### Abstract

A detailed accuracy analysis is presented for moments, up to order four, of both velocity (horizontal u and vertical w) and scalar (temperature θ and humidity q) fluctuations, as well as of the products uw, wθ and wq, in the atmospheric surface layer. The high-order moments and integral time scales required for this analysis are evaluated from data obtained at a height of about 5 m above the ocean surface under stability conditions corresponding to Z/L \- -0.05. Measured moments and probability density functions of some of the individual fluctuations show departures from Gaussianity, but these are sufficiently small to enable good estimates to be obtained using Gaussian instead of measured moments. For the products, the assumption of joint Gaussianity for individual fluctuations provides a reasonable, though somewhat conservative, estimate for the integration times required. The concept of Reynolds number similarity implies that differences in integration time requirements for flows at different Reynolds numbers arise exclusively from differences in integral time scales. A first approximation to the integral time scales relevant to atmospheric flows is presented.

Original language | English (US) |
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Pages (from-to) | 341-359 |

Number of pages | 19 |

Journal | Boundary-Layer Meteorology |

Volume | 14 |

Issue number | 3 |

DOIs | |

State | Published - May 1978 |

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### ASJC Scopus subject areas

- Atmospheric Science

### Cite this

*Boundary-Layer Meteorology*,

*14*(3), 341-359. https://doi.org/10.1007/BF00121044

**Accuracy of moments of velocity and scalar fluctuations in the atmospheric surface layer.** / Sreenivasan, K. R.; Chambers, A. J.; Antonia, R. A.

Research output: Contribution to journal › Article

*Boundary-Layer Meteorology*, vol. 14, no. 3, pp. 341-359. https://doi.org/10.1007/BF00121044

}

TY - JOUR

T1 - Accuracy of moments of velocity and scalar fluctuations in the atmospheric surface layer

AU - Sreenivasan, K. R.

AU - Chambers, A. J.

AU - Antonia, R. A.

PY - 1978/5

Y1 - 1978/5

N2 - A detailed accuracy analysis is presented for moments, up to order four, of both velocity (horizontal u and vertical w) and scalar (temperature θ and humidity q) fluctuations, as well as of the products uw, wθ and wq, in the atmospheric surface layer. The high-order moments and integral time scales required for this analysis are evaluated from data obtained at a height of about 5 m above the ocean surface under stability conditions corresponding to Z/L \- -0.05. Measured moments and probability density functions of some of the individual fluctuations show departures from Gaussianity, but these are sufficiently small to enable good estimates to be obtained using Gaussian instead of measured moments. For the products, the assumption of joint Gaussianity for individual fluctuations provides a reasonable, though somewhat conservative, estimate for the integration times required. The concept of Reynolds number similarity implies that differences in integration time requirements for flows at different Reynolds numbers arise exclusively from differences in integral time scales. A first approximation to the integral time scales relevant to atmospheric flows is presented.

AB - A detailed accuracy analysis is presented for moments, up to order four, of both velocity (horizontal u and vertical w) and scalar (temperature θ and humidity q) fluctuations, as well as of the products uw, wθ and wq, in the atmospheric surface layer. The high-order moments and integral time scales required for this analysis are evaluated from data obtained at a height of about 5 m above the ocean surface under stability conditions corresponding to Z/L \- -0.05. Measured moments and probability density functions of some of the individual fluctuations show departures from Gaussianity, but these are sufficiently small to enable good estimates to be obtained using Gaussian instead of measured moments. For the products, the assumption of joint Gaussianity for individual fluctuations provides a reasonable, though somewhat conservative, estimate for the integration times required. The concept of Reynolds number similarity implies that differences in integration time requirements for flows at different Reynolds numbers arise exclusively from differences in integral time scales. A first approximation to the integral time scales relevant to atmospheric flows is presented.

UR - http://www.scopus.com/inward/record.url?scp=0001049334&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001049334&partnerID=8YFLogxK

U2 - 10.1007/BF00121044

DO - 10.1007/BF00121044

M3 - Article

AN - SCOPUS:0001049334

VL - 14

SP - 341

EP - 359

JO - Boundary-Layer Meteorology

JF - Boundary-Layer Meteorology

SN - 0006-8314

IS - 3

ER -