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Paul M. Barker, Jeff R. Dunn, Catia M. Domingues, and Susan E. Wijffels

Falmouth Scientific Instruments (FSI) sensor package deployed by Woods Hole Oceanographic Institution (WHOI), instrument type 852]. More recently, some studies suggested that there may be a more widespread negative bias in Argo pressure measurements ( Uchida et al. 2008 ; Uchida and Imawaki 2008 ). A uniform depth error of 5 dbar globally produces a temperature bias that is greater than the observed ocean warming during the past 50 yr in the tropical and subtropical ocean and equals almost half of the

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John A. Knaff and Raymond M. Zehr

1. Introduction Possibly the most accurate and reliable measure of tropical cyclone (TC) intensity is the minimum sea level pressure (MSLP) either estimated from aircraft reconnaissance flight level or obtained via direct observation (surface or dropwindsonde). However, the destructive potential of TCs is better related to the maximum wind speed at or near the surface. For this reason, TC forecasts and advisories as well as climatological records are most useful when they describe TC intensity

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Dan Liberzon and Lev Shemer

1. Introduction Static pressure fluctuations play an important role in momentum balance in turbulent boundary layer flows. In particular, fluctuations of static pressure in airflow over the water surface may contribute significantly to generation of water waves by wind ( Jeffreys 1925 ; Phillips 1957 ). However, measurements of the static pressure fluctuations within the turbulent airflow boundary layer above water waves are not trivial, because they require decoupling of static pressure

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Hui Wan, Xiaolan L. Wang, and Val R. Swail

simulations. It is imperative to conduct quality assurance and homogenization of climate data before these data are used for various climate studies, especially climate change–related studies. Atmospheric circulation plays an essential role in the climate system because of its effects on the distribution of heat and moisture over the globe. Surface atmospheric pressure is an important variable that describes atmospheric circulation. Variations in surface pressure should also reflect variations in surface

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Shyamnath Veerasamy

1. Introduction Knaff and Zehr (2007 , hereinafter KZ07 ) presented some very interesting and important results from their study of the wind–pressure relationship (WPR) that exists in tropical cyclones (TCs). In the southwest Indian Ocean (SWIO), analysis of TC is carried out by using the Dvorak technique (1984), which, because of the severe lack of data, is the only tool available for operational use. I would like to comment on the Dvorak WPR (D-WPR) in use in the SWIO and the term

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J. N. Moum and J. D. Nash

1. Introduction Highly resolved and rapidly sampled measurements of velocity from a fixed position on the seafloor over Oregon’s continental shelf led to a prediction of the form, sign, and magnitude of the pressure signature of nonlinear internal waves of elevation ( Moum and Smyth 2006 ). The competing effects of internal hydrostatic pressure (>0 for elevation waves), external hydrostatic pressure, and nonhydrostatic pressure (both <0 for elevation waves) led to a predicted positive seafloor

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Joseph Egger and Klaus-Peter Hoinka

friction torques are the main torques to be included if height and isobaric coordinates are used in the analysis. They act at the earth’s surface. If, however, isentropic coordinates are chosen, there are vertical fluxes due to the heating but also internal atmospheric torques, the pressure torques, which are important. While the atmospheric “response” to mountain and friction torques attracted much attention, there was so far little interest in the isentropic pressure torques (see Egger et al. 2007

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Chanh Q. Kieu, Hua Chen, and Da-Lin Zhang

1. Introduction The relationship between the tropical cyclone (TC) maximum surface wind (VMAX) and minimum sea level pressure (PMIN) plays an important role in the assessment and documentation of TC activities (e.g., Koba et al. 1990 ; Harper 2002 ; Kossin and Velden 2004 ; Knaff and Zehr 2007 , hereafter KZ07 ; Holland 2008 , hereafter H08 ). Given one variable such as PMIN or VMAX, an appropriate pressure–wind relationship (PWR) could provide information about the other variable

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Greg Holland

1. Introduction A wide variety of relationships has been proposed for relating the minimum central pressure and maximum surface winds in tropical cyclones (see Harper 2002 for a complete summary). 1 The relationships provide a critical analysis tool for the assessment of maximum winds from a diverse set of observations and estimates, particularly in regions that have relied largely on the Dvorak satellite interpretation ( Dvorak 1975 , 1984 ) for assessing maximum intensity since the mid

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Christopher D. Karstens, Timothy M. Samaras, Bruce D. Lee, William A. Gallus Jr., and Catherine A. Finley

1. Introduction Several efforts have been made to acquire and interpret near-ground pressure and wind measurements in or near a tornado. These efforts are motivated by the desire to understand the complex and violent nature of a tornado’s interaction with the surface. The earliest examinations of tornado measurements were conducted on serendipitous tornado or near-tornado encounters with statically positioned weather stations or barometers (e.g., Tepper and Eggert 1956 ; Fujita 1958 ; Ward

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