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Christopher E. Doughty, Scott R. Loarie, and Christopher B. Field

South America in the present day is deforestation-associated land-use change and the drainage of wetlands ( Loarie et al. 2011 ). Deforestation modifies not only albedo but other important climate-driving variables as well, such as canopy height and rooting profile, which will affect surface roughness and evapotranspiration. Most studies conclude albedo dominates surface energy budgets during land-use change ( Berbert and Costa 2003 ), but other studies have found a large role for an

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William M. Drennan, Peter K. Taylor, and Margaret J. Yelland

. Vested , and S. E. Larsen , 1998 : On the dependence of sea surface roughness on wind waves. J. Phys. Oceanogr. , 28 , 1702 – 1716 . Kitaigorodskii , S. A. , and Y. A. Volkov , 1965 : On the roughness parameter of the sea surface and the calculation of momentum flux in the near-water layer of the atmosphere. Izv. Atmos. Oceanic Phys. , 1 , 973 – 988 . Krogstad , H. E. , J. Wolf , S. P. Thompson , and L. R. Wyatt , 1999 : Methods for intercomparison of wave measurements

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Elie Bou-Zeid, Marc B. Parlange, and Charles Meneveau

flux over variable surfaces that appear statistically homogeneous at the regional scale ( Kustas and Brutsaert 1986 ; Parlange and Brutsaert 1989 , 1993 ; Sugita and Brutsaert 1990 , 1992 ). For momentum flux computations at regional scales, an effective regional surface roughness ( z o , e ) can be obtained from the log-law based on wind profiles measured under a near-neutral atmospheric stability: where κ = 0.4 is the von Kármán constant, 〈 u 〉 is the time-averaged streamwise velocity, u

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Paul A. Hwang

1. Introduction Small-scale surface waves serve as the roughness elements that affect the propagation and scattering of optical waves and microwaves at the ocean surface. For Ku- and X-band radars, the resonant wavelengths are a few centimeters. These short waves are easily generated by wind and modified by surface currents from all sources. They serve as natural tracers for remote sensing of oceanographic processes. For example, remote sensing of internal and surface waves is based primarily

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Daniel B. Kirk-Davidoff and David W. Keith

1. Introduction The impact of topography on synoptic- and planetary-scale atmospheric motions has been studied carefully in a variety of modeling contexts (e.g., Hoskins 1983 ; Cook and Held 1992 ; Schär and Smith 1993 ; Grubišić et al. 1995 ; Richter and Mechoso 2004 ). However, the effect of isolated roughness anomalies at the earth’s surface has received far less attention. The subject has attracted interest recently because of the very rapid expansion of wind turbine power generation

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P. A. Taylor

432 JOURNAL OF THE ATMOSPHERIC SCIENCES Vo~.u~m26The Planetary Boundary Layer above a Change/n Surface Roughness P. A. TAx~o~Dept. of Mathematics, University of Toronto, Canada(Manuscript received 19 August 1968, in revised form 22 December 1968) A mixing length model is used to relate the turbulent shear stress to the mean velocity field within theplanetary boundary layer above a

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Adrie F. G. Jacobs and Emile Schols

NOVEMBER 1986 ADRIE F. G. JACOBS AND EMILE SCHOLS 1577Surface Roughness Parameter Estimated with a Drag Technique ADRIE F. G. JACOBS AND EMILE SCHOLSDepartment of Physics and Meteorology, Agricultural University, 6701 AP Wageningen, The Netherlands(Manuscript received 26 September 1985, in final form 21 April 1986)ABSTRACT The surface roughness parameter, Zo, can be estimated with

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Mark A. Donelan, Fred W. Dobson, Stuart D. Smith, and Robert J. Anderson

SEPTEMBER 1993 NOTES AND CORRESPONDENCE 2143On the Dependence of Sea Surface Roughness on Wave Development MARK A. DONELANNational Water Research Institute, Canada Centre for Inland Waters, Burlington, Ontario, Canada FRED W. DOBSON, STUART D. SMITH, AND ROBERT J. ANDERSONDepartment of Fisheries and Oceans, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada14 August 1992 and

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Paul A. Hwang

1. Introduction The ocean surface roughness plays an important role in air–sea interaction. It is the major cause of wind drag, thus affecting the mass, momentum, and energy transfers across the air–sea interface. It is also an important topic in remote sensing of the ocean environment because the electromagnetic (EM) emission or scattering is modified by the surface roughness condition. The primary contribution of the ocean surface roughness is from surface waves with length scales much

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S. J. Jacobs

991~ JOURNAL OF PHYSICAL OCEANO(RAPHY VOI.UME19Effective Roughness Length for Turbulent Flow over a Wavy Surface S. I. JACOBSDepartment of Atmospheric, Oceanic, and Space Sciences and Deganment of Mechanical Engineering and Applied Mechanics, The University of Michigan, Ann Arbor, Michigan (Manuseript received 16 Apr~ 1987, in final form 23 November 1988 A two-equation turbulence

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