Turbulent statistical characteristics associated to the north wind phenomenon in southern Brazil with application to turbulent diffusion

Arbage, Maria Cristina A.; Degrazia, Gervásio Annes; Welter, Guilherme Sausen; Roberti, Débora Regina; Acevedo, Otávio C.; Moraes, Osvaldo L. L.; Ferraz, Simone Erotildes Teleginski; Timm, Andréa Ucker; Moreira, Virnei Silva

doi:10.1016/j.physa.2008.02.068

Cited by 13 publications

(15 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the neutral and stable conditions, the values observed at the Linhares tower are almost identical to those of Hanna (1982) and shown in Table 2. The observed values for the ratio s i u 21 * in the unstable case approach those found by Panofsky and Dutton (1983) and Arbage et al (2008) dimensionless velocity standard deviation in neutral and unstable cases confirms the dominant local effect played by the wind shear in the turbulence generation in the vertical regions of the PBL nearest to the surface.…”

Section: Resultssupporting

confidence: 86%

Quasi-Experimental Determination of Turbulent Dispersion Parameters for Different Stability Conditions from a Tall Micrometeorological Tower

Martins

Degrazia

Acevedo

et al. 2018

Journal of Applied Meteorology and Climatology

View full text Add to dashboard Cite

Turbulent wind data measured by sonic anemometers installed at various heights on a 140-m-tall micrometeorological tower located at a coastal site are used to obtain vertical profiles of the velocity standard deviations σi, Lagrangian decorrelation local time scales TLi, and eddy diffusivities Kα for distinct stability conditions. The novelty of the study lies in the use of turbulent data directly measured over the extension of the atmospheric surface layer at a coastal site for that purpose. Furthermore, the approach employs the Hilbert–Huang transform to determine the wind energy spectral peak frequencies. These are applied to the asymptotic spectral equation from Taylor statistical diffusion theory to obtain the turbulent dispersion parameters, which are shown to generally agree well with those provided by a classical autocorrelation approach. For neutral and stable situations the vertical profiles of momentum eddy diffusivities agree well with those derived from the spectral and autocorrelation method. Additionally, the turbulent integral time scales and eddy diffusivities determined by the method at a coastal location are found to overestimate those predicted from analytical expressions based on continental field observations. The turbulence parameters found are suitable to be employed in air pollution dispersion models.

show abstract

Section: Resultssupporting

confidence: 86%

Quasi-Experimental Determination of Turbulent Dispersion Parameters for Different Stability Conditions from a Tall Micrometeorological Tower

Martins

Degrazia

Acevedo

et al. 2018

Journal of Applied Meteorology and Climatology

View full text Add to dashboard Cite

show abstract

“…By separately analyzing the environmental variables for these days, we observed that high VPD, low relative humidity of the air, high wind intensity reaching 4.7 m s −1 , and a high air temperature of about 30 • C did occur (Figure 2). These atypical days of high ET act values during AW were characterized by the "north wind phenomenon", corresponding to the occurrence of hot and humid wind coming from Amazonia and which intensifies near Santa Maria due to its particular topography [52]. For pasture land near the Mediterranean coast, Trepekli et al [10] reported maximum values for ET act of 8.2 mm d −1 in summer, the value of which is 15% greater than those found in our study.…”

Section: Evapotranspiration Variability In the Pampa Biomecontrasting

confidence: 69%

Evapotranspiration of the Brazilian Pampa Biome: Seasonality and Influential Factors

