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Kirsty E. Hanley and Stephen E. Belcher

examined the role of ocean surface waves in shaping the wind profile in the marine atmospheric boundary layer. The focus has been the wave-driven wind regime, which observations suggest occurs when fast-moving swell propagates into regions of low geostrophic winds. The wave-induced stress decays over a shallow depth of the order 5 m, and so it might be thought that the waves have little influence in controlling the dynamics of the boundary layer. Using the classical Ekman model augmented with a term

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Youichi Tanimoto, Shang-Ping Xie, Kohei Kai, Hideki Okajima, Hiroki Tokinaga, Toshiyuki Murayama, Masami Nonaka, and Hisashi Nakamura

surface wind curls ( Schneider and Miller 2001 ; Qiu 2003 ). Strong ocean advection and the deep winter mixed layer allow subsurface variability to affect SST ( Xie et al. 2000 ; Tomita et al. 2002 ) and surface heat flux ( Tanimoto et al. 2003 ). Strong SST gradients east of Japan maintain baroclinicity in the marine atmospheric boundary layers (MABL), which has been suggested as being important for atmospheric storm tracks ( Inatsu et al. 2003 ; Nakamura et al. 2004 ). While most studies of the

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Peter P. Sullivan, James C. McWilliams, Jeffrey C. Weil, Edward G. Patton, and Harindra J. S. Fernando

layer currents. Air–sea coupling, accounting for a wavy interface ( Sullivan and McWilliams 2010 ) and ocean heterogeneity, is a broadband space–time process fundamentally rooted in the turbulent marine atmospheric boundary layer (MABL) and oceanic boundary layer (OBL) and remains an important research area for improving weather forecasts and climate predictions ( Small et al. 2008 ). Ocean submesoscale heterogeneity is subgrid in global models, and by necessity these models rely on single column

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Tao Luo, Renmin Yuan, Zhien Wang