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A. E. E. Rogers, M. Lekberg, and P. Pratap

filters in the downconveter, is used for the ozone line. To minimize systematic effects, frequency switching is used to obtain a difference spectrum with the ozone line centered in the lower quarter band and then inverted in the center of the upper three-quarter band. Following an accumulation of 90 s, the upper-half-band spectrum is subtracted from the lower-half-band spectrum and a 625-kHz band centered on the ozone line is stored to disk for subsequent averaging. The theoretical noise in the

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Valentin Louf, Olivier Pujol, and Henri Sauvageot

frequently observed with coastal radars ( Brooks et al. 1999 ; Bech et al. 2000 ; Atkinson and Zhu 2006 ; Mesnard and Sauvageot 2010 ; Haack et al. 2010 ; Chang and Lin 2011 ). Recently, Ding et al. (2013) have observed ducting at the periphery of a tropical cyclone over the western North Pacific Ocean. Concerning continental areas, there are few AP studies. Using a 16-yr record of operational sounding data, Steiner and Smith (2002) presented a seasonal climatology of the various regimes of

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Jenny A. U. Nilsson, Peter Sigray, and Robert H. Tyler

magnetic field and the observed potential difference. For periods longer than 24 h the coherence was low, indicating that the ionospheric influence was negligible, and thus the low-pass cutoff frequency was set to 30 h. Since an earlier study by Pizarro and Shaffer (1998) showed that baroclinic fluctuations mainly manifest themselves on multiweekly time scales, a high-pass filter with a 2-week cutoff was applied to reduce baroclinic effects. A bandpass filter was constructed by combining low- and

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Timothy A. Bonin, Brian J. Carroll, R. Michael Hardesty, W. Alan Brewer, Kristian Hajny, Olivia E. Salmon, and Paul B. Shepson

was removed for the PPI scans and stares. This is done by applying a structure function fit to the autocovariance of w in the time series and residuals of the VAD fit along a range bin around the PPI, similarly to the technique described by Lenschow et al. (2000) . In addition to removing instrument noise, this structure function fit corrects for averaging effects over the pulse volume and accumulation time ( Bonin et al. 2016 ). With this noise removal technique, it is assumed that the lower

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T. S. Hudson, A. Horseman, and J. Sugier

, since it provides a consistent foundation for the comparison of diurnal, seasonal, and solar cycle variations of virtual ionosphere height and the related effects upon interference minima positions for a lightning detection system, something that has not previously been undertaken. Further to this, a VLF propagation model has now been developed, and is briefly detailed in this paper, that provides additional insight into the location of these minima and can be used to estimate the ionosphere height

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Lindsey M. Richardson, W. David Zittel, Robert R. Lee, Valery M. Melnikov, Richard L. Ice, and Jeffrey G. Cunningham

the existing rain and snow methods. Section 3 compares the seasonal, spatial, and temporal availability of Z DR bias estimates from CABS from the original algorithm in the 1700–1900 UTC window (2-h version) to a modified continuous monitoring version of the algorithm. Section 4 concludes with a summary and discussion. 2. Z DR bias estimation from external targets a. Light rain and dry snow overview To assess the Z DR bias from an operational system that cannot point vertically due to

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Fernando J. Méndez, Melisa Menéndez, Alberto Luceño, and Inigo J. Losada

( t ), and ξ ( t ) can contain sine waves representing seasonal effects (see, e.g., Katz et al. 2002 ), linear and/or exponential terms representing long-term trends, and covariates representing environmental processes (e.g., El Niño), among others. We will analyze the performance of the MMS method throughout the paper. In the following, the procedures to estimate the parameters and the quantiles as well as to calculate the confidence intervals are shown. Criteria for model diagnostic and

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Rui M. Ponte

has good estimates of P a (range of variability in ρg factor is only a few percent and can be neglected). The importance of accounting for low-frequency effects of η ib in sea level data analysis has been long recognized, particularly for the seasonal cycle ( Patullo et al. 1955 ; Rossiter 1962 ), but the lack of P a records collocated with the measurements or uncertainties in the available P a fields can be a problem. In recent years, multidecadal P a fields have become available

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Koichiro Wakasugi, Akiyoshi Mizutani, Masaru Matsuo, Shoichiro Fukao, and Susumu Kato

, especially the effects of spectral broadening mechanisms, the method is appliedto Doppler spectra obtained during the seasonal rain front (Bai-u front) observation in Japan. Variations ofvertical air velocity and distribution parameters are discussed, based on this longer period dataset.1. Introduction In measuring the raindrop size distribution N(D) andmean vertical air velocity ~, Wakasugi et at. (1986)proposed the use of vertically pointing VHF Dopplerradars to examine the bimodal echo spectrum

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Ying-Po Liao and James M. Kaihatu

studies. In particular, Orzech et al. (2014) employed SWAN for the proposed assimilation algorithms, and furthermore generated sensitivity maps to show the dependence of bathymetric resolution of special statistics. The purpose of this study is to understand the effects of bathymetrically controlled processes, such as depth-induced breaking and refraction, on the seasonal characteristics of the wave climate in the Persian Gulf, with particular focus on the coastal areas of Qatar. A 5-yr wave

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