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Rebecca D. Adams-Selin and Richard H. Johnson

as additional increase in propagation speed. The factors result in a convective line bowing out over time. However, very little work has focused on the surface features, such as pressure and temperature anomalies, associated with bow echoes. This is primarily due to the lack of sufficiently dense observational datasets. The arrangement of these anomalies associated with larger squall-line MCSs is highly recognizable ( Fig. 1 ). A surface mesohigh, primarily hydrostatically induced by

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Qinglong You, Zhihong Jiang, G. W. K. Moore, Yuntao Bao, Lei Kong, and Shichang Kang

SRES A1B scenario during the next 100 years ( Kang et al. 2010 ; Liu et al. 2009 ; You et al. 2014 ). Previous studies have proposed that in mountainous regions like the TP, the variability in the surface pressure is related to surface temperature variability ( Moore 2012 ; Toumi et al. 1999 ). Based on the hydrostatic equation and assumes that the atmosphere is in hydrostatic balance, an increase in surface pressure in mountainous regions can be used as a proxy for both the regional surface and

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Seung-Jong Baek, Istvan Szunyogh, Brian R. Hunt, and Edward Ott

( Lorenz and Emanuel 1998 ). In the present paper, we use a more realistic setting to investigate the potential benefits of accounting for the bias in the surface pressure state variable with bias model II. To simulate the situation faced in numerical weather prediction, we use two forecast models at different resolutions and with different levels of sophistication in the physical parameterization packages: the simulated “true” atmospheric states are generated by integrating the 2004 version of the

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Cheng-Ku Yu and Chia-Lun Tsai

with a dip in surface pressure. Ushijima (1958) also reported a similar trend of pressure alterations, a clockwise shift in wind direction, and a general decrease (increase) in temperature (humidity) in connection with the passage of their studied TCRs. Hamuro et al. (1969) provided evidence of alternating negative and positive pressure perturbations produced as a group of TCRs passed by. In keeping with the findings from Hamuro et al. and the aforementioned observational studies, Anthes (1982

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Michael Schindelegger and Richard D. Ray

recent studies has dealt with the significant day-to-day features in the dynamics of the upper atmosphere, most of the pre-satellite-era research concerning solar tides has been confined to theoretical descriptions or to analyses of meteorological surface parameters, particularly of variations in the air pressure p . The local barometer exhibits strong semidiurnal oscillations S 2 = S 2 ( p ), peaking usually 2–3 h before noon (and midnight) with amplitudes that exceed 120 Pa in the tropics but

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Thomas Spengler, Joseph Egger, and Stephen T. Garner

1. Introduction Water vapor affects the hydrostatic pressure distribution in the atmosphere the same way as dry air. In particular, the surface pressure p s is where ρ = ρ d + ρ υ is the total density (subscripts d and υ denote dry and vapor, respectively) and g is the gravitational acceleration. How does the surface pressure react to the formation of rain drops and their downward motion? Drop formation subtracts mass from the moist air and adds it to the water phase while the

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Dustan M. Wheatley and David J. Stensrud

1. Introduction Surface pressure observations provide significant information on atmospheric features across a broad range of scales. On the synoptic scale, surface pressure observations define the location and intensity of cyclones and anticyclones, while on the mesoscale these observations define the location and intensity of convectively induced mesohighs and mesolows ( Fujita 1955 ). Temporal changes in surface pressure provide guidance on the movement and evolution of these large-scale and

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Curt Covey, Aiguo Dai, Dan Marsh, and Richard S. Lindzen

1. Introduction Atmospheric tides are important features of middle- and upper-atmosphere structure and circulation. At the surface, the tides are significant parts of the day–night variations in both climate observations and simulations ( Dai and Trenberth 2004 ; Woolnough et al. 2004 ). In the tropics—and in midlatitudes after baroclinic waves are removed from consideration—the primary observed day-to-night variation of surface pressure is a semidiurnal (twice a day) cycle despite the obvious

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Yanping Li, Ronald B. Smith, and Vanda Grubišić

1. Introduction Diurnal solar atmospheric tides are excited primarily by the absorption of solar radiation by water vapor in the troposphere and ozone in the stratosphere, as well as by the turbulent heat transfer near the ground ( Forbes and Garrett 1979 ). Tides can be easily detected in surface pressure observations. In a hydrostatic atmosphere, surface pressure variations result from the integral effect in the vertical direction of density and temperature perturbations above the ground. For

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Kohei Takatama and Niklas Schneider

1. Introduction Recent satellite observations revealed a ubiquitous imprint of the ocean mesoscale on the surface wind. Associated SST fluctuations impact boundary layer winds by air–sea heat exchanges that simultaneously change hydrostatic pressure gradients (pressure adjustment mechanism; Lindzen and Nigam 1987 ) and vertical mixing of momentum (vertical mixing mechanism; Wallace et al. 1989 ; Hayes et al. 1989 ). This “thermal effect” has been studied extensively [see reviews by Xie

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