Journal articles: 'Patagonian dust'

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Ackert Jr, Robert P. "Patagonian dust machine." Nature Geoscience 2, no. 4 (April 2009): 244–45. http://dx.doi.org/10.1038/ngeo485.

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Johnson, M. S., N. Meskhidze, V. P. Kiliyanpilakkil, and S. Gassó. "Understanding the transport of Patagonian dust and its influence on marine biological activity in the South Atlantic Ocean." Atmospheric Chemistry and Physics Discussions 10, no. 11 (November 10, 2010): 27283–320. http://dx.doi.org/10.5194/acpd-10-27283-2010.

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Abstract. The supply of bioavailable iron to the high-nitrate low-chlorophyll (HNLC) waters of the Southern Ocean through atmospheric pathways could stimulate phytoplankton blooms and have major implications for the global carbon cycle. In this study, model results and remotely-sensed data are analyzed to examine the horizontal and vertical transport pathways of Patagonian dust and quantify the effect of iron-laden mineral dust deposition on marine biological productivity in the surface waters of the South Atlantic Ocean (SAO). Model simulations for the atmospheric transport and deposition of mineral dust and bioavailable iron are carried out for two large dust outbreaks originated at the source regions of Northern Patagonia during the austral summer of 2009. Model-simulated horizontal and vertical transport pathways of Patagonian dust plumes are in reasonable agreement with remotely-sensed data. Simulations indicate that the synoptic meteorological patterns of high and low pressure systems are largely accountable for dust transport trajectories over the SAO. According to model results and retrievals from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), synoptic flows caused by opposing pressure systems (a high pressure system located to the east or north-east of a low pressure system) elevate the South American dust plumes well above the marine boundary layer. Under such conditions, the bulk concentration of mineral dust can quickly be transported around the low pressure system in a clockwise manner, follow the southeasterly advection pathway, and reach the HNLC waters of the SAO and Antarctica in ~3–4 days after emission from the source regions of Northern Patagonia. Two different mechanisms for dust-iron mobilization into a bioavailable form are considered in this study. A global 3-D chemical transport model (GEOS-Chem), implemented with an iron dissolution scheme, is employed to estimate the atmospheric fluxes of soluble iron, while a dust/biota assessment tool (Boyd et al., 2010) is applied to evaluate the amount of bioavailable iron formed through the slow and sustained leaching of dust in the ocean mixed layer. The effect of iron-laden mineral dust supply on surface ocean biomass is investigated by comparing predicted surface chlorophyll-a concentration ([Chl-a]) to remotely-sensed data. As the dust transport episodes examined here represent large summertime outflows of mineral dust from South American continental sources, this study suggests that (1) atmospheric fluxes of mineral dust from Patagonia are not likely to be the major source of bioavailable iron to ocean regions characterized by high primary productivity; (2) even if Patagonian dust plumes may not cause visible algae blooms, they could still influence background [Chl-a] in the South Atlantic sector of the Southern Ocean.

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Johnson, M. S., N. Meskhidze, V. P. Kiliyanpilakkil, and S. Gassó. "Understanding the transport of Patagonian dust and its influence on marine biological activity in the South Atlantic Ocean." Atmospheric Chemistry and Physics 11, no. 6 (March 17, 2011): 2487–502. http://dx.doi.org/10.5194/acp-11-2487-2011.

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Abstract. The supply of bioavailable iron to the high-nitrate low-chlorophyll (HNLC) waters of the Southern Ocean through atmospheric pathways could stimulate phytoplankton blooms and have major implications for the global carbon cycle. In this study, model results and remotely-sensed data are analyzed to examine the horizontal and vertical transport pathways of Patagonian dust and quantify the effect of iron-laden mineral dust deposition on marine biological productivity in the surface waters of the South Atlantic Ocean (SAO). Model simulations for the atmospheric transport and deposition of mineral dust and bioavailable iron are carried out for two large dust outbreaks originated at the source regions of northern Patagonia during the austral summer of 2009. Model-simulated horizontal and vertical transport pathways of Patagonian dust plumes are in reasonable agreement with remotely-sensed data. Simulations indicate that the synoptic meteorological patterns of high and low pressure systems are largely accountable for dust transport trajectories over the SAO. According to model results and retrievals from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), synoptic flows caused by opposing pressure systems (a high pressure system located to the east or north-east of a low pressure system) elevate the South American dust plumes well above the marine boundary layer. Under such conditions, the bulk concentration of mineral dust can quickly be transported around the low pressure system in a clockwise manner, follow the southeasterly advection pathway, and reach the HNLC waters of the SAO and Antarctica in ~3–4 days after emission from the source regions of northern Patagonia. Two different mechanisms for dust-iron mobilization into a bioavailable form are considered in this study. A global 3-D chemical transport model (GEOS-Chem), implemented with an iron dissolution scheme, is employed to estimate the atmospheric fluxes of soluble iron, while a dust/biota assessment tool (Boyd et al., 2010) is applied to evaluate the amount of bioavailable iron formed through the slow and sustained leaching of dust in the ocean mixed layer. The effect of iron-laden mineral dust supply on surface ocean biomass is investigated by comparing predicted surface chlorophyll-a concentration ([Chl-a]) to remotely-sensed data. As the dust transport episodes examined here represent large summertime outflows of mineral dust from South American continental sources, this study suggests that (1) atmospheric fluxes of mineral dust from Patagonia are not likely to be the major source of bioavailable iron to ocean regions characterized by high primary productivity; (2) even if Patagonian dust plumes may not cause visible algae blooms, they could still influence background [Chl-a] in the South Atlantic sector of the Southern Ocean.

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Iriondo, Martin. "Patagonian dust in Antarctica." Quaternary International 68-71 (June 2000): 83–86. http://dx.doi.org/10.1016/s1040-6182(00)00035-5.

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Castagna, A., H. Evangelista, L. G. Tilstra, and R. Kerr. "Emissions from potential Patagonian dust sources and associated biological response in the Atlantic sector of the Southern Ocean." Biogeosciences Discussions 11, no. 7 (July 31, 2014): 11671–99. http://dx.doi.org/10.5194/bgd-11-11671-2014.

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Abstract. The effect of Patagonian dust over primary producers in the Southern Ocean has long been disputed. Here we present new remote sensing evidence in favour of dust mediated biological response and postulate a hypothesis to explain the spatial relation observed. A new remote sensing definition of dust source areas based on the Normalized Difference Vegetation Index (NDVI) and Absorbing Aerosol Index (AAI) correlation is presented and interannual variation in AAI is evaluated within the source regions as a proxy for dust activity. Correlation of this data with annual chlorophyll concentration, phytoplankton biomass, and diatom dominance reveals a spatially coherent latitudinal band of positive correlation concentrated between the Polar Front and the Subtropical Front. This pattern is restricted to western areas in the biomass correlation and extends toward Africa for the chlorophyll and diatom correlation. This region is equivalent to the area of the Subantarctic Mode Water formation, characterized by a ratio Si : N ≪ 1 in late summer, an unfavourable condition for diatom development, especially under iron limitation. Therefore, due to Si–Fe co-limitation, the positive correlation could be the consequence of an enhanced sensibility of this area to external iron addition for diatom growth. For the Argentinean shelf-break, is not clear whether direct dust input and/or wind stress driving water masses upwelling could be responsible for the positive correlation.

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Laluraj, C. M., M. Thamban, and K. Satheesan. "Dust and associated trace element fluxes in a firn core from the coastal East Antarctica and its linkages with the Southern Hemisphere climate variability over the last ~ 50 yr." Climate of the Past Discussions 9, no. 2 (April 5, 2013): 1841–67. http://dx.doi.org/10.5194/cpd-9-1841-2013.

