@Article{OliveiraAceMorZimTei:2013:NoInCo,
               author = "Oliveira, Pablo E. S. and Acevedo, Otavio Costa and Moraes, 
                         Osvaldo Luiz Leal de and Zimermann, Hans R. and Teichrieb, 
                         Claudio",
          affiliation = "Departamento de F{\'{\i}}sica, Universidade Federal de Santa 
                         Maria, Santa Maria, Brazil and {} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)}",
                title = "Nocturnal intermittent coupling between the interior of a pine 
                         forest and the air above it",
              journal = "Boundary-Layer Meteorology",
                 year = "2013",
               volume = "146",
               number = "1",
                pages = "45--64",
             keywords = "canopy exchange, carbon dioxide fluxes, decoupling, energy fluxes, 
                         micrometeorology, multiresolution decomposition, stable boundary 
                         layer.",
             abstract = "A 1-year set of measurements of CO2 and energy turbulent fluxes 
                         above and within a 25-m pine forest in southern Brazil is 
                         analyzed. The study focuses on the coupling state between two 
                         levels and its impact on flux determination by the eddy-covariance 
                         method. The turbulent series are split in their typical temporal 
                         scales using the multiresolution decomposition, a method that 
                         allows proper identification of the time scales of the turbulent 
                         events. Initially, four case studies are presented: a continually 
                         turbulent, a continually calm, a calm then turbulent, and an 
                         intermittent night. During transitions from calm to turbulent, 
                         large scalar fluxes of opposing signs occur at both levels, 
                         suggesting the transference of air accumulated in the canopy 
                         during the stagnant period both upwards and downwards. Average 
                         fluxes are shown for the entire period as a function of turbulence 
                         intensity and a canopy Richardson number, used as an indicator of 
                         the canopy coupling state. Above the canopy, CO2 and sensible heat 
                         fluxes decrease in magnitude both at the neutral and at the very 
                         stable limit, while below the canopy they increase monotonically 
                         with the canopy Richardson number. Latent heat fluxes decrease at 
                         both levels as the canopy air becomes more stable. The average 
                         temporal scales of the turbulent fluxes at both levels approach 
                         each other in neutral conditions, indicating that the levels are 
                         coupled in that case. Average CO2 fluxes during turbulent periods 
                         that succeed very calm ones are appreciably larger than the 
                         overall average above the canopy and smaller than the average or 
                         negative within the canopy, indicating that the transfer of air 
                         accumulated during calm portions at later turbulent intervals 
                         affects the flux average. The implications of this process for 
                         mean flux determination are discussed.",
                  doi = "10.1007/s10546-012-9756-z",
                  url = "http://dx.doi.org/10.1007/s10546-012-9756-z",
                 issn = "0006-8314 and 1573-1472",
                label = "lattes: 0593135962205202 4 OliveiraAcAcMoZiTe:2013:NoInCo",
             language = "en",
           targetfile = "Oliveira_Nocturnal.PDF",
        urlaccessdate = "27 abr. 2024"
}