Impact of Saharan dust on ecosystems
Initial situation and question
In the area of the Hoher Sonnblick there is a snow chemistry time series going back to the early 1980s, where the chemical composition of the snow cover is analyzed annually at the end of the accumulation period on the glacier. Almost every year there are layers with increased calcium concentrations and an increased pH value, which are attributed to the entry of mineral dust from long-distance transport (Saharan dust). It is known from the Amazon region and the Atlantic that this Saharan dust brings essential nutrients into the corresponding ecosystems and has a clear buffering effect against "acid inputs" such as sulfate and nitrate (of classic anthropogenic origin from SO2 and NOx). An open question is to what extent the deposition of Saharan dust really has a significant impact on the ecosystem on the glacier and on the meltwater. This is always postulated, although we don't actually know it exactly. The fact is, however, that the Saharan dust accounts for a not inconsiderable proportion of the total deposition in individual years.