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Abstract. High-resolution records of dust and trace element fluxes were studied in a firn core from the coastal Dronning Maud Land (cDML) in East Antarctica to identify the influence of climate variability on accumulation of these components over the past ~ 50 yr. A doubling of dust deposition was observed since 1985, coinciding with a shift in the Southern Annular Mode (SAM) index to positive values and associated increase in the wind speed. Back-trajectories showed that an increase in dust deposition is associated with the air parcels originating from north-west of the site, possibly indicating its origin from the Patagonian region. Our results suggest that while multiple processes could have influenced the increased dust formation, shift in SAM had a dominant influence on its transport. It is observed that since the 1985s the strength of easterlies increased significantly over the cDML region, which could sink air and dust material to the region that were brought by the westerlies through mass compensation. The correlation between the dust flux and δ18O records further suggest that enhanced dust flux in the firn core occurred during periods of colder atmospheric temperature, which reduced the moisture content and increased dust fall. Interestingly, the timing and amplitude of the insoluble dust peaks matched remarkably well with the fluxes of Ba, Cr, Cu, and Zn confirming that dust was the main carrier/source of atmospheric trace elements to East Antarctica during the recent past.

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Paparazzo, Flavio, Augusto Crespi-Abril, Rodrigo Gonçalves, Elena Barbieri, Leilén Gracia Villalobos, Miriam Solís, and Gaspar Soria. "Patagonian Dust as a Source of Macronutrients in the Southwest Atlantic Ocean." Oceanography 31, no. 4 (December 1, 2018): 33–39. http://dx.doi.org/10.5670/oceanog.2018.408.

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Sugden, David E., Robert D. McCulloch, Aloys J. M. Bory, and Andrew S. Hein. "Influence of Patagonian glaciers on Antarctic dust deposition during the last glacial period." Nature Geoscience 2, no. 4 (March 29, 2009): 281–85. http://dx.doi.org/10.1038/ngeo474.

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McCulloch, Robert. "A Patagonian glacial geomorphological mechanism for variations in dust emissions recorded in Antarctic ice cores." Quaternary International 279-280 (November 2012): 316. http://dx.doi.org/10.1016/j.quaint.2012.08.890.

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Kaiser, Jérôme, and Frank Lamy. "Links between Patagonian Ice Sheet fluctuations and Antarctic dust variability during the last glacial period (MIS 4-2)." Quaternary Science Reviews 29, no. 11-12 (June 2010): 1464–71. http://dx.doi.org/10.1016/j.quascirev.2010.03.005.

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Ulke, Ana Graciela, Marcela M. Torres Brizuela, Graciela B. Raga, and Darrel Baumgardner. "Aerosol properties and meteorological conditions in the city of Buenos Aires, Argentina, during the resuspension of volcanic ash from the Puyehue-Cordón Caulle eruption." Natural Hazards and Earth System Sciences 16, no. 9 (September 27, 2016): 2159–75. http://dx.doi.org/10.5194/nhess-16-2159-2016.

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Abstract. The eruption in June 2011 of the Puyehue-Cordón Caulle Volcanic Complex in Chile impacted air traffic around the Southern Hemisphere for several months after the initial ash emissions. The ash deposited in vast areas of the Patagonian Steppe was subjected to the strong wind conditions prevalent during the austral winter and spring experiencing resuspension over various regions of Argentina. In this study we analyze the meteorological conditions that led to the episode of volcanic ash resuspension which impacted the city of Buenos Aires and resulted in the closure of the two main airports in Buenos Aires area (Ezeiza and Aeroparque) on 16 October 2011. A relevant result is that resuspended material (volcanic ash plus dust) imprints a distinguishable feature within the atmospheric thermodynamic vertical profiles. The thermodynamic soundings show the signature of "pulses of drying" in layers associated with the presence of hygroscopic ash in the atmosphere that has already been reported in similar episodes after volcanic eruptions in other parts of the world. This particular footprint can be used to detect the probable existence of volcanic ash layers. This study also illustrates the utility of ceilometers to detect not only cloud base at airports but also volcanic ash plumes at the boundary layer and up to 7 km altitude. Aerosol properties measured in the city during the resuspension episode indicate the presence of enhanced concentrations of aerosol particles in the boundary layer along with spectral signatures in the measurements at the Buenos Aires AERONET site typical of ash plus dust advected towards the city. The mandatory aviation reports from the National Weather Service about airborne and deposited volcanic ash at the airport near the measurement site (Aeroparque) correlate in time with the enhanced concentrations. The presence of the resuspended material was detected by the CALIOP lidar overpassing the region. Since the dynamics of ash resuspension and recirculation are similar to the dynamics of dust storms, we use the HYSPLIT model with the dust storm module to simulate the episode that affected Buenos Aires. The results of the modeling agree qualitatively with satellite lidar measurements.

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Basile, Isabelle, Francis E. Grousset, Marie Revel, Jean Robert Petit, Pierre E. Biscaye, and Nartssis I. Barkov. "Patagonian origin of glacial dust deposited in East Antarctica (Vostok and Dome C) during glacial stages 2, 4 and 6." Earth and Planetary Science Letters 146, no. 3-4 (February 1997): 573–89. http://dx.doi.org/10.1016/s0012-821x(96)00255-5.

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Grigholm, B., P. A. Mayewski, A. V. Kurbatov, Gino Casassa, A. Contreras Staeding, M. Handley, S. B. Sneed, and D. S. Introne. "Chemical composition of fresh snow from Glaciar Marinelli, Tierra del Fuego, Chile." Journal of Glaciology 55, no. 193 (2009): 769–76. http://dx.doi.org/10.3189/002214309790152546.

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AbstractA fresh-snow sampling campaign was conducted during the late austral summer of 2006 in the accumulation zone of Glaciar Marinelli, located in the Cordillera Darwin, Tierra del Fuego, Chile. Snow samples were analyzed for stable isotopes (δ18O), major soluble ions (Na+, K+, Ca2+, Mg2+, Cl−, NO3−, SO42−, MS−) and major and trace elements (Na, Mg, Al, Fe, Ca, Sr, Cd, Cs, Ba, La, Ce, Pr, Dy, Ho, Er, Bi, U, As, Ti, V, Cr, Mn). The dominance of marine chemistry resembles that in studies from Patagonian glaciers. Snow chemistry was dominantly loaded by marine species (Cl−, Na+ and ssSO42−), while contributions of crustal species (e.g. Al and Fe) were very low. Empirical orthogonal function analysis suggests two possible dust sources, one represented by Al and Fe and the other by La, Ce and Pr. Enrichment-factor calculations suggest the majority of elements are within average upper-crustal ratios, but major enrichments of Bi and Cd (hundreds of times) suggest possible anthropogenic sources. Linear correlation of δ18O and barometric pressure (r = 0.60, p < 0.007) suggests a potential ‘amount effect’ relationship between depleted δ18O ratios and stronger storm conditions (e.g. greater precipitation). The snow-chemistry records from Glaciar Marinelli are the first measured in Tierra del Fuego, the southernmost glaciated region outside Antarctica.

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Haberzettl, Torsten, Flavio S. Anselmetti, Sabine W. Bowen, Michael Fey, Christoph Mayr, Bernd Zolitschka, Daniel Ariztegui, et al. "Late Pleistocene dust deposition in the Patagonian steppe - extending and refining the paleoenvironmental and tephrochronological record from Laguna Potrok Aike back to 55ka." Quaternary Science Reviews 28, no. 25-26 (December 2009): 2927–39. http://dx.doi.org/10.1016/j.quascirev.2009.07.021.

