Saharan Dust Transport and High-Latitude Glacial Climatic Variability: The Alboran Sea Record

Abstract

Millennial to submillennial marine oscillations that are linked with the North Atlantic's Heinrich events and Dansgaard–Oeschger cycles have been reported recently from the Alboran Sea, revealing a close ocean-atmosphere coupling in the Mediterranean region. We present a high-resolution record of lithogenic fraction variability along IMAGES Core MD 95-2043 from the Alboran Sea that we use to infer fluctuations of fluvial and eolian inputs to the core site during periods of rapid climate change, between 28,000 and 48,000 cal yr B.P. Comparison with geochemical and pollen records from the same core enables end-member compositions to be determined and to document fluctuations of fluvial and eolian inputs on millennial and faster timescales. Our data document increases in northward Saharan dust transports during periods of strengthened atmospheric circulation in high northern latitudes. From this we derive two atmospheric scenarios which are linked with the intensity of meridional atmospheric pressure gradients in the North Atlantic region.

Fungal microbiota from rain water and pathogenicity of Fusarium species isolated from atmospheric dust and rainfall dust

“…Previous studies revealed the presence of five different Fusarium species in the river and sea water of southeastern Spain [23]. Fluvial sediments transport was proposed as the primary route for the transportation of lithogenic and fungal particulates to the Alboran Sea [20,24]. The results presented here allow us to speculate on a new source of inoculum for Fusarium genus: atmospheric dust, which can fall down directly or together with rain.…”

Geomorphological investigations of sediment traps on Lanzarote (Canary Islands) as a key for the interpretation of a palaeoclimate archive off NW Africa

“…Furthermore, palaeoenvironmental research indicates that stable conditions in the northwest African area over a time span of more than 10 ka would not be expected. Thus, a strong influence of climatic cycles like Heinrich-events and D-O cycles occurring with a high frequency of some ka on this region is reported from several studies (Cacho et al, 1999;Moreno et al, 2002, Moreno andCanals 2004), which play an important role in this geomorphic environment instable even during generally wetter periods. Furthermore, high electric conductivity of the sediments (e.g.…”

Controls on carbonate and terrigenous deposition in the incipient Benguela upwelling system during the middle to the late Miocene (ODP Sites 1085 and 1087)

“…Close to the continent, the sediments are generally coarser grained compared with the distal open ocean. Most deep-sea cores recovered within hundreds of kilometers off continents are characterized by fine-grained aeolian dust (2-4 μm; e.g., Boven and Rea, 1998;Rea and Hovan, 1995), while several deep- sea sediment studies located relatively close to the continent showed that aeolian dust fallout is characterized by terrigenous sediment with a modal grain size larger than 6 μm (e.g., Koopmann, 1981;Holz et al, 2004;Moreno et al, 2002;Stuut et al, 2002). This is supported by the coarse silt sized of present-day dust samples from the Namib Desert collected along transect from the coast to the core Site at MD 962094, Walvis Ridge (Stuut et al, 2002).…”