Similarity between turbulent fluctuations of scalars in lake environment




Monin-Obukhov Similarity Theory, Similarity functions, Atmospheric turbulence


This paper presents an evaluation of scalar similarity and scalar flux similarity of measurements above the water surface of the Itaipu hydroelectric reservoir. The scalars studied were: CO2 mixing ratio (rc), air temperature (θ), specific air humidity (q) and the vertical wind velocity (w). With the variance method it was found that the vertical wind velocity is in agreement with Monin-Obukhov Similarity Theory. On the other hand, the other scalars presented larger deviations in relation to the theoretical prediction. The worst results were for air temperature and mixing ratio of CO2. The most similar scalars were θ and q, with the most frequent correlation coefficient varying in the range [0.55:0.64] for measurements in unstable atmospheric conditions and in the [−0.85:−0.75] range for measurements under stable atmospheric conditions. Regarding the scalar fluxes, they presented greater similarity to each other than the scalars themselves.


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Author Biographies

Fernando Augusto Silveira Armani, Universidade Federal do Paraná, Pontal do Paraná, PN

Professor Adjunto do curso de Engenharia Ambiental e Sanitária da UFPR. Engenheiro Ambiental, Mestre em Engenharia Ambiental e Doutor em Mecânica Computacional

Nelson Luís Dias, Universidade Federal do Paraná, Curitiba, PN

Atualmente Professor Titular do Departamento de Engenharia Ambiental da UFPR, e pesquisador em Hidrologia, Turbulência e Meteorologia da Camada-Limite Atmosférica

Dornelles Vissotto Junior, Universidade Federal do Paraná, Curitiba, PN

Mestre e Doutor em Mecânica Computacional, Pesquisador em micrometeorologia e inteligência artificial, Extensionista em inovação e educação empreendedora. Chefe da Unidade de Creditação da Extensão UFPR. Mentor e Analista de Investimentos de Venture Capital e Smart Money para o Labiie


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How to Cite

Armani, F. A. S., Dias, N. L., & Vissotto Junior, D. (2020). Similarity between turbulent fluctuations of scalars in lake environment. Ciência E Natura, 42, e13.

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