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Foth, Andreas, Thomas Kanitz, Ronny Engelmann, Holger Baars, Martin Radenz, Patric Seifert, Boris Barja, Michael Fromm, Heike Kalesse, and Albert Ansmann. "Vertical aerosol distribution in the southern hemispheric midlatitudes as observed with lidar in Punta Arenas, Chile (53.2° S and 70.9° W), during ALPACA." Atmospheric Chemistry and Physics 19, no. 9 (May 10, 2019): 6217–33. http://dx.doi.org/10.5194/acp-19-6217-2019.

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Abstract. Within this publication, lidar observations of the vertical aerosol distribution above Punta Arenas, Chile (53.2∘ S and 70.9∘ W), which have been performed with the Raman lidar PollyXT from December 2009 to April 2010, are presented. Pristine marine aerosol conditions related to the prevailing westerly circulation dominated the measurements. Lofted aerosol layers could only be observed eight times during the whole measurement period. Two case studies are presented showing long-range transport of smoke from biomass burning in Australia and regionally transported dust from the Patagonian Desert, respectively. The aerosol sources are identified by trajectory analyses with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) and FLEXible PARTicle dispersion model (FLEXPART). However, seven of the eight analysed cases with lofted layers show an aerosol optical thickness of less than 0.05. From the lidar observations, a mean planetary boundary layer (PBL) top height of 1150 ± 350 m was determined. An analysis of particle backscatter coefficients confirms that the majority of the aerosol is attributed to the PBL, while the free troposphere is characterized by a very low background aerosol concentration. The ground-based lidar observations at 532 and 1064 nm are supplemented by the Aerosol Robotic Network (AERONET) Sun photometers and the space-borne Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO). The averaged aerosol optical thickness (AOT) determined by CALIOP was 0.02 ± 0.01 in Punta Arenas from 2009 to 2010.

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Han, Changhee, Laurie J. Burn, Paul Vallelonga, Soon Do Hur, Claude F. Boutron, Yeongcheol Han, Sanghee Lee, Ahhyung Lee, and Sungmin Hong. "Lead Isotopic Constraints on the Provenance of Antarctic Dust and Atmospheric Circulation Patterns Prior to the Mid-Brunhes Event (~430 kyr ago)." Molecules 27, no. 13 (June 30, 2022): 4208. http://dx.doi.org/10.3390/molecules27134208.

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A lead (Pb) isotopic record, covering the two oldest glacial–interglacial cycles (~572 to 801 kyr ago) characterized by lukewarm interglacials in the European Project for Ice Coring in Antarctica Dome C ice core, provides evidence for dust provenance in central East Antarctic ice prior to the Mid-Brunhes Event (MBE), ~430 kyr ago. Combined with published post-MBE data, distinct isotopic compositions, coupled with isotope mixing model results, suggest Patagonia/Tierra del Fuego (TdF) as the most important sources of dust during both pre-MBE and post-MBE cold and intermediate glacial periods. During interglacials, central-western Argentina emerges as a major contributor, resulting from reduced dust supply from Patagonia/TdF after the MBE, contrasting to the persistent dominance of dust from Patagonia/TdF before the MBE. The data also show a small fraction of volcanic Pb transferred from extra-Antarctic volcanoes during post-MBE interglacials, as opposed to abundant transfer prior to the MBE. These differences are most likely attributed to the enhanced wet removal efficiency with the hydrological cycle intensified over the Southern Ocean, associated with a poleward shift of the southern westerly winds (SWW) during warmer post-MBE interglacials, and vice versa during cooler pre-MBE ones. Our results highlight sensitive responses of the SWW and the associated atmospheric conditions to stepwise Antarctic warming.

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Gassó, S., A. Stein, F. Marino, E. Castellano, R. Udisti, and J. Ceratto. "A combined observational and modeling approach to study modern dust transport from the Patagonia desert to East Antarctica." Atmospheric Chemistry and Physics Discussions 10, no. 5 (May 25, 2010): 13287–335. http://dx.doi.org/10.5194/acpd-10-13287-2010.

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Abstract. The understanding of present atmospheric transport processes from Southern Hemisphere (SH) landmasses to Antarctica can improve the interpretation of stratigraphic data in Antarctic ice cores. In addition, long range transport can deliver key nutrients normally not available to marine ecosystems in the Southern Ocean and may trigger or enhance primary productivity. However, there is a dearth of observational based studies of dust transport in the SH. This work aims to improve current understanding of dust transport in the SH by showing a characterization of two dust events originating in the Patagonia desert (south end of South America). The approach is based on a combined and complementary use of satellite retrievals (detectors MISR, MODIS, GLAS, POLDER, OMI), transport model simulation (HYSPLIT) and surface observations near the sources and aerosol measurements in Antarctica (Neumayer and Concordia sites). Satellite imagery and visibility observations confirm dust emission in a stretch of dry lakes along the coast of the Tierra del Fuego (TdF) island (~54° S) and from the shores of the Colihue Huapi lake in Central Patagonia (~46° S) in February 2005. Model simulations initialized by these observations reproduce the timing of an observed increase in dust concentration at the Concordia Station and some of the observed increases in atmospheric aerosol absorption (here used as a dust proxy) in the Neumayer station. The TdF sources were the largest contributors of dust at both sites. The transit times from TdF to the Neumayer and Concordia sites are 6–7 and 9–10 days respectively. Lidar observations and model outputs coincide in placing most of the dust cloud in the boundary layer and suggest significant deposition over the ocean immediately downwind. Boundary layer dust was detected as far as 1800 km from the source and $\\sim $800 km north of the South Georgia Island over the central sub-Antarctic Atlantic Ocean. Although the analysis suggests the presence of dust at ~1500 km SW of South Africa five days after, the limited capabilities of existing satellite platforms to differentiate between aerosol types do not permit a definitive conclusion. In addition, the model simulations show dust lifting to the free troposphere as it travels south but it could not be confirmed by the satellite observations due to cloudiness. This work demonstrates that complementary information from existing transport models, satellite and surface data can yield a consistent picture of the dust transport from the Patagonia desert to Antarctica. It also illustrates the limitation of using any of these approaches individually to characterize the transport of dust in a heavily cloudy area.

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Gassó, S., A. Stein, F. Marino, E. Castellano, R. Udisti, and J. Ceratto. "A combined observational and modeling approach to study modern dust transport from the Patagonia desert to East Antarctica." Atmospheric Chemistry and Physics 10, no. 17 (September 6, 2010): 8287–303. http://dx.doi.org/10.5194/acp-10-8287-2010.

