450, 1320–1370, and 1910–2000), offering a framework for new insights into the implications of Saharan dust variability.

The Pedosphere as a Sink, Source, and Record of Anthropogenic and Natural Arsenic Atmospheric Deposition

“…It is not known for any given soil whether biovolatilization is a net loss or gain, as the appropriate experiments have not been conducted. Paleodust ombrotrophic chronologies from a range of locations remote from volcanic activity, or from desert dust storm impact, all suggest that tephra and desert dust, along with charcoal indications of fire related deposition inputs, are limited, and that the bulk of dust deposited to bogs is of local or continental general soil origin. − , Enhanced dust inputs tend to be observed from the early Anthropocene, where land was cleared for agriculture, and continued to more recent agricultural expansions such as in the USA . For raised bogs, natural variation in topology and rate of bog accumulation lead to different densities of mineral dust in bog profiles, but climatic variation also has an impact .…”

Adjusting for Desert-Dust-Related Biases in a Climate Data Record of Sea Surface Temperature

“…These data are monthly averaged on a grid of 0.5 • latitude by 0.625 • longitude. To use the monthly column integrated dust mass, M, as a predictor for HadSST4 versus CCI analysis differences, the MERRA-2 data were resampled to 0.5 • by 0.5 • using the Python module, xarray (v0.15.1) [23].…”

The role of soils in the regulation of air quality

“…[81] noted low confidence in projecting future dust storm changes, due to difficulties in projecting future land use. However, dust storm activity is likely to increase where already dry regions will be prone to increased drought [12,82,83]. Climate change effects may not only increase dust emissions, but also reactivate areas prone to wind erosion [12].…”