scholarly journals Atmospheric Transport of North African Dust‐Bearing Supermicron Freshwater Diatoms to South America: Implications for Iron Transport to the Equatorial North Atlantic Ocean

2021 ◽  
Vol 48 (5) ◽  
Author(s):  
Anne E. Barkley ◽  
Nicole E. Olson ◽  
Joseph M. Prospero ◽  
Alexandre Gatineau ◽  
Kathy Panechou ◽  
...  
Keyword(s):  
South America ◽  
Atlantic Ocean ◽  
North Atlantic ◽  
Iron Transport ◽  
North Atlantic Ocean ◽  
Atmospheric Transport ◽  
North African ◽  
African Dust ◽  
Freshwater Diatoms

Provenance of the Saharan winter dust plume and its response to climatic variability over the last 200 kyr

2020 ◽  
Author(s):  
Amy Jewell ◽  
Will Burton ◽  
Tereza Kunkelova ◽  
Anya Crocker ◽  
Ursula Röhl ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
North Africa ◽  
North Atlantic ◽  
Marine Sediment ◽  
North Atlantic Ocean ◽  
Sediment Cores ◽  
Terrigenous Material ◽  
North African ◽  
The North ◽  
The North Atlantic

<p>North Africa is very likely to warm over the coming century, but there is fundamental disagreement among climate model projections over the predicted response of rainfall to that warming. Geological records of wind-blown dust accumulating in marine sediment cores in the North Atlantic Ocean provide a way to assess the response of rainfall climate in the region to past intervals of global warmth.</p><p> </p><p>Dust is transported to the North Atlantic Ocean from North Africa via two routes, a summer (northern) route and a winter (southern) route. Virtually everything we have learnt so far from marine sediment cores about North African hydroclimate has come from drill sites located beneath the summer (northern) dust plume. Here we report (i) geochemical records (radiogenic isotope (<sup>87</sup>Sr/<sup>86</sup>Sr and e<sub>Nd</sub>) and XRF core scanning) from Ocean Drilling Project (ODP) Site 662 in the eastern equatorial Atlantic spanning the last 200,000 years and (ii) new <sup>87</sup>Sr/<sup>86</sup>Sr and e<sub>Nd</sub> data from North African dust sources. We redefine existing dust Preferential Source Areas (PSAs) into three geochemically distinct (Western, Central and Eastern) source regions. We show that ODP Site 662 is well-situated to study the palaeo-history of the previously under-studied African winter (southern) dust plume. We find that the primary source of terrigenous material to Site 662 throughout the past 200,000 years is palaeolake Megachad in the Central source region. This palaeolake basin is often described as the largest single dust source on Earth but comparatively little is known on geological timescales about its history. We show that its dust contribution to ODP Site 662 varies on orbital timescales, and that it reaches a minimum during insolation maxima, such as the last African Humid Period, coincident with lake high-stands. Large excursions in radiogenic isotope data reveal extreme variability in the relative strength of aeolian dust and distal riverine sources of terrigenous material, associated with hydroclimate change over the last 200 thousand years.</p>

scholarly journals Multidecadal Covariability of North Atlantic Sea Surface Temperature, African Dust, Sahel Rainfall, and Atlantic Hurricanes

2012 ◽  
Vol 25 (15) ◽  
pp. 5404-5415 ◽  
Author(s):  
Chunzai Wang ◽  
Shenfu Dong ◽  
Amato T. Evan ◽  
Gregory R. Foltz ◽  
Sang-Ki Lee
Keyword(s):  
Atlantic Ocean ◽  
Time Scales ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
African Dust ◽  
The North ◽  
Tropical North Atlantic ◽  
Sahel Rainfall ◽  
The North Atlantic ◽  
Atlantic Hurricanes

Abstract Most studies of African dust and North Atlantic climate have been limited to the short time period since the satellite era (1980 onward), precluding the examination of their relationship on longer time scales. Here a new dust dataset with the record extending back to the 1950s is used to show a multidecadal covariability of North Atlantic SST and aerosol, Sahel rainfall, and Atlantic hurricanes. When the North Atlantic Ocean was cold from the late 1960s to the early 1990s, the Sahel received less rainfall and the tropical North Atlantic experienced a high concentration of dust. The opposite was true when the North Atlantic Ocean was warm before the late 1960s and after the early 1990s. This suggests a novel mechanism for North Atlantic SST variability—a positive feedback between North Atlantic SST, African dust, and Sahel rainfall on multidecadal time scales. That is, a warm (cold) North Atlantic Ocean produces a wet (dry) condition in the Sahel and thus leads to low (high) concentration of dust in the tropical North Atlantic, which in turn warms (cools) the North Atlantic Ocean. An implication of this study is that coupled climate models need to be able to simulate this aerosol-related feedback in order to correctly simulate climate variability in the North Atlantic. Additionally, it is found that dust in the tropical North Atlantic varies inversely with the number of Atlantic hurricanes on multidecadal time scales because of the multidecadal variability of both direct and indirect influences of dust on vertical wind shear in the hurricane main development region.

Atmospheric transport of pollutants from North America to the North Atlantic Ocean

Nature ◽  
1984 ◽  
Vol 308 (5961) ◽  
pp. 722-724 ◽  
Author(s):  
R. C. Harriss ◽  
E. V. Browell ◽  
D. I. Sebacher ◽  
G. L. Gregory ◽  
R. R. Hinton ◽  
...  
Keyword(s):  
North America ◽  
Atlantic Ocean ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Atmospheric Transport ◽  
The North ◽  
The North Atlantic

Spatiotemporal evolution of the chlorophyll a trend in the North Atlantic Ocean

2018 ◽  
Vol 612 ◽  
pp. 1141-1148 ◽  
Author(s):  
Min Zhang ◽  
Yuanling Zhang ◽  
Qi Shu ◽  
Chang Zhao ◽  
Gang Wang ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Chlorophyll A ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Spatiotemporal Evolution ◽  
The North ◽  
The North Atlantic

On the uncertainty of future projections of Marine Heatwave events in the North Atlantic Ocean

2021 ◽  
Vol 56 (7-8) ◽  
pp. 2027-2056
Author(s):  
Sandra M. Plecha ◽  
Pedro M. M. Soares ◽  
Susana M. Silva-Fernandes ◽  
William Cabos
Keyword(s):  
Atlantic Ocean ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Future Projections ◽  
The North ◽  
The North Atlantic

Monthly satellite-derived phytoplankton pigment distribution for the North Atlantic Ocean basin

Eos ◽  
1986 ◽  
Vol 67 (44) ◽  
pp. 835 ◽  
Author(s):  
W. E. Esaias ◽  
G. C. Feldman ◽  
C. R. McClain ◽  
J. A. Elrod
Keyword(s):  
Atlantic Ocean ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Ocean Basin ◽  
Phytoplankton Pigment ◽  
The North ◽  
Pigment Distribution ◽  
The North Atlantic
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