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Temple R. Lee
and
Tilden P. Meyers

–Obukhov length scale defined as (2) L = − θ ¯ υ u * 3 κ g w ′ θ υ ′ ¯ . In Eq. (2) , θ υ is the virtual potential temperature, u ∗ is the friction velocity, κ is the Von Kármán constant, g is the gravitational acceleration, and w ′ θ υ ′ ¯ is the kinematic heat flux. MOST is also used as the basis for scaling surface-layer turbulence quantities. Many different scaling relationships have been proposed that nondimensionalize the standard deviations in the wind components by dividing these

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Rod Frehlich
,
Robert Sharman
,
Charles Clough
,
Michael Padovani
,
Kelly Fling
,
Ward Boughers
, and
W. Scott Walton

points of the projectile is more difficult to assess. A technique for estimating the magnitude of the statistical variations of ballistic trajectories due to atmospheric turbulence along the path of the projectile is provided in this paper. These estimates can be used to bound the scatter due to atmospheric processes, and they allow more meaningful interpretations of measured scatter during ballistics testing. These estimates together with suitable measurements can also be used to identify low

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Richard M. Eckman
,
Ronald J. Dobosy
,
David L. Auble
,
Thomas W. Strong
, and
Timothy L. Crawford

( Miller 1964 ; Tuleya 1994 ). Atmospheric turbulence also plays an important role in property losses associated with tropical cyclones. Structural engineering design is often based on gust factors ( Krayer and Marshall 1992 ; Powell et al. 1996 ; Paulsen and Schroeder 2005 ), which are ratios of the peak wind speed based on a short averaging time (e.g., 2 s) to the mean wind speed based on a longer averaging time (e.g., 10 min). These gust factors are directly related to the velocity power spectra

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William D. Smyth
and
Barry Ruddick

). While interleaving signals are often of large amplitude and therefore demand a nonlinear theoretical treatment (e.g., Walsh and Ruddick 1998 ; Mueller et al. 2007 ), linear perturbation theory provides an essential starting point for defining spatial and temporal scales and for identifying the central mechanisms (e.g., Stern 1967 ; May and Kelley 1997 ; Walsh and Ruddick 2000 ; Smyth 2007 ). Here, we use linear analysis to explore the role of ambient turbulence in interleaving driven by salt

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Jeremy D. Bricker
and
Stephen G. Monismith

1. Introduction Pointwise velocimeters allow us to determine benthic and water column shear stresses via the direct calculation of Reynolds stresses from fluctuating velocities. However, because variance associated with waves is often much larger than that associated with turbulence, some form of wave–turbulence decomposition must be used ( Jiang and Street 1991 ; Thais and Magnaudet 1995 ; Trowbridge 1998 ). In a flow with both waves and currents, the instantaneous horizontal velocity u

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Jung-Hoon Kim
and
Hye-Yeong Chun

1. Introduction Turbulence at aircraft scale (10–1000 m) or that directly affects aircraft is commonly referred to as aviation turbulence ( Lester 1994 ). Aviation turbulence in the free atmosphere is a serious concern in the general aviation industry because it frequently causes occupant injuries, flight delays, fuel losses, and structural damage. It is more dangerous when it occurs unexpectedly at cruising levels, where most of the passengers and crew are unbuckled. According to the 2009

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Ronald Dobosy
,
Edward J. Dumas
,
David L. Senn
,
Bruce Baker
,
David S. Sayres
,
Mark F. Witinski
,
Claire Healy
,
Jason Munster
, and
James G. Anderson

1. Introduction The Best Aircraft Turbulence (BAT) probe was developed explicitly for environmental research from small aircraft ( Crawford and Dobosy 1992 , hereafter CD92 ). The pressure distribution over a sphere had been found among multiple alternatives to be the most effective measure of flow relative to an airplane ( Brown et al. 1983 ). Major research centers developed airborne systems capable of accurate turbulence measurements ( Lenschow 1986 ; MacPherson et al. 1992 ; LeMone et al

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Xiang-Yu Li
,
Axel Brandenburg
,
Gunilla Svensson
,
Nils E. L. Haugen
,
Bernhard Mehlig
, and
Igor Rogachevskii

). The most notorious difficulty is how turbulence affects the collisional growth. This problem has a long history and was recently reviewed by Shaw (2003) , Devenish et al. (2012) , Grabowski and Wang (2013) , and Pumir and Wilkinson (2016) . The pioneering work by Saffman and Turner (1956) proposed a theoretical model for the collision rate (Saffman–Turner model) of cloud droplets. The key idea of the Saffman–Turner model is that the collision rate is dominated by small scales of turbulence

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J. K. Wolff
and
R. D. Sharman

1. Introduction Turbulence in the free atmosphere remains a major concern for aircraft operations, causing flight delays and occupant injuries and fatalities, which, when combined, lead to economic losses typically worth millions of dollars annually. Further, turbulence is a major dissipative mechanism in the atmospheric energy budget and must be understood to develop realistic parameterizations for numerical weather prediction (NWP) and general circulation models (GCMs). Yet the mechanisms

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S. A. Thorpe
,
J. A. M. Green
,
J. H. Simpson
,
T. R. Osborn
, and
W. A. M. Nimmo Smith

dissipation. We describe a similar deployment of ARIES II in a weakly stratified region of the Irish Sea at times when boils are observed, when nearby there are vertical profiles of turbulent dissipation rates made using Fast Light Yo-yo (FLY) profiler casts, and when horizontal sections of turbulent dissipation are made by sensors mounted on the Autonomous Underwater Vehicle (AUV) Autosub ( Thorpe et al. 2003 ). Our purpose is to describe the new findings about boils and the related turbulence. Although

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