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Abstract. The understanding of present atmospheric transport processes from Southern Hemisphere (SH) landmasses to Antarctica can improve the interpretation of stratigraphic data in Antarctic ice cores. In addition, long range transport can deliver key nutrients normally not available to marine ecosystems in the Southern Ocean and may trigger or enhance primary productivity. However, there is a dearth of observational based studies of dust transport in the SH. This work aims to improve current understanding of dust transport in the SH by showing a characterization of two dust events originating in the Patagonia desert (south end of South America). The approach is based on a combined and complementary use of satellite retrievals (detectors MISR, MODIS, GLAS, POLDER, OMI), transport model simulation (HYSPLIT) and surface observations near the sources and aerosol measurements in Antarctica (Neumayer and Concordia sites). Satellite imagery and visibility observations confirm dust emission in a stretch of dry lakes along the coast of the Tierra del Fuego (TdF) island (~54° S) and from the shores of the Colihue Huapi lake in Central Patagonia (~46° S) in February 2005. Model simulations initialized by these observations reproduce the timing of an observed increase in dust concentration at the Concordia Station and some of the observed increases in atmospheric aerosol absorption (here used as a dust proxy) in the Neumayer station. The TdF sources were the largest contributors of dust at both sites. The transit times from TdF to the Neumayer and Concordia sites are 6–7 and 9–10 days respectively. Lidar observations and model outputs coincide in placing most of the dust cloud in the boundary layer and suggest significant deposition over the ocean immediately downwind. Boundary layer dust was detected as far as 1800 km from the source and ~800 km north of the South Georgia Island over the central sub-Antarctic Atlantic Ocean. Although the analysis suggests the presence of dust at ~1500 km SW of South Africa five days after, the limited capabilities of existing satellite platforms to differentiate between aerosol types do not permit a definitive conclusion. In addition, the model simulations show dust lifting to the free troposphere as it travels south but it could not be confirmed by the satellite observations due to cloudiness. This work demonstrates that complementary information from existing transport models, satellite and surface data can yield a consistent picture of the dust transport from the Patagonia desert to Antarctica. It also illustrates the limitation of using any of these approaches individually to characterize the transport of dust in a heavily cloudy area.

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Vogt, Thea, Norbert Clauer, and Isabelle Techer. "The glaciogenic origin of the Pleistocene calcareous dust in Argentina on the basis of field, mineralogical, textural, and geochemical analyses." Quaternary Research 91, no. 1 (August 30, 2018): 218–33. http://dx.doi.org/10.1017/qua.2018.74.

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AbstractCalcareous dust occurs in Argentina as layers and pockets closely associated with Pleistocene deposits and periglacial features from southernmost Patagonia to at least the Mendoza Precordillera and has been traditionally interpreted as a soil horizon resulting from postdepositional pedogenesis during interglacials. Detailed field and microscopic observations and sedimentological and geochemical analyses of more than 100 samples collected from lower to upper Pleistocene deposits between 51°S and 33°S and from near sea level to 2800 m asl allow us to interpret the dust as synchronous with the host sediment. All observations and analyses lead us to conclude that: (1) the cryogenic morphology and the chemical signatures of the calcite component show that the dust is glaciogenic, (2) the dust was carried by southeasterly Antarctic winds, and (3) it was deposited over most of southern and central Argentina. Field observations, geomorphic evidence, and radiocarbon dates suggest that the dust was deposited during several Pleistocene glacial episodes.

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BRUSA, FRANCISCO, and CRISTINA DAMBORENEA. "Polycladida Acotylea from Patagonia. Redescription of Crassiplana albatrossi (Pseudostylochidae), lectotype designation and first record of Notocomplana palta (Notoplanidae)." Zootaxa 2903, no. 1 (June 2, 2011): 29. http://dx.doi.org/10.11646/zootaxa.2903.1.3.

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Crassiplana albatrossi is redescribed on the basis of material collected in Patagonia (Argentina) and type material deposited in the USNM. The specimens have specific characters, showing tentacles; tentacular, brain and marginal eyes; genital pores in the posterior portion; male copulatory system with penis papilla; prostatic vesicle free, with strong muscular walls; internal epithelium of prostatic vesicle glandular and with conspicuous projections; seminal vesicle present; vagina very long and extending anteriorly up to pharynx; Lang’s vesicle absent; genito-intestinal duct present. Known geographic range is increased to include Patagonia (Argentina). Identity of Notocomplana palta is confirmed based on the presence of characters in the original description including: strongly muscular seminal vesicle, long, thin and muscular ejaculatory duct stretching into prostatic vesicle, which has a high and folded epithelium; conical penis papilla. A lectotype is designated from the material studied by Marcus and housed in the SMNH. Known geographic range of Notocomplana palta, known only from the type locality in south Chile, is enlarged to include Patagonia (Argentina), revealing its Magellanic affinities.

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Anderson, Robert F., Stephen Barker, Martin Fleisher, Rainer Gersonde, Steven L. Goldstein, Gerhard Kuhn, P. Graham Mortyn, Katharina Pahnke, and Julian P. Sachs. "Biological response to millennial variability of dust and nutrient supply in the Subantarctic South Atlantic Ocean." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2019 (July 13, 2014): 20130054. http://dx.doi.org/10.1098/rsta.2013.0054.

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Fluxes of lithogenic material and fluxes of three palaeo-productivity proxies (organic carbon, biogenic opal and alkenones) over the past 100 000 years were determined using the 230 Th-normalization method in three sediment cores from the Subantarctic South Atlantic Ocean. Features in the lithogenic flux record of each core correspond to similar features in the record of dust deposition in the EPICA Dome C ice core. Biogenic fluxes correlate with lithogenic fluxes in each sediment core. Our preferred interpretation is that South American dust, most probably from Patagonia, constitutes a major source of lithogenic material in Subantarctic South Atlantic sediments, and that past biological productivity in this region responded to variability in the supply of dust, probably due to biologically available iron carried by the dust. Greater nutrient supply as well as greater nutrient utilization (stimulated by dust) contributed to Subantarctic productivity during cold periods, in contrast to the region south of the Antarctic Polar Front (APF), where reduced nutrient supply during cold periods was the principal factor limiting productivity. The anti-phased patterns of productivity on opposite sides of the APF point to shifts in the physical supply of nutrients and to dust as cofactors regulating productivity in the Southern Ocean.

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Selkin, Peter A., Caroline A. E. Strömberg, Regan Dunn, Matthew J. Kohn, Alfredo A. Carlini, K. Siân Davies-Vollum, and Richard H. Madden. "Climate, dust, and fire across the Eocene-Oligocene transition, Patagonia." Geology 43, no. 7 (July 2015): 567–70. http://dx.doi.org/10.1130/g36664.1.

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Schwanck, Franciele, Jefferson Cardia Simões, Michael Handley, Paul Andrew Mayewski, Ronaldo Torma Bernardo, and Francisco Eliseu Aquino. "Drilling, processing and first results for Mount Johns ice core in West Antarctica Ice Sheet." Brazilian Journal of Geology 46, no. 1 (March 2016): 29–40. http://dx.doi.org/10.1590/2317-4889201620150035.

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ABSTRACT: An ice core, 92.26 m in length, was collected near the ice divide of the West Antarctica ice sheet during the 2008/2009 austral summer. This paper described the fieldwork at the Mount Johns site (79º55'S; 94º23'W) and presented the first results of the upper 45.00 m record covering approximately 125 years (1883 - 2008), dated by annual layer counting and volcanic reference horizons. Trace element concentrations in 2,137 samples were determined using inductively coupled plasma mass spectrometry. The concentrations obtained for Al, Ba, Ca, Fe, K, Mg, Mn, Na, Sr and Ti are controlled by climate variations, the transport distance, and the natural sources of these aerosols. Natural dust contributions, mainly derived from the arid areas of Patagonia and Australia, are important sources for aluminum, barium, iron, manganese and titanium. Marine aerosols from sea ice and transported by air masses are important sources of sodium and magnesium. Calcium, potassium and strontium showed considerable inputs of both continental dust and marine aerosols.

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Maggi, Valter, Giovanni Baccolo, Giannantonio Cibin, Barbara Delmonte, Dariush Hampai, and Augusto Marcelli. "XANES Iron Geochemistry in the Mineral Dust of the Talos Dome Ice Core (Antarctica) and the Southern Hemisphere Potential Source Areas." Condensed Matter 3, no. 4 (December 6, 2018): 45. http://dx.doi.org/10.3390/condmat3040045.

