author = "Darbyshire, Eoghan and Morgan, Willian T. and Allan, James D. and 
                         Liu, Dantong and Flynn, Michael J. and Dorsey, James R. and 
                         O'Shea, Sebastian J. and Lowe, Douglas and Szpek, Kate and 
                         Marenco, Franco and Johnson, Ben T. and Bauguitte, Stephane and 
                         Haywood, Jim M. and Brito, Joel F. and Artaxo, Paulo and Longo, 
                         Karla Maria and Coe, Hugh",
          affiliation = "{University of Manchester} and {University of Manchester} and 
                         {University of Manchester} and {University of Manchester} and 
                         {University of Manchester} and {University of Manchester} and 
                         {University of Manchester} and {University of Manchester} and {Met 
                         Office} and {Met Office} and {Met Office} and , University of 
                         Cranfield and {Met Office} and {Universidade de S{\~a}o Paulo 
                         (USP)} and {Universidade de S{\~a}o Paulo (USP)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {University of 
                title = "The vertical distribution of biomass burning pollution over 
                         tropical South America from aircraft in situ measurements during 
              journal = "Atmospheric Chemistry and Physics",
                 year = "2019",
               volume = "19",
               number = "9",
                pages = "5771--5790",
                month = "May",
             abstract = "We examine processes driving the vertical distribution of biomass 
                         burning pollution following an integrated analysis of over 200 
                         pollutant and meteorological profiles measured in situ during the 
                         South AMerican Biomass Burning Analysis (SAMBBA) field experiment. 
                         This study will aid future work examining the impact of biomass 
                         burning on weather, climate and air quality.</p> During the dry 
                         season there were significant contrasts in the composition and 
                         vertical distribution of haze between western and eastern regions 
                         of tropical South America. Owing to an active or residual 
                         convective mixing layer, the aerosol abundance was similar from 
                         the surface to <span classCombining double low 
                         line{"}inline-formula{"}>\ĝ1/41.5</span>\ <span 
                         classCombining double low line{"}inline-formula{"}>km</span> in 
                         the west and <span classCombining double low 
                         line{"}inline-formula{"}>\ĝ1/43</span>\ <span 
                         classCombining double low line{"}inline-formula{"}>km</span> in 
                         the east. Black carbon mass loadings were double as much in the 
                         east (1.7\ <span classCombining double low 
                         line{"}inline-formula{"}>\μg m\ĝ'3</span>) than the 
                         west (0.85\ <span classCombining double low 
                         line{"}inline-formula{"}>\μg m\ĝ'3</span>), but 
                         aerosol scattering coefficients at 550\ <span 
                         classCombining double low line{"}inline-formula{"}>nm</span> were 
                         similar (<span classCombining double low 
                         line{"}inline-formula{"}>\ĝ1/4120</span>\ <span 
                         classCombining double low 
                         line{"}inline-formula{"}>Mm\ĝ'1</span>), as too were CO 
                         near-surface concentrations (310-340\ <span classCombining 
                         double low line{"}inline-formula{"}>ppb</span>). We attribute 
                         these contrasts to the more flaming combustion of Cerrado fires in 
                         the east and more smouldering combustion of deforestation and 
                         pasture fires in the west. Horizontal wind shear was important in 
                         inhibiting mixed layer growth and plume rise, in addition to 
                         advecting pollutants from the Cerrado regions into the remote 
                         tropical forest of central Amazonia. Thin layers above the mixing 
                         layer indicate the roles of both plume injection and shallow moist 
                         convection in delivering pollution to the lower free troposphere. 
                         However, detrainment of large smoke plumes into the upper free 
                         troposphere was very infrequently observed. Our results reiterate 
                         that thermodynamics control the pollutant vertical distribution 
                         and thus point to the need for correct model representation so 
                         that the spatial distribution and vertical structure of biomass 
                         burning smoke is captured.</p> We observed an increase of aerosol 
                         abundance relative to CO with altitude both in the background haze 
                         and plume enhancement ratios. It is unlikely associated with 
                         thermodynamic partitioning, aerosol deposition or local non-fire 
                         sources. We speculate it may be linked to long-range transport 
                         from West Africa or fire combustion efficiency coupled to plume 
                         injection height. Further enquiry is required to explain the 
                         phenomenon and explore impacts on regional climate and air 
                  doi = "10.5194/acp-19-5771-2019",
                  url = "http://dx.doi.org/10.5194/acp-19-5771-2019",
                 issn = "1680-7316 and 1680-7324",
             language = "en",
           targetfile = "darbyshire_vertical.pdf",
        urlaccessdate = "14 abr. 2021"