Atmospheric Trace Element Dynamics in Snow and Ice Systems

Atmospheric trace elements are transported from source regions to cryospheric environments by a combination of long-range winds, wet and dry deposition, and scavenging by snow and ice crystals. Upon deposition, these elements become archived in snowpacks, firn layers and ice cores, yielding valuable records of natural dust fluxes, marine inputs and anthropogenic emissions. The solubility, particle size and chemical speciation of each element govern its mobility during post-depositional processes such as meltwater percolation and wind redistribution. Analysing concentration profiles and isotopic signatures within ice and snow strata reveals temporal trends in industrial pollution, volcanic eruptions and climate-driven shifts in source strength. These records underpin reconstructions of past atmospheric composition, inform models of global biogeochemical cycles and guide contemporary mitigation strategies for air quality and water resources in polar and high-mountain regions.

Research from Nature Portfolio

Recent studies using high-resolution ice-core measurements in the French Alps have uncovered a pronounced spike in bismuth levels coincident with mid-twentieth-century military conflicts. Chemical tracers associated with coal combustion, steel and aluminium processing were augmented by a previously unrecognised source attributed to wartime alloys and munitions. The ice-core record demonstrates that military activities between 1935 and 1945 CE contributed substantially to regional heavy‐metal pollution, highlighting the value of trace‐element archives in documenting anthropogenic inputs beyond civilian industry and transport.

Atmospheric Trace Element Dynamics in Snow and Ice Systems publication trend

The graph below shows the total number of articles in atmospheric trace element dynamics in snow and ice systems across all publications each year (not limited to Nature Index journals).

Technical terms

Trace element: A chemical element present at low concentrations (typically ng g⁻¹ to µg L⁻¹) in environmental matrices, whose sources and cycling provide insights into natural and anthropogenic processes.

Enrichment factor: A ratio comparing the concentration of an element in snow or ice to a reference crustal or marine composition, used to distinguish anthropogenic inputs from natural background.

Ice core: A cylindrical section of ice drilled from a glacier or ice sheet, preserving sequential layers of snow deposition and atmospheric constituents over time.

Firn: A transitional stage between snow and glacial ice, characterised by partially compacted grains that retain air-filled pores and record annual chemical deposition.

Aerosol deposition: The process by which airborne particles settle onto surfaces, either by gravitational settling (dry deposition) or via incorporation into precipitation (wet deposition).

Meltwater percolation: The downward movement of surface meltwater through porous snow or firn layers, which can redistribute or leach soluble chemical species.

References

1. Alpine-ice record of bismuth pollution implies a major role of military use during World War II. Scientific Reports (2023).
2. Consistent histories of anthropogenic western European air pollution preserved in different Alpine ice cores. The Cryosphere (2023).
3. Impact and implications of meltwater percolation on trace element records observed in a high-Alpine ice core. Journal of Glaciology (2018).