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X-ray absorption near edge structure (XANES) measurements at the Fe K-edge were performed on aeolian dust in the TALos Dome Ice CorE drilling project (TALDICE) ice core drilled in the peripheral East Antarctic plateau, as well as on Southern Hemisphere potential source area samples. While South American sources show, as expected, a progressive increase in Fe oxidation with decreasing latitude, Antarctic sources show Fe oxidation levels higher than expected in such a cold polar environment, probably because of their very high exposure ages. Results from the TALDICE dust samples are compatible with a South American influence at the site during MIS2 (marine isotopic stage 2, the last and coldest phase of the last glacial period), in particular from Patagonia and Tierra del Fuego. However, a contribution from Australia and/or local Antarctic sources cannot be ruled out. Finally, important changes also occurred during the deglaciation and in the Holocene, when the influence of Antarctic local sources seems to have become progressively more important in recent times. This research is the first successful attempt to extract temporal climatic information from X-ray absorption spectroscopic data of the insoluble mineral dust particles contained in an ice core and shows the high potential of this technique.

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Meinander, Outi, Pavla Dagsson-Waldhauserova, Pavel Amosov, Elena Aseyeva, Cliff Atkins, Alexander Baklanov, Clarissa Baldo, et al. "Newly identified climatically and environmentally significant high-latitude dust sources." Atmospheric Chemistry and Physics 22, no. 17 (September 14, 2022): 11889–930. http://dx.doi.org/10.5194/acp-22-11889-2022.

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Abstract. Dust particles from high latitudes have a potentially large local, regional, and global significance to climate and the environment as short-lived climate forcers, air pollutants, and nutrient sources. Identifying the locations of local dust sources and their emission, transport, and deposition processes is important for understanding the multiple impacts of high-latitude dust (HLD) on the Earth's systems. Here, we identify, describe, and quantify the source intensity (SI) values, which show the potential of soil surfaces for dust emission scaled to values 0 to 1 concerning globally best productive sources, using the Global Sand and Dust Storms Source Base Map (G-SDS-SBM). This includes 64 HLD sources in our collection for the northern (Alaska, Canada, Denmark, Greenland, Iceland, Svalbard, Sweden, and Russia) and southern (Antarctica and Patagonia) high latitudes. Activity from most of these HLD sources shows seasonal character. It is estimated that high-latitude land areas with higher (SI ≥0.5), very high (SI ≥0.7), and the highest potential (SI ≥0.9) for dust emission cover >1 670 000 km2, >560 000 km2, and >240 000 km2, respectively. In the Arctic HLD region (≥60∘ N), land area with SI ≥0.5 is 5.5 % (1 035 059 km2), area with SI ≥0.7 is 2.3 % (440 804 km2), and area with SI ≥0.9 is 1.1 % (208 701 km2). Minimum SI values in the northern HLD region are about 3 orders of magnitude smaller, indicating that the dust sources of this region greatly depend on weather conditions. Our spatial dust source distribution analysis modeling results showed evidence supporting a northern HLD belt, defined as the area north of 50∘ N, with a “transitional HLD-source area” extending at latitudes 50–58∘ N in Eurasia and 50–55∘ N in Canada and a “cold HLD-source area” including areas north of 60∘ N in Eurasia and north of 58∘ N in Canada, with currently “no dust source” area between the HLD and low-latitude dust (LLD) dust belt, except for British Columbia. Using the global atmospheric transport model SILAM, we estimated that 1.0 % of the global dust emission originated from the high-latitude regions. About 57 % of the dust deposition in snow- and ice-covered Arctic regions was from HLD sources. In the southern HLD region, soil surface conditions are favorable for dust emission during the whole year. Climate change can cause a decrease in the duration of snow cover, retreat of glaciers, and an increase in drought, heatwave intensity, and frequency, leading to the increasing frequency of topsoil conditions favorable for dust emission, which increases the probability of dust storms. Our study provides a step forward to improve the representation of HLD in models and to monitor, quantify, and assess the environmental and climate significance of HLD.

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Gassó, S., and O. Torres. "Temporal Characterization of Dust Activity in the Central Patagonia Desert (Years 1964–2017)." Journal of Geophysical Research: Atmospheres 124, no. 6 (March 25, 2019): 3417–34. http://dx.doi.org/10.1029/2018jd030209.

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Nocera, Ariadna C., Eloísa M. Giménez, Mariano J. Diez, María Valeria Retana, and Gesche Winkler. "Krill diel vertical migration in Southern Patagonia." Journal of Plankton Research 43, no. 4 (July 2021): 610–23. http://dx.doi.org/10.1093/plankt/fbab047.

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Abstract Diel vertical migration (DVM) of krill was studied throughout 36 h at a fixed station (46.05°S, 66.19°W; 98-m depth) located in the center of the San Jorge Gulf, Southern Patagonia area, during February 2014. Using an echosounder system, combined with an autonomous Video Plankton Recorder (Auto-VPR) and Jacknet samplings, we describe the migration pattern, the associated biomass and the macrozooplankton species involved. The net sampling and the Auto-VPR images allowed us to identify the krill species detected in the echosounder signals, which corresponded to Euphausia lucens, Euphausia vallentini and Nematoscelis megalops. The krill community followed a “normal pattern” of DVM, ascending at dusk (~18:30 h) and descending at dawn (~06:30 h), forming a dense layer near the bottom during the day. Krill vertical migration speed was estimated from the echogram data at ~ 1 cm s−1 (1 body length per s for 1-cm-long animal), and the integrated mean biomass was 57.8 g m−2. This study provides a description of temporal and spatial patterns of krill vertical distribution, which should be taken into account when studying the complexity of the SJG ecosystem dynamics and carbon flux.

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Crespi-Abril, Augusto César, Gaspar Soria, Antonella De Cian, and Claudio López-Moreno. "Roaring forties: An analysis of a decadal series of data of dust in Northern Patagonia." Atmospheric Environment 177 (March 2018): 111–19. http://dx.doi.org/10.1016/j.atmosenv.2017.11.019.

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Zanchetta, Giovanni, Adriano Ribolini, Matteo Ferrari, Monica Bini, Ilaria Isola, Marco Lezzerini, Carlo Baroni, et al. "Geochemical characteristics of the infilling of ground wedges at Puerto Deseado (Santa Cruz, Argentina): palaeoenvironmental and chronological implications." Andean Geology 45, no. 2 (March 5, 2018): 130. http://dx.doi.org/10.5027/andgeov45n2-3070.

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Ground wedge structures of cryogenic origin are common in the Quaternary sediments along the coast of the Patagonia, and their formation is related to climatic cold events experienced by this area in the Late Quaternary. The infilling sediments of two wedges generations were analyzed in the area of Puerto Deseado. Bulk chemistry (major elements), X-ray diffraction (XRD), morphoscopic observations with Scanning Electronic Microscope (SEM) and chemical analyses of volcanic glass shards were undertaken to provide indications about infilling sediment provenience, along with chronological constraint for wedge formation. Bulk chemistry and XRD patterns indicate a significant SiO2-enriched composition of the sediment infilling compared to the most of the loess deposits of the North Argentina and the present day dust originated in Patagonia. This was interpreted as due to the nature of the bedrock present over the Deseado Massif. SEM morphoscopic characteristics of glass shards evidence typical aeolian reworking features, with impact structures and indented edges of the volcanic fragments. Chemical analyses of the glass shards indicate that they were probably generated by the H0 eruption (17,300-17,400 cal yr BP) of the Hudson volcano. Volcanological data indicate that H0 eruption dispersed toward NE, but volcanic glasses were available for reworking due to a WNW component in the western wind direction. Over the Deseado Massif structural high the glass shards mixed with sediments enriched in SiO2, and were eventually deflated further to SE reaching the present coastal area and infilling the frost cracks. The age of the glass shards (17,300-17,400 cal yr BP) and that of the sandy layer affected by cryogenic structures (14,670±750 yr BP) well constrain to the Late Glacial both wedge generations.

