Observations of coherent structures from a scanning lidar over an irrigated orchard

Cooper, D. I.; Eichinger, W. E.; Hof, Douglas E.; Seville-Jones, D.; Quick, R.C.; Tiee, J. J.

doi:10.1016/0168-1923(94)90005-1

Cited by 12 publications

(10 citation statements)

References 9 publications

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“…It is unclear to us why the Cooper et al (1994) data result in a value of fc three times smaller than the Raupach et al (1989) estimate, but it should be noted that the Raupach et al (1989) analysis assumes that the instabilities are derived from the strong concavity in the mean-longitudinal velocity profile at z = h, and no thermal disturbances are considered. Also, the measurements reported in Cooper et al (1994) were collected at heights larger than x/h. It was also suggested by Paw U et al (1992) that a dimensionless frequency, analogous to a Strouhal (St) Number (the ratio of the vibrational to the translational speeds), be defined by f,h/ (UI ) .…”

mentioning

confidence: 65%

“…Using linearized perturbation analysis on the inviscid two-dimensional momentum equations of a laminar plane shear flow subjected to a velocity profile with an inflection point at z = h, Raupach et al (1989) found that fc is close to 0.1 (Ui)/h, while data from Paw U et al (1992) suggest that the Raupach et al (1989) analysis is only valid for rougher canopies and breaks down for (Ul)/h > 0.2. From the Cooper et al (1994) solar-blind water Raman lidar measurements above well irrigated Green Ash shade ornamental trees, we estimated fc = O.O35(Ul)/h (see Eichenger et al, 1992Eichenger et al, , 1993 for lidar details), which is smaller than the estimates of Raupach et al (1989) and Paw U et al (1992). It is unclear to us why the Cooper et al (1994) data result in a value of fc three times smaller than the Raupach et al (1989) estimate, but it should be noted that the Raupach et al (1989) analysis assumes that the instabilities are derived from the strong concavity in the mean-longitudinal velocity profile at z = h, and no thermal disturbances are considered.…”

mentioning

confidence: 99%

“…From the Cooper et al (1994) solar-blind water Raman lidar measurements above well irrigated Green Ash shade ornamental trees, we estimated fc = O.O35(Ul)/h (see Eichenger et al, 1992Eichenger et al, , 1993 for lidar details), which is smaller than the estimates of Raupach et al (1989) and Paw U et al (1992). It is unclear to us why the Cooper et al (1994) data result in a value of fc three times smaller than the Raupach et al (1989) estimate, but it should be noted that the Raupach et al (1989) analysis assumes that the instabilities are derived from the strong concavity in the mean-longitudinal velocity profile at z = h, and no thermal disturbances are considered. Also, the measurements reported in Cooper et al (1994) were collected at heights larger than x/h.…”

mentioning

confidence: 99%

“…It was also suggested by Paw U et al (1992) that a dimensionless frequency, analogous to a Strouhal (St) Number (the ratio of the vibrational to the translational speeds), be defined by f,h/ (UI ) . H ence, the Raupach et al (1989) analysis and the Cooper et al (1994) data yield St = 0.1 and 0.035, respectively.…”

mentioning

confidence: 99%

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Latent and sensible heat flux predictions from a uniform pine forest using surface renewal and flux variance methods

Katul

Hsieh

Oren

et al. 1996

Boundary-Layer Meteorol

105

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A surface renewal model that links organized eddy motion to the latent and sensible heat fluxes is tested with eddy correlation measurements carried out in a 13 m tall uniform Loblolly pine plantation in Duke Forest, Durham, North Carolina. The surface renewal model is based on the occurance of ramp-like patterns in the scalar concentration measurements. To extract such ramp-like patterns from Eulerian scalar concentration measurements, a newly proposed time-frequency filtering scheme is developed and tested. The time-domain filtering is carried out using compactly-supported orthononnal wavelets in conjunction with the "Universal Wavelet Thresholding" approach of Donoho and Johnstone, while the frequency filtering is carried out by a band-pass sine filter centered around the ramp-occurrence frequency as proposed by other studies. The method was separately tested for heat and water vapour with good agreement between eddy correlation flux measurements and model predictions. The usefulness of the flux-variance method to predict sensible and latent heat fluxes is also considered. Our measurements suggest that the simple flux-variance method reproduces the measured heat and momentum fluxes despite the fact that the variances were measured within the roughness sublayer and not in the surface layer. Central to the predictions of water vapour fluxes using the flux-variance approach is the similarity between heat and water vapour transport by the turbulent air flow. This assumption is also investigated for this uniform forest terrain.

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confidence: 65%

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confidence: 99%

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confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Latent and sensible heat flux predictions from a uniform pine forest using surface renewal and flux variance methods

Katul

Hsieh

Oren

et al. 1996

Boundary-Layer Meteorol

105

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“…This technology provides a unique way to describe atmospheric boundary layer (ABL) phenomena (e.g., Eloranta and Fome~1992; Cooper et al, 1994). The Iidar system wed here is a sed.f%mtained field-deployable UV Raman water-vapor Mar (Eichinger et al, 1994) built at the Los Alamos National Laboratory (LAW) and based on the technique pioneered by Melfi et al (1969).…”

Section: Introductionmentioning

confidence: 99%

Probing near-surface atmospheric turbulence with lidar measurements and high-resolution hydrodynamic models

et al. 2001

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Los Alamos National Laboratory, an affirmative actiorkqual oppmb.mityemplo yer, is operated by the University of Califomiaforthe U.S. Deparlrnent of Energy under mntract W-7405-ENG-36. By acceptance of this artkle, the publisher rewgnizesthatthe U.S. Government retains a nonexclusive, royallyfree license to publish or reproduce the published form of this mntribution, or to allow otherato do so, for U.S. Government purposes. Los Alamos National Laboratory requests that the publisher identify this article as work performed under the auspices of the U.S. Department of Energy. Los Alamos National Laboratov strongly supporta academic freedom and a researcher's right to publisk as an institution, however, the Laboratory does not endorse the viewpoint of a publication or guarantee its technical correctness. ABSTRACT DEC 132000As lidar technology is able to provide fast data collection at a resolution of meters in an atmospheric WHl!l volume, it is imperative to promote a modeling counterpart of the Iidar capability This paper describes an integrated apability based on data fi-oma scanning water vapor Ii&r and a high-resolution hydrodynamic m,odel (HIGRAD) equipped with a visuali=tion routine (VLEWER) that simulates the Mar scanning. The purpose is to better un&rstand the spatial and temporal representativeness of the Mar measurements and, in tu~to extend their utility in studying turbulence fields in the atmospheric boundary layer. Raman Iidar water vapor data collected over the Pacific warm pool and the simulations with the HIGRAD code are used for identifying the underlying physics and potential aliasing effects of spatially resolved lidar measurements. This capability also helps improve the trade-off between spatial-temporal resolution and coverage of the Iidar measurements.

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Windblown trees as a palaeoclimate indicator: the character and role of gusts

Allen¹

1996

Palaeogeography, Palaeoclimatology, Palaeoecology

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Observations of coherent structures from a scanning lidar over an irrigated orchard

Cited by 12 publications

References 9 publications

Latent and sensible heat flux predictions from a uniform pine forest using surface renewal and flux variance methods

Latent and sensible heat flux predictions from a uniform pine forest using surface renewal and flux variance methods

Probing near-surface atmospheric turbulence with lidar measurements and high-resolution hydrodynamic models

Windblown trees as a palaeoclimate indicator: the character and role of gusts

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