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Aleksi Nummelin, Stephen Jeffress, and Thomas Haine

1. Introduction Sea surface temperature (SST) varies at different time and space scales, and these variations have been linked to the variability in several climate and environmental phenomena ( Deser et al. 2010 ). In addition, the SST data provide valuable information on surface ocean kinematics as it is observed at high spatial and temporal resolution. It is therefore of interest to characterize SST variability and to use the SST data to characterize ocean kinematics. To this end we develop

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Jessica M. Kleiss and W. Kendall Melville

kinematics of the breaking waves would be useful for a more detailed description of wave energy dissipation, momentum, and gas transfer. In 1985, Phillips proposed a statistical measure of wave breaking, Λ( c ), such that Λ( c ) d c is the average total length per unit sea surface area of breaking fronts that have velocities in the range of c to c + d c . In the following discussion, c = ( c , θ ) is the breaking velocity, with magnitude c and direction θ . It follows that the distribution

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David Farmer, Li Ding, Donald Booth, and Martin Lohmann

studies, it is a quite specific type of information that can only be converted into other variables such as flow velocity near the surface under certain assumptions. The validity of these assumptions may be open to question, especially in the case of large and steep waves. Here we describe an approach to the measurement of wave kinematics that exploits a bistatic Doppler sonar mounted on the seafloor. The present work grew out of a practical need to measure flow speeds in extreme waves relevant to

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Samuel R. Webb, Nigel T. Penna, Peter J. Clarke, Stuart Webster, Ian Martin, and Gemma V. Bennitt

operationally provide PWV observations for assimilation into NWP models in near–real time ( Gutman et al. 2004 ). These observations complement more traditional sources of atmospheric water vapor measurements such as radiosondes, which suffer from poor spatial and temporal resolution. GPS PWV measurements may be obtained as often as once every 5–15 min, while the spatial resolution is governed solely by the number of receivers deployed. The use of GPS in network real-time kinematic applications (e

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Catherine A. Carlson and Gregory S. Forbes

OCTOBER 1989 CATHERINE A. CARLSON AND GREGORY S. FORBES 769A Case Study Using Kinematic Quantities Derived from a Triangle of VHF Doppler Wind Profilers CATHERINE A. CARLSONNASA/Marshall Space Flight Center, Huntsville, Alabama GREGORY S. FORBESDepartment of Meteorology, Pennsylvania State University, University Park, Pennsylvania(Manuscript received 30 May 1988, in final form 22 March 1989

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A. Protat, Y. Lemaitre, and G. Scialom

of these VAD-like analyses, compared to the methods devoted to the three-dimensional wind field retrieval from ground-based radar data, results from the fact that they process a great amount of data in the mesoscale area sampled by the radar, leading to a very good accuracy of the diagnosed kinematic parameters, in particular the vertical air velocity (accurate to within 10 cm s −1 ) at mesoscale. However, ground-based Doppler radars do not allow a global description of precipitating systems or a

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G. Scialom, A. Protat, and Y. Lemaître

other crucial kinematic parameters mentioned previously. Moreover, in the DAVAD approach, the vertical profiles of horizontal divergence, mean vertical velocity and vertical vorticity are retrieved simultaneously through a linear regression allowing a separation of these three parameters, as specified in section 2b(1) . No assumption is thus needed for the value of the hydrometeor fall speed. In section 2 of the present paper, the principle and mathematical formulation of the DAVAD analysis are

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K. E. Steele

al. (1978) have shown that spectral density values can be noticeably altered by Doppler frequency changes alone, independent of energy exchange effects that may occur when the current vector field is not constant in space and time. This paper is concerned only with kinematic effects; physical wave–current interactions, about which others ( Phillips 1977 ) have written, are ignored. In a large current-free open ocean area, over which a constant wind has been blowing for many hours, the

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T. Connor Nelson, Lee Harrison, and Kristen L. Corbosiero

results of Gentry and Lackmann (2010) , however, show that increased model resolution down to 2-km grid spacing or less is required to understand TC eyewall kinematics and physics. These results suggest that observations should also be taken at high resolution. The likelihood of highly correlated data points increases, however, with the increase in horizontal or vertical resolution and should approach unity ( Brett and Tuller 1991 ; Khalili et al. 2007 ). Conversely, if dropsondes are launched too

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Bruce W. Johnston, John D. Marwitz, and Richard E. Carbone

analysis of single-Doppler radar data called band-velocity-processing (BVP) is presented.The BVP m~thod was designed to exploit the two-dimensional nature of banded precipitation systems withcrossband length scales of 5-50 kin. The BVP method offers improved horizontal (crossband) resolution overexisting volume scan methods (VAD/VVP), plus the ability to extract band-perpendicular vertical cross sectionsfrom a single volume scan. The BVP analysis yields a more complete kinematic structure than RHI

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