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Gaiero, Diego M., Frederic Brunet, Jean-Luc Probst, and Pedro J. Depetris. "A uniform isotopic and chemical signature of dust exported from Patagonia: Rock sources and occurrence in southern environments." Chemical Geology 238, no. 1-2 (March 2007): 107–20. http://dx.doi.org/10.1016/j.chemgeo.2006.11.003.

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Folch, A., L. Mingari, M. S. Osores, and E. Collini. "Modeling volcanic ash resuspension – application to the 14–18 October 2011 outbreak episode in Central Patagonia, Argentina." Natural Hazards and Earth System Sciences Discussions 1, no. 5 (September 6, 2013): 4565–603. http://dx.doi.org/10.5194/nhessd-1-4565-2013.

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Abstract. Volcanic fallout deposits from the June 2011 Cordón Caulle eruption in Central Patagonia were remobilized in several occasions months after their emplacement. In particular, during 14–18 October 2011, an intense outbreak episode generated huge volcanic clouds that were dispersed across Argentina, causing multiple impacts in the environment, affecting the air quality and disrupting airports. Fine ash particles in volcanic fallout deposits can be resuspended under favourable meteorological conditions, particularly during strong wind episodes in arid environments having low soil moisture and poor vegetation coverage. In opposition to eruption-formed ash clouds, modeling of resuspension-formed ash clouds has received little attention. In consequence, there are no emission schemes specially developed and calibrated for volcanic ash, and no operational product exists to model and forecast the formation and dispersal of resuspension ash clouds. Here we implement three dust emission schemes of increasing complexity in the FALL3D tephra dispersal model and use the 14–18 October 2011 outbreak episode as a model test case. We calibrate the emission schemes and validate the results of the coupled WRF-ARW/FALL3D modeling system using satellite imagery and measurements of visibility (a quantity related to total suspended particle concentration at surface) and particulate matter (PM10) concentration at several meteorological and air quality stations sparse across Argentina and Uruguay. Our final goal is to test the capability of the modeling system to become, in the near future, an operational forecast product for volcanic ash resuspension events.

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Folch, A., L. Mingari, M. S. Osores, and E. Collini. "Modeling volcanic ash resuspension – application to the 14–18 October 2011 outbreak episode in central Patagonia, Argentina." Natural Hazards and Earth System Sciences 14, no. 1 (January 17, 2014): 119–33. http://dx.doi.org/10.5194/nhess-14-119-2014.

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Abstract. Volcanic fallout deposits from the June 2011 Cordón Caulle eruption on central Patagonia were remobilized in several occasions months after their emplacement. In particular, during 14–18 October 2011, an intense outbreak episode generated widespread volcanic clouds that were dispersed across Argentina, causing multiple impacts in the environment, affecting the air quality and disrupting airports. Fine ash particles in volcanic fallout deposits can be resuspended under favorable meteorological conditions, particularly during strong wind episodes in arid environments with low soil moisture and poor vegetation coverage. As opposed to eruption-formed ash clouds, modeling of resuspension-formed ash clouds has received little attention. In consequence, there are no emission schemes specially developed and calibrated for resuspended volcanic ash, and few operational products exists to model and forecast the formation and dispersal of resuspension ash clouds. Here we implement three dust emission schemes of increasing complexity in the FALL3D tephra dispersal model and use the 14–18 October 2011 outbreak episode as a model test case. We calibrate the emission schemes and validate the results of the coupled WRF–ARW (Weather Research and Forecasting – Advanced Research WRF)/FALL3D modeling system using satellite imagery and measurements of visibility (a quantity related to total suspended particle concentration at the surface) and particulate matter (PM10) concentration at several meteorological and air quality stations located at Argentina and Uruguay. Our final goal is to test the capability of the modeling system to become, in the near future, an operational forecast product for volcanic ash resuspension events.

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Lisé-Pronovost, Agathe, Guillaume St-Onge, Claudia Gogorza, Torsten Haberzettl, Guillaume Jouve, Pierre Francus, Christian Ohlendorf, Catalina Gebhardt, and Bernd Zolitschka. "Rock-magnetic proxies of wind intensity and dust since 51,200 cal BP from lacustrine sediments of Laguna Potrok Aike, southeastern Patagonia." Earth and Planetary Science Letters 411 (February 2015): 72–86. http://dx.doi.org/10.1016/j.epsl.2014.11.007.

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Gong, Xianda, Martin Radenz, Heike Wex, Patric Seifert, Farnoush Ataei, Silvia Henning, Holger Baars, Boris Barja, Albert Ansmann, and Frank Stratmann. "Significant continental source of ice-nucleating particles at the tip of Chile's southernmost Patagonia region." Atmospheric Chemistry and Physics 22, no. 16 (August 19, 2022): 10505–25. http://dx.doi.org/10.5194/acp-22-10505-2022.

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Abstract. The sources and abundance of ice-nucleating particles (INPs) that initiate cloud ice formation remain understudied, especially in the Southern Hemisphere. In this study, we present INP measurements taken close to Punta Arenas, Chile, at the southernmost tip of South America from May 2019 to March 2020, during the Dynamics, Aerosol, Cloud, And Precipitation Observations in the Pristine Environment of the Southern Ocean (DACAPO-PESO) campaign. The highest ice nucleation temperature was observed at −3 ∘C, and from this temperature down to ∼-10 ∘C, a sharp increase of INP number concentration (NINP) was observed. Heating of the samples revealed that roughly 90 % and 80 % of INPs are proteinaceous-based biogenic particles at >-10 and −15 ∘C, respectively. The NINP at Punta Arenas is much higher than that in the Southern Ocean, but it is comparable with an agricultural area in Argentina and forestry environment in the US. Ice active surface site density (ns) is much higher than that for marine aerosol in the Southern Ocean, but comparable to English fertile soil dust. Parameterization based on particle number concentration in the size range larger than 500 nm (N>500 nm) from the global average (DeMott et al., 2010) overestimates the measured INP, but the parameterization representing biological particles from a forestry environment (Tobo et al., 2013) yields NINP comparable to this study. No clear seasonal variation of NINP was observed. High precipitation is one of the most important meteorological parameters to enhance the NINP in both cold and warm seasons. A comparison of data from in situ and lidar measurements showed good agreement for concentrations of large aerosol particles (>500 nm) when assuming continental conditions for retrieval of the lidar data, suggesting that these particles were well mixed within the planetary boundary layer (PBL). This corroborates the continental origin of these particles, consistent with the results from our INP source analysis. Overall, we suggest that a high NINP of biogenic INPs originated from terrestrial sources and were added to the marine air masses during the overflow of a maximum of roughly 150 km of land before arriving at the measurement station.

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Weber, M. E., G. Kuhn, D. Sprenk, C. Rolf, C. Ohlwein, and W. Ricken. "Dust transport from Patagonia to Antarctica – A new stratigraphic approach from the Scotia Sea and its implications for the last glacial cycle." Quaternary Science Reviews 36 (March 2012): 177–88. http://dx.doi.org/10.1016/j.quascirev.2012.01.016.

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36

Pike, Sarah. "Leaving Traces." Journal of Festive Studies 5 (November 13, 2023): 91–109. http://dx.doi.org/10.33823/jfs.2023.5.1.115.

