Further evidence for significant smoke transport from Africa to Amazonia

Baars, Holger; Ansmann, Albert; Althausen, Dietrich; Engelmann, Ronny; Artaxo, Paulo; Pauliquevis, Theotônio; Souza, R. A. F. D.

doi:10.1029/2011gl049200

Cited by 94 publications

(117 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…3 some significant episodic enhancements in the coarse particle mass. These episodes were associated with dust transport from the Sahara desert, documented in several studies (Formenti et al, 2001;Swap et al, 1992Swap et al, , 1996Koren et al, 2006;Ansmann et al, 2009;Baars et al, 2011;Ben-Ami et al, 2010). Time series of fine and coarse mode BC E concentration are shown in Fig.…”

Section: Aerosol Measurementsmentioning

confidence: 99%

See 1 more Smart Citation

Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution

et al. 2012

Self Cite

View full text Add to dashboard Cite

Abstract. In this analysis a 3.5 years data set of aerosol and precipitation chemistry, obtained in a remote site in Central Amazonia (Balbina, (1 • 55 S, 59 • 29 W, 174 m a.s.l.), about 200 km north of Manaus) is discussed. Aerosols were sampled using stacked filter units (SFU), which separate fine (d < 2.5 µm) and coarse mode (2.5 µm < d < 10.0 µm) aerosol particles. Filters were analyzed for particulate mass (PM), Equivalent Black Carbon (BC E ) and elemental composition by Particle Induced X-Ray Emission (PIXE). Rainwater samples were collected using a wet-only sampler and samples were analyzed for pH and ionic composition, which was determined using ionic chromatography (IC). Natural sources dominated the aerosol mass during the wet season, when it was predominantly of natural biogenic origin mostly in the coarse mode, which comprised up to 81 % of PM 10 . Biogenic aerosol from both primary emissions and secondary organic aerosol dominates the fine mode in the wet season, with very low concentrations (average 2.2 µg m −3 ). Soil dust was responsible for a minor fraction of the aerosol mass (less than 17 %). Sudden increases in the concentration of elements as Al, Ti and Fe were also observed, both in fine and coarse mode (mostly during the April-may months), which we attribute to episodes of Saharan dust transport. During the dry periods, a significant contribution to the fine aerosols loading was observed, due to the large-scale transport of smoke from biomass burning in other portions of the Amazon basin. This contribution is associated with the enhancement of the concentration of S, K, Zn and BC E . Chlorine, which is commonly associated to sea salt and also to biomass burning emissions, presented higher concentration not only during the dry season but also for the April-June months, due to the establishment of more favorable meteorological conditions to the transport of Atlantic air masses to Central Amazonia. The chemical composition of rainwater was similar to those ones observed in other remote sites in tropical forests. The volume-weighted mean (VWM) pH was 4.90. The most important contribution to acidity was from weak organic acids. The organic acidity was predominantly associated with the presence of acetic acid instead of formic acid, which is more often observed in pristine tropical areas. Wet deposition rates for major species did not differ significantly between dry and wet season, except for NH + 4 , citrate and acetate, which had smaller deposition rates during dry season. While biomass burning emissions were clearly identified in the aerosol component, it did not present a clear signature in rainwater. The biogenic component and the long-range transport of sea salt were observed both in aerosols and rainwater composition. The results shown here indicate that in Central Amazonia it is still possible to observe quite pristine atmospheric conditions, relatively free of anthropogenic influences.

show abstract

Section: Aerosol Measurementsmentioning

confidence: 99%

“…However, as shown in the discussion of the Principal Component Analysis, it was in April and May that we observed bursts of this elements. We attribute it to the transport of Saharan dust, which has been shown to be more likely to happen during these months (Baars et al, 2011).…”

Section: Ti Fe Al Si and Camentioning

confidence: 99%

Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…During the dry season in central Africa, a belt with strong fire activity extending over several thousands of kilometers from western to eastern Africa produces large amounts of fire smoke which is carried towards the Americas by dust-laden air (Ansmann et al, 2009;Ben-Ami et al, 2010;Baars et al, 2011). The case, shown in Fig.…”

