@Article{MortariniDAOTSMABTGC:2022:CoStAn,
               author = "Mortarini, Luca and Dias J{\'u}nior, Cl{\'e}o Q. and Acevedo, 
                         Ot{\'a}vio Costa and Oliveira, Pablo E. S. and Tsokankunku, 
                         Anywhere and S{\"o}rgel, Matthias and Manzi, Antonio Ocimar and 
                         Ara{\'u}jo, Alessandro C. de and Brondani, Daiane V. and Toro, 
                         Ivan Maur{\'{\i}}cio Cely and Giostra, Umberto and Cava, 
                         Daniela",
          affiliation = "{Consiglio Nazionale delle Ricerche (ISAC-CNR)} and {Instituto 
                         Nacional de Pesquisas da Amaz{\^o}nia (INPA)} and {Instituto 
                         Nacional de Pesquisas da Amaz{\^o}nia (INPA)} and {Universidade 
                         Federal do Rio Grande do Norte (UFRN)} and {Max Planck Institute 
                         for Chemistry} and {Max Planck Institute for Chemistry} and 
                         {Instituto Nacional de Pesquisas Espaciais (INPE)} and {Embrapa 
                         Amaz{\^o}nia Oriental} and {Instituto Nacional de Pesquisas da 
                         Amaz{\^o}nia (INPA)} and {Universidade Federal de Santa Maria 
                         (UFSM)} and {Universit{\`a} degli Studi di Urbino} and {Consiglio 
                         Nazionale delle Ricerche (ISAC-CNR)}",
                title = "Vertical propagation of submeso and coherent structure in a tall 
                         and dense amazon forest in different stability conditions. PART 
                         II: Coherent structures analysis",
              journal = "Agricultural and Forest Meteorology",
                 year = "2022",
               volume = "322",
                pages = "e108993",
                month = "July",
             keywords = "Amazon forest, Canopy turbulence, Coherent structure, Mixing-layer 
                         analogy, Roughness sublayer.",
             abstract = "Observations of the vertical structure of the turbulent flow in 
                         different stability regimes above and within the Amazon Forest at 
                         the Amazon Tall Tower Observatory (ATTO) site have been presented 
                         in Part I. Here, the influence of stability on the inception and 
                         development of coherent structures is investigated. According to 
                         the mixing-layer analogy the coherent vortices that dominate the 
                         turbulent flows at the canopy-atmosphere interface are generated 
                         by hydrodynamical instabilities triggered by an inflection in the 
                         vertical profile of the mean wind speed at or near the canopy top. 
                         The coherent motions time, Tpeak and separation length scale, 
                         \Λ, depend on the shear length scale, Ls, close to the 
                         canopy top. The present analysis studies the characteristics of 
                         Ls, Tpeak and \Λ in the five stability regimes defined in 
                         Part I. The behaviour of Ls with stability is evaluated and 
                         parameterized. Ls increases with decreasing stability, presenting 
                         two asymptotes for large unstable and stable stratification and a 
                         linear behaviour close to neutral stratification. Coherent 
                         structures and their timescale are detected with an original 
                         method based on the autocorrelation functions of 5-min subsets of 
                         turbulent quantities. The vertical time scale is larger in neutral 
                         conditions and decreases for both increasing and decreasing 
                         stability. At the canopy top the separation length scale presents 
                         a linear dependence on Ls, whose slope is maximum in neutral 
                         conditions and decreases departing from neutrality. An original 
                         parameterization of the dependence of this slope on h/L, where h 
                         is the canopy height and L is the Obukhov length, is shown. 
                         Combining the parameterizations, the dependence of the separation 
                         length scale is finally presented. \Λ has a maximum for 
                         slightly unstable conditions, linearly decreases towards neutral 
                         and weakly stable stratifications and then it tends to zero for 
                         very intense unstable and stable stratifications.",
                  doi = "10.1016/j.agrformet.2022.108993",
                  url = "http://dx.doi.org/10.1016/j.agrformet.2022.108993",
                 issn = "0168-1923",
             language = "en",
           targetfile = "mortarini_2022_vertical.pdf",
        urlaccessdate = "16 jun. 2024"
}