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Transformative events are described by participants as ephemeral, appearing in and then disappearing from particular landscapes. What were cities teeming with costumed participants, art, and music seem to become “empty” deserts and meadows once again. Most transformative events have some version of the rule “Leave No Trace,” yet they leave many kinds of traces, material and immaterial, intentional and unintentional. What matter stays on-site, altering the land and what comes back to the other “home” that is lived in the rest of the year, altering participants’ lives away from event spaces? This article will focus on material traces, generally unintentional, left by some events in the western United States, including Burning Man (Nevada), Symbiosis/Oregon Eclipse/Global Eclipse (California, Oregon, Patagonia), Beloved (Oregon), and Lucidity (California). What is left behind includes impacts on the land and nonhuman species at event sites, the carbon footprints of events, the trash, ash, and other detritus that remains behind. Traces that are carried away and taken home to participants’ other homes away from event sites include material aspects—dust, mud, ash, sun exposure—absorbed by the bodies of participants. This article explores ways in which we might account for and understand the ongoing material effects of transformation on event participants’ bodies and on event sites. It focuses on continuities as well as discontinuities between transformative events and the “default world” or “mundania,” and the various tensions between heterotopia and home. The article draws on ideas of “porosity” to explore lasting—not ephemeral—material transformations of event participants, human and nonhuman.

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Andersen, Stig. "Revision of European species of Phytomyptera Rondani (Diptera: Tachinidae)." Insect Systematics & Evolution 19, no. 1 (1988): 43–80. http://dx.doi.org/10.1163/187631289x00050.

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AbstractBased on apomorphic characters of the male and female genitalia, evidence is provided for the monophyly of genus Phytomyptera Rondani (incl. Elfia Robineau-Desvoidy) and its placement in the monophyletic tribe Graphogastrini Townsend (= Elfiini Tschorsnig). A complete, annotated list of generic names regarded synonymous with Phytomyptera is given. The systematic position of Graphogastrini is discussed, with a key to the included genera. The 15 Palaearctic species of Phytomyptera are treated in a key, while a detailed survey is given of the 12 species presently known from Europe. The different species are mainly characterized by previously ignored, strongly diagnostic features of the male and female genitalia. Host relationships and other biological aspects are summarized, and the taxonomic importance of various characters of the adults and immatures is evaluated. Special emphasis is given to the structure of the aedeagus which primitively is a very complex organ with three outlets (gonopores) formed by the endophallus, here defined as a more or less sclerotized distal section of the sperm duct. This typically forms a capsule with three tubular exit branches. Based on a phylogenetic character analysis, the Palaearctic species are referred to five species-groups used in the construction of a cladogram. Three nominal species in Phytomyptera. minutissima (Zetterstedt), riedeli (Villeneuve) and vaccinii Sintenis, are removed from synonymy (spp. rev.). P. vivipara (Brauer & Bergenstamm) = P. minutissima (Zetterstedt) (syn. rev.), and P. gracilariae (Hering) = P. vaccinii Sintenis (syn. n.). Two Patagonian species are removed from Phytomyptera: vibrissata Aldrich to the closely related genus Planomyia Aldrich (comb. n.), and interrupta Aldrich which seems referable to tribe Leskiini.

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38

Valdés, Ángel. "Phylogenetic systematics of "Bathydoris" s.l. Bergh, 1884 (Mollusca, Nudibranchia), with the description of a new species from New Caledonian deep waters." Canadian Journal of Zoology 80, no. 6 (June 1, 2002): 1084–99. http://dx.doi.org/10.1139/z02-085.

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There are six valid species in the traditional genus Bathydoris, all of them found in polar or deep waters: Bathydoris abyssorum Bergh, 1884 (from the deep equatorial Pacific Ocean), Bathydoris ingolfiana Bergh, 1899 (from Greenland), Bathydoris hodgsoni Eliot, 1907 (from Antarctic and subantarctic waters), Bathydoris clavigera Thiele, 1912 (from the Argentinean deep-sea basin and Antarctica), Bathydoris aioca Ev. Marcus and Er. Marcus, 1962 (from deep waters off California), and a new species, Bathydoris spiralis (from deep waters off New Caledonia). Bathydoris patagonica Kaiser, 1980 and Bathydoris violacea Baranets, 1993 are regarded as synonyms of B. hodgsoni and B. clavigera, respectively. Bathydoris spiralis is clearly distinguishable from other members of the genus mainly in having a triaulic reproductive system and a very elongated, spirally coiled deferent duct. Examination of the holotype of B. violacea revealed that it is a synonym of B. clavigera. Bathydoris vitjazi Minichev, 1969 is most likely a synonym of B. hodgsoni, but is provisionally regarded as nomen dubium until more material becomes available. The phylogenetic hypothesis supports the monophyly of the Anthobranchia but shows that the genus Bathydoris is paraphyletic. Species of Bathydoris are divided into two clades, one of them also containing the phanerobranch and cryptobranch dorids. Bathydoris type species B. abyssorum retains its name and diagnosis, but B. clavigera and B. spiralis are excluded from this genus. They are, however, provisionally maintained in "Bathydoris" s.l., a likely paraphyletic group. This result shows some incongruities between the traditional nomenclatural system and phylogenetic systematics.

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Li, Fuyu, Paul Ginoux, and V. Ramaswamy. "Transport of Patagonian dust to Antarctica." Journal of Geophysical Research 115, no. D18 (September 28, 2010). http://dx.doi.org/10.1029/2009jd012356.

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40

Wyatt, Neil J., Antony Birchill, Simon Ussher, Angela Milne, Heather A. Bouman, Elizabeth Shoenfelt Troein, Katsiaryna Pabortsava, et al. "Phytoplankton responses to dust addition in the Fe–Mn co-limited eastern Pacific sub-Antarctic differ by source region." Proceedings of the National Academy of Sciences 120, no. 28 (July 3, 2023). http://dx.doi.org/10.1073/pnas.2220111120.

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The seasonal availability of light and micronutrients strongly regulates productivity in the Southern Ocean, restricting biological utilization of macronutrients and CO 2 drawdown. Mineral dust flux is a key conduit for micronutrients to the Southern Ocean and a critical mediator of multimillennial-scale atmospheric CO 2 oscillations. While the role of dust-borne iron (Fe) in Southern Ocean biogeochemistry has been examined in detail, manganese (Mn) availability is also emerging as a potential driver of past, present, and future Southern Ocean biogeochemistry. Here, we present results from fifteen bioassay experiments along a north–south transect in the undersampled eastern Pacific sub-Antarctic zone. In addition to widespread Fe limitation of phytoplankton photochemical efficiency, we found further responses following the addition of Mn at our southerly stations, supporting the importance of Fe–Mn co-limitation in the Southern Ocean. Moreover, addition of different Patagonian dusts resulted in enhanced photochemical efficiency with differential responses linked to source region dust characteristics in terms of relative Fe/Mn solubility. Changes in the relative magnitude of dust deposition, combined with source region mineralogy, could hence determine whether Fe or Mn limitation control Southern Ocean productivity under future as well as past climate states.

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Cosentino, N. J., D. M. Gaiero, and F. Lambert. "Present‐Day Patagonian Dust Emissions: Combining Surface Visibility, Mass Flux, and Reanalysis Data." Journal of Geophysical Research: Atmospheres 126, no. 16 (August 11, 2021). http://dx.doi.org/10.1029/2020jd034459.

