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Chih-Pei Chang, Mong-Ming Lu, and Hock Lim

northwestern Pacific (area A in Fig. 6-3 ), which causes the deep convection east of Vietnam and the Philippines in boreal fall ( Fig. 6-2 ). The convection in these areas is much stronger than in both boreal summer and winter, even though during boreal winter the northeasterly winds are stronger. This is because the colder and drier air and the colder sea surface temperature (SST) make deep convection less likely to develop north of 10°N, so that strong winter cold surges actually produce drying

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Guoxiong Wu and Yimin Liu

blocks cold outbreaks from the north and confines the winter monsoon to eastern and southern Asia ( Chang et al. 2006 ). Yanai and Wu (2006) gave a thorough review of the past studies about the effects of the TP. The review starts from the research in the 1950s on the jet stream and the warm South Asian high, and the early progress of TP research. The review then goes over studies concerning the mechanical effects of the TP on large-scale motion, the winter cold surge, and the summer negative

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Ronald B. Smith

by relatively high pressure there. Until the flow has stagnated, the center streamline cannot split left and right. The high pressure on the windward slope is caused by an elevated region of lifted dense cold air aloft, directly over the windward slopes. The forward tilt of the lifted air is associated with the generation of a vertically propagating mountain waves ( section 6 ). Using typical values of N = 0.01 s −1 and U = 10 m s −1 , mountain heights of 100, 1000, and 10 000 m give the

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Kerry Emanuel

with altitude, and the inference that air in the eye is descending. He even shows a slight cold anomaly at the storm center in the lower stratosphere, a feature seen in recent observations by very-high-altitude aircraft and in some numerical simulations. Fig . 15-2. Cross section through a hurricane. The abscissa is radial distance from storm center (km), and the ordinate is pressure (hPa; right). Solid curves show potential temperature (K; left), and dashed curves show temperature (C), with the

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Robert A. Houze Jr.

accompanying the line of storms ahead of a front as the result of a gravity wave being triggered at the cold front and moving out ahead of the front. We now know that this pressure rise is mainly associated with the spreading downdraft cold pool of the storms, and that deep convective clouds breaking out by the release of instability in the warm sector air ahead of a cold front tend to arrange themselves in lines ahead of an approaching cold front for a variety of synoptic and mesoscale reasons that would

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David A. R. Kristovich, Eugene Takle, George S. Young, and Ashish Sharma

not surprising that a similar array of surface-flux-driven mesoscale atmospheric responses arise. Simple mixed-layer models of this process revealed that cold-air advection across the sharp oceanic temperature front of a western boundary current results in enhanced surface fluxes of heat and moisture and the consequent downstream warming, moistening, and deepening of the atmospheric boundary layer. Similarly, mesoscale modeling of cold-air outbreaks ( Sun and Hsu 1988 ) revealed that ABL

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David M. Schultz, Lance F. Bosart, Brian A. Colle, Huw C. Davies, Christopher Dearden, Daniel Keyser, Olivia Martius, Paul J. Roebber, W. James Steenburgh, Hans Volkert, and Andrew C. Winters

, stratified air masses on the cold side of coastal fronts proved to be effective in providing wave ducts for the passage of long-lived, large-amplitude mesoscale inertia–gravity waves (e.g., Bosart and Sanders 1986 ; Uccellini and Koch 1987 ; Bosart and Seimon 1988 ; Bosart et al. 1998 ). An excellent example of a long-lived, large-amplitude mesoscale inertia–gravity wave and “snow bomb” associated with a strong Atlantic coastal cyclone occurred on 4 January 1994 ( Bosart et al. 1998 ) ( Fig. 16

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Sue Ellen Haupt, Robert M. Rauber, Bruce Carmichael, Jason C. Knievel, and James L. Cogan

signatures of cold fronts ( Giles 1987 ). In the Korean War, simple visual reconnaissance was judged consistently superior to operational forecasts of conditions needed for air cover, so in 1952 Bomber Command stopped using forecasts as a factor in assessing air cover during mission planning ( Fuller 1974 ). During mission planning, failure to communicate basic situational awareness of weather can have grave consequences. In April 1980 the infamously disastrous attempt to rescue the American hostages in

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Stanley G. Benjamin, John M. Brown, Gilbert Brunet, Peter Lynch, Kazuo Saito, and Thomas W. Schlatter

is a horizontal view of the distribution of air masses at the ground. The broken line is the boundary (polar front) at the ground between a warm current from the west-southwest (white arrows), displacing to the east a wedge of cold air (black arrows) returning northward from a brief sojourn in southern latitudes. Along the boundary of the receding cold air (warm front) the warm air rises, and its moisture condenses and produces a broad area of rain or snow (shaded area). The upper part of the

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Russ E. Davis, Lynne D. Talley, Dean Roemmich, W. Brechner Owens, Daniel L. Rudnick, John Toole, Robert Weller, Michael J. McPhaden, and John A. Barth

ways to measure the ocean along with the phenomena they have described: ships in section 2 ; moorings, Argo floats, and underwater gliders in sections 3 and 4 ; and moored velocity and air–sea flux measurements in sections 5 and 6 . Other sections address groups assembled to address the special ocean–atmosphere issues of specific regions. For example, section 7 discusses El Niño–Southern Oscillation (ENSO) and the Tropical Ocean and Global Atmosphere (TOGA) array, while section 8

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