Origins of atmospheric particulate matter over the North Sea and the Atlantic Ocean

Losno, R.; Bergametti, Gilles; Carlier, P.

doi:10.1007/bf00115403

Cited by 28 publications

(19 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Coarse phosphorus, an element emitted during plant guttation and transpiration [ Artaxo and Hansson , 1995], accounted for less than 1% of the dust mass (coarse P/Al = 0.007 (Table 4); dust mass = Al/0.0813 [ Mason , 1966]). The SHADE P/Al ratio is consistent with the value of 0.0086 measured by Losno et al [1992]. These facts suggest that organic material is minimal in Saharan dust.…”

Section: Resultssupporting

confidence: 87%

Chemical composition of mineral dust aerosol during the Saharan Dust Experiment (SHADE) airborne campaign in the Cape Verde region, September 2000

Formenti¹

2003

J. Geophys. Res.

172

158

View full text Add to dashboard Cite

[1] During the Saharan Dust Experiment (SHADE) in September 2000, we collected filter samples on board the Met Office C-130 aircraft. The main study area was over the Atlantic Ocean between Sal Island and Senegal. Dust was encountered in the altitude range from 0.5-1 to 4-4.5 km. Sublayers with different particle size distributions and different source areas can be distinguished within the main dust plume. Diminution of O 3 in anticorrelation with the dust layer suggests removal of O 3 by dust particles. Dust loadings containing up to 54 mg m À3 Al (submicron plus supermicron fraction) were measured during particularly intense dust events. Mixing of dust with anthropogenic aerosols, mainly NH 4 HSO 4 , was observed in the fine fraction. It was associated with air masses that had originated over Europe and then traveled over North Africa. The ratio of nitrate to non-sea-salt sulfate was around 0.3. This argues against any significant influence of biomass burning emissions, which have much higher nitrate. However, we also encountered aged fossil fuel pollution plumes, likely from North America. The geochemical signature of mineral dust was consistent with previous results in the area. Si, Fe, and Ti were not enriched with respect to the soil composition, while other elements, such as Ca and S, were. Ca is prevalently present as calcite in African soils, but it is also found as calcium sulfate in the atmosphere.

show abstract

Section: Resultssupporting

confidence: 87%

Chemical composition of mineral dust aerosol during the Saharan Dust Experiment (SHADE) airborne campaign in the Cape Verde region, September 2000

Formenti¹

2003

J. Geophys. Res.

172

158

View full text Add to dashboard Cite

show abstract

“…Finally, Miami and Barbados are not strongly affected by biomass burning during the summer when most of the samples were taken. In some other regions, such as sub-Saharan Africa, the relationship between dust and TP may be masked by high levels of biomass burning and lower levels of dust [Baker et al, 2006b;Losno et al, 1992]. The biomass burning samples at our sites provided much less TP (169 AE 142 pmol m À3 ) than the dust days (651 AE 249 pmol m À3 ).…”

Section: Resultsmentioning

confidence: 79%

Atmospheric P deposition to the subtropical North Atlantic: sources, properties, and relationship to N deposition

et al. 2013

View full text Add to dashboard Cite

[1] Biogeochemical studies show that the surface waters of the subtropical North Atlantic are highly phosphorus (P) stressed. Human activity may exacerbate phosphorus stress by enhancing atmospheric nitrogen (N) deposition and raising N/P ratios in deposition. However, the magnitude of this effect is unclear, in part, because atmospherically deposited phosphorus sources are not well known, particularly the contribution from organic phosphorus. Here we report measurements of phosphorus in aerosols and wet deposition at Miami and Barbados. African dust is the major aerosol P source at both Miami and Barbados, containing~880 ppm total phosphorus and~70 ppm soluble reactive phosphorus (SRP). Organic compounds contribute, on average, 28%-44% of soluble phosphorus in precipitation. Because of dust transport seasonality, phosphorus inputs to the North Atlantic are expected to be highly variable with 2-10 times more P deposition during summer than winter. Pollution is also an important contributor to total and soluble phosphorus in Miami aerosols and deposition. Estimated SRP deposition in Barbados and Miami is 0.21 and 0.13 mmol m À2 d À1 phosphorus, respectively. Inorganic nitrogen in excess of Redfield ratio expectations in deposition was very different between the sites, totaling 21-30 and 127-132 mmol m À2 d À1 nitrogen in Barbados and Miami, respectively; the high deposition rates at Miami are linked to pollutants. Including soluble organic nitrogen and phosphorus halved the estimates of excess nitrogen in Barbados wet deposition. Thus, the organic phosphorus fraction is important in the assessment of the magnitude of biogeochemical change of the North Atlantic caused by atmospheric deposition.Citation: Zamora, L. M., J. M. Prospero, D. A. Hansell, and J. M. Trapp (2013), Atmospheric P deposition to the subtropical North Atlantic: sources, properties, and relationship to N deposition,