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Cosentino, N. J., L. A. Ruiz‐Etcheverry, G. L. Bia, L. E. Simonella, R. Coppo, G. Torre, M. Saraceno, V. M. Tur, and D. M. Gaiero. "Does Satellite Chlorophyll‐a Respond to Southernmost Patagonian Dust? A Multi‐year, Event‐Based Approach." Journal of Geophysical Research: Biogeosciences 125, no. 12 (December 2020). http://dx.doi.org/10.1029/2020jg006073.

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43

Weber, Michael E., Ian Bailey, Sidney R. Hemming, Yasmina M. Martos, Brendan T. Reilly, Thomas A. Ronge, Stefanie Brachfeld, et al. "Antiphased dust deposition and productivity in the Antarctic Zone over 1.5 million years." Nature Communications 13, no. 1 (April 19, 2022). http://dx.doi.org/10.1038/s41467-022-29642-5.

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AbstractThe Southern Ocean paleoceanography provides key insights into how iron fertilization and oceanic productivity developed through Pleistocene ice-ages and their role in influencing the carbon cycle. We report a high-resolution record of dust deposition and ocean productivity for the Antarctic Zone, close to the main dust source, Patagonia. Our deep-ocean records cover the last 1.5 Ma, thus doubling that from Antarctic ice-cores. We find a 5 to 15-fold increase in dust deposition during glacials and a 2 to 5-fold increase in biogenic silica deposition, reflecting higher ocean productivity during interglacials. This antiphasing persisted throughout the last 25 glacial cycles. Dust deposition became more pronounced across the Mid-Pleistocene Transition (MPT) in the Southern Hemisphere, with an abrupt shift suggesting more severe glaciations since ~0.9 Ma. Productivity was intermediate pre-MPT, lowest during the MPT and highest since 0.4 Ma. Generally, glacials experienced extended sea-ice cover, reduced bottom-water export and Weddell Gyre dynamics, which helped lower atmospheric CO2 levels.

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Otero, L., P. Ristori, R. D’Elia, A. Rosales, and E. Quel. "Plumas de polvo en la Patagonia Argentina, marzo de 2009 Dust over the Patagonia Argentina, March 2009." Anales AFA, 2010, 272–75. http://dx.doi.org/10.31527/analesafa.2010.21.272.

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This work studies the dust clouds microphysical properties from the Pampa and the Patagonia region. This kind of events occurred regularly during the dry season of 2008. It analyzes in particular the episode that occurred on March 28th, 2009 by means of a sunphotometer from the AERONET global network administrated by NASA, and radiometer both located at the “Laboratorio de Física de la Atmósfera, Facultad de Ingeniería, Universidad Nacional de la Patagonia” (43,2° S, 65,3° O, 15,0 m), at Trelew, in Chubut. The geographical extent of this event was evidenced by the AQUA satellite images. An aerosol characterization shows a SSA of 0.9 and an aerosol optical thickness of 0.8 measured at 440 nm. This means an effective direct sun radiation blocking factor of 50% in the visible region of the electromagnetic spectrum.

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Gassó, Santiago, and Ariel F. Stein. "Does dust from Patagonia reach the sub-Antarctic Atlantic Ocean?" Geophysical Research Letters 34, no. 1 (January 3, 2007). http://dx.doi.org/10.1029/2006gl027693.

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Shi, Cuicui, Rui Mao, Dao-Yi Gong, Seong-Joong Kim, Xingya Feng, Yijie Sun, and Huilong Dong. "Increased dust transport from Patagonia to eastern Antarctica during 2000–2020." Global and Planetary Change, July 2023, 104186. http://dx.doi.org/10.1016/j.gloplacha.2023.104186.

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Pullen, Alex, David L. Barbeau, Andrew L. Leier, Jordan T. Abell, Madison Ward, Austin Bruner, and Mary Kate Fidler. "A westerly wind dominated Puna Plateau during deposition of upper Pleistocene loessic sediments in the subtropical Andes, South America." Nature Communications 13, no. 1 (June 14, 2022). http://dx.doi.org/10.1038/s41467-022-31118-5.

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AbstractThe Tafí del Valle depression (~27° S) in the eastern Andes of Argentina provides a record of late Pleistocene dust deposition in the subtropics of South America. We present large-n U-Pb geochronology data for detrital zircons from upper Pleistocene loess-paleosol deposits. When compared to regional data, the age spectra from the Tafí del Valle samples are most like the southern Puna Plateau, supporting derivation largely from the west and northwest. This runs counter to hypotheses suggesting these loessic sediments were derived from the low elevation plains to the east or extra-Andean Patagonia. Mapping of linear wind erosion features on the Puna Plateau yield a mean orientation of 125.7° (1 s.d. = 12.4°). These new data and existing records are consistent with a westerly-northwesterly dominated (upper- and lower-level) wind system over the southern Puna Plateau (to at least ~27° S) during periods of high dust accumulation in Tafí del Valle.

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Crespi-Abril, Augusto César, Gaspar Soria, Elena Barbieri, Flavio Paparazzo, Antonella De Cian, and Rodrigo J. Gonçalves. "Dynamics and Characterization of Aeolian Dust Deposition from a Burned Shrubland at Chubut Coastal Patagonia in Argentina." Earth Systems and Environment, October 31, 2021. http://dx.doi.org/10.1007/s41748-021-00272-z.

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Jarvis, Paul A., Costanza Bonadonna, Lucia Dominguez, Pablo Forte, Corine Frischknecht, Donaldo Bran, Rigoberto Aguilar, et al. "Aeolian Remobilisation of Volcanic Ash: Outcomes of a Workshop in the Argentinian Patagonia." Frontiers in Earth Science 8 (November 27, 2020). http://dx.doi.org/10.3389/feart.2020.575184.

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During explosive volcanic eruptions, large quantities of tephra can be dispersed and deposited over wide areas. Following deposition, subsequent aeolian remobilisation of ash can potentially exacerbate primary impacts on timescales of months to millennia. Recent ash remobilisation events (e.g., following eruptions of Cordón Caulle 2011; Chile, and Eyjafjallajökull 2010, Iceland) have highlighted this to be a recurring phenomenon with consequences for human health, economic sectors, and critical infrastructure. Consequently, scientists from observatories and Volcanic Ash Advisory Centers (VAACs), as well as researchers from fields including volcanology, aeolian processes and soil sciences, convened at the San Carlos de Bariloche headquarters of the Argentinian National Institute of Agricultural Technology to discuss the “state of the art” for field studies of remobilised deposits as well as monitoring, modeling and understanding ash remobilisation. In this article, we identify practices for field characterisation of deposits and active processes, including mapping, particle characterisation and sediment traps. Furthermore, since forecast models currently rely on poorly-constrained dust emission schemes, we call for laboratory and field measurements to better parameterise the flux of volcanic ash as a function of friction velocity. While source area location and extent are currently the primary inputs for dispersion models, once emission schemes become more sophisticated and better constrained, other parameters will also become important (e.g., source material volume and properties, effective precipitation, type and distribution of vegetation cover, friction velocity). Thus, aeolian ash remobilisation hazard and associated impact assessment require systematic monitoring, including the development of a regularly-updated spatial database of resuspension source areas.

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Crespi-Abril, Augusto César, Gaspar Soria, Elena Barbieri, Flavio Paparazzo, Antonella De Cian, and Rodrigo J. Gonçalves. "Correction to: Dynamics and Characterization of Aeolian Dust Deposition from a Burned Shrubland at Chubut Coastal Patagonia in Argentina." Earth Systems and Environment, February 18, 2022. http://dx.doi.org/10.1007/s41748-022-00299-w.

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Journal articles on the topic 'Patagonian dust'

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