Rubert

Roberti

Pereira

et al. 2018

Water

View full text Add to dashboard Cite

Experimentally characterizing evapotranspiration (ET) in different biomes around the world is an issue of interest for different areas of science. ET in natural areas of the Brazilian Pampa biome has still not been assessed. In this study, the actual ET (ETact) obtained from eddy covariance measurements over two sites of the Pampa biome was analyzed. The objective was to evaluate the energy partition and seasonal variability of the actual ET of the Pampa biome. Results showed that the latent heat flux was the dominant component in available energy in both the autumn–winter (AW) and spring–summer (SS) periods. Evapotranspiration of the Pampa biome showed strong seasonality, with highest ET rates in the SS period. During the study period, approximately 65% of the net radiation was used for the evapotranspiration process in the Pampa biome. The annual mean ET rate was 2.45 mm d−1. ET did not show to vary significantly between sites, with daily values very similar in both sites. The water availability in the Pampa biome was not a limiting factor for ET, which resulted in a small difference between the reference ET and the actual ET. These results are helpful in achieving a better understanding of the temporal pattern of ET in relation to the landscape of the Pampa biome and its meteorological, soil, and vegetation characteristics.

show abstract

“…The average wind speed magnitudes remain high, with the highest values around 6 m.s −1 occurring between 10:00 and 14:00 LST. As a comparison, in the study by Arbage et al (2008), using data measured in a micrometeorological tower installed in Paraíso do Sul (29.74°S, 53.14°W) speeds of 7 m.s −1 were observed. In the period between 17:30 and 22:30 LST of the first day, the wind speed decreased (U ∼ 3 m.s −1 ), however, this value is still high when compared to the average (U ∼ 1.5 m.s −1 ) observed in the morning preceding the episode of VNOR (02:00 to 09:00 LST).…”

Section: Dynamic and Thermodynamic Analysis During Vnormentioning

confidence: 90%

“…These winds, that develop under pre-frontal environments, are known as "Vento Norte" (VNOR; Sartori, 2003;Anabor et al, 2005;Chamis and Nascimento, 2012;Stefanello et al, 2020). The VNOR is characterized by intense gusty winds accompanied by unseasonably high temperatures and drop in the dew points, and it affects the turbulence behavior in the PBL, impacting the transport and diffusion of scalar and vector species and evapotranspiration (Arbage et al, 2008). Furthermore, the strongest episodes of VNOR affect local essential activities such as agriculture (Heldwein et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

“…In addition to the synoptic-scale forcing, there is strong evidence that effects associated with the local topography in the central region of RS enhance the VNOR winds in Santa Maria and vicinities (Sartori, 2003;Stefanello et al, 2020;Sartori, 2016). Despite being an important regional weather system for RS state, the characteristics of the VNOR phenomenon have been little studied and documented (Sartori, 2003;Anabor et al, 2005;Stefanello et al, 2020;Arbage et al, 2008;Sartori, 2016;.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Meteorological Observations of the Vento Norte Phenomenon in the Central Region of Rio Grande do Sul

Rosa

Stefanello

Nascimento

et al. 2021

Rev. bras. meteorol.

Self Cite

View full text Add to dashboard Cite

During the cold season, episodes of a windstorm known as Vento Norte (VNOR) are frequently observed in the city of Santa Maria, situated in the central region of Rio Grande do Sul (RS). The onset of this windstorm is characterized by strong gusts with northerly component which are accompanied by a sharp increase in temperature and abrupt drying. A methodology based on the observed behavior of the standard deviation of temperature during VNOR was successful in identifying the onset and demise of the windstorm. Additionally, the research shows the results of different micrometeorological variables during the event. Early morning and evening atmospheric profiles exhibit an elevated mixed layer over central RS in association with the strong VNOR winds, indicating the presence of mechanically-forced mixing during nighttime hours.

show abstract

Turbulent statistical characteristics associated to the north wind phenomenon in southern Brazil with application to turbulent diffusion

Cited by 13 publications

References 23 publications

Quasi-Experimental Determination of Turbulent Dispersion Parameters for Different Stability Conditions from a Tall Micrometeorological Tower

Quasi-Experimental Determination of Turbulent Dispersion Parameters for Different Stability Conditions from a Tall Micrometeorological Tower

Evapotranspiration of the Brazilian Pampa Biome: Seasonality and Influential Factors

Meteorological Observations of the Vento Norte Phenomenon in the Central Region of Rio Grande do Sul

Contact Info

Product

Resources

About