Section: Saharan Dust Mixed With Biomass-burning Smokementioning

confidence: 99%

“…Smoke-related particle extinction coefficients ranged from 25-100 Mm −1 between 1000 and 5000 m height during this period and indicated smoke particle mass concentrations of 10-35 µg m −3 . It is interesting to note that Baars et al (2011) The question may arise why the layer with strong dust backscatter over Cape Verde coincides with the marine boundary layer. This results from very different air mass flows with winds from northeast in the boundary layer and from southerly direction within the smoke-containing air above 600 m height .…”

Section: Saharan Dust Mixed With Biomass-burning Smokementioning

confidence: 99%

Profiling of fine and coarse particle mass: case studies of Saharan dust and Eyjafjallajökull/Grimsvötn volcanic plumes

et al. 2012

Self Cite

View full text Add to dashboard Cite

Abstract. The polarization lidar photometer networking (POLIPHON) method introduced to separate coarse-mode and fine-mode particle properties of Eyjafjallajökull volcanic aerosols in 2010 is extended to cover Saharan dust events as well. Furthermore, new volcanic dust observations performed after the Grimsvötn volcanic eruptions in 2011 are presented. The retrieval of particle mass concentrations requires mass-specific extinction coefficients. Therefore, a review of recently published mass-specific extinction coefficients for Saharan dust and volcanic dust is given. Case studies of four different scenarios corroborate the applicability of the profiling technique: (a) Saharan dust outbreak to central Europe, (b) Saharan dust plume mixed with biomass-burning smoke over Cape Verde, and volcanic aerosol layers originating from (c) the Eyjafjallajökull eruptions in 2010 and (d) the Grimsvötn eruptions in 2011. Strong differences in the vertical aerosol layering, aerosol mixing, and optical properties are observed for the different volcanic events.

show abstract

“…However, the regionally and biogenically dominated background state of the atmosphere is frequently perturbed by the episodic advection of 5 long-range transport (LRT) aerosols from Africa in air masses that bypass the major rain fields and, therefore, 'survive' the intense scavenging (Moran-Zuloaga et al, 2017). The frequent intrusion of LRT aerosols is a characteristic feature during the Amazonian wet season and represents a strong and important impact on the Amazonian ecosystem (e.g., Chen et al, 2009;Bristow et al, 2010;Baars et al, 2011;Abouchami et al, 2013;Yu et al, 2015;Rizzolo et al, 2016). These LRT plumes mostly comprise a complex mixture of Saharan dust, African 10 biomass burning smoke, and marine aerosols from the transatlantic air passage (e.g., Talbot et al, 1990;Swap et al, 1992;Glaser et al, 2015).…”

Section: Aerosol and Ccn Time Series For Representative Wet Season Comentioning

confidence: 99%

Long-term observations of cloud condensation nuclei in the Amazon rain forest – Part 2: Variability and characteristic differences under near-pristine, biomass burning, and long-range transport conditions

Pöhlker

Ditas

Saturno

et al. 2017

Preprint

View full text Add to dashboard Cite

Size-resolved measurements of atmospheric aerosol and cloud condensation nuclei (CCN) concentrations and hygroscopicity were conducted at the remote Amazon Tall Tower Observatory (ATTO) in the central Amazon Basin over a full seasonal cycle (Mar 2014 -Feb 2015. In a companion part 1 paper, we presented an in-depth CCN characterization based on annually as well as seasonally averaged time intervals and discuss different para-5 metrization strategies to represent the Amazonian CCN cycling in modelling studies (M. Pöhlker et. al. 2016b).The present part 2 study analyzes the aerosol and CCN variability in original time resolution and, thus, resolves aerosol advection and transformation for the following case studies, which represent the most characteristic states of the Amazonian atmosphere: ), a mostly organic particle composition, and relatively low hygroscopicity levels (κAit = 0.12 vs. κacc = 0.18). The NP CCN efficiency spectrum shows that the CCN population is sensitive to changes in supersaturation (S) over a wide S range. Atmos. Chem. Phys. Discuss., https://doi

show abstract

Further evidence for significant smoke transport from Africa to Amazonia

Cited by 94 publications

References 21 publications

Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution

Aerosol and precipitation chemistry measurements in a remote site in Central Amazonia: the role of biogenic contribution

Profiling of fine and coarse particle mass: case studies of Saharan dust and Eyjafjallajökull/Grimsvötn volcanic plumes

Long-term observations of cloud condensation nuclei in the Amazon rain forest – Part 2: Variability and characteristic differences under near-pristine, biomass burning, and long-range transport conditions

Contact Info

Product

Resources

About