show abstract

“…Our median trace metal concentration data (Tables and ) and their ranges (Figure ) are consistent with previous ship‐board studies in the Atlantic, although there is a high degree of variability in observed trace metal concentrations in all of these data. For example, total and soluble Fe concentrations have been reported in the range 1.4–134,000 pmol m −3 [ Völkening and Heumann , ; Losno et al ., ; Rädlein and Heumann , , ; Johansen et al ., ; Chen and Siefert , ; Baker et al ., ; Buck et al ., ] and <2.0–775 pmol m −3 [ Johansen et al ., ; Chen and Siefert , ; Baker et al ., ; Buck et al ., ], respectively. In Tables S6 and S7, we list examples of, respectively, total and soluble aerosol trace metal concentrations previously reported for our five deposition regions.…”

Section: Resultsmentioning

confidence: 99%

Estimation of atmospheric nutrient inputs to the Atlantic Ocean from 50°N to 50°S based on large‐scale field sampling: Iron and other dust‐associated elements

Baker

Adams

Bell

et al. 2013

Global Biogeochemical Cycles

103

110

View full text Add to dashboard Cite

[1] Atmospheric inputs of mineral dust supply iron and other trace metals to the remote ocean and can influence the marine carbon cycle due to iron's role as a potentially limiting micronutrient. Dust generation, transport, and deposition are highly heterogeneous, and there are very few remote marine locations where dust concentrations and chemistry (e.g., iron solubility) are routinely monitored. Here we use aerosol and rainwater samples collected during 10 large-scale research cruises to estimate the atmospheric input of iron, aluminum, and manganese to four broad regions of the Atlantic Ocean over two 3 month periods for the years 2001-2005. We estimate total inputs of these metals to our study regions to be 4.2, 17, and 0.27 Gmol in April-June and 4.9, 14, and 0.19 Gmol in September-November, respectively. Inputs were highest in regions of high rainfall (the intertropical convergence zone and South Atlantic storm track), and rainfall contributed higher proportions of total input to wetter regions. By combining input estimates for total and soluble metals for these time periods, we calculated overall percentage solubilities for each metal that account for the contributions from both wet and dry depositions and the relative contributions from different aerosol types. Calculated solubilities were in the range 2.4%-9.1% for iron, 6.1%-15% for aluminum, and 54%-73% for manganese. We discuss sources of uncertainty in our estimates and compare our results to some recent estimates of atmospheric iron input to the Atlantic.

show abstract

Origins of atmospheric particulate matter over the North Sea and the Atlantic Ocean

Cited by 28 publications

References 30 publications

Chemical composition of mineral dust aerosol during the Saharan Dust Experiment (SHADE) airborne campaign in the Cape Verde region, September 2000

Chemical composition of mineral dust aerosol during the Saharan Dust Experiment (SHADE) airborne campaign in the Cape Verde region, September 2000

Atmospheric P deposition to the subtropical North Atlantic: sources, properties, and relationship to N deposition

Estimation of atmospheric nutrient inputs to the Atlantic Ocean from 50°N to 50°S based on large‐scale field sampling: Iron and other dust‐associated elements

Contact Info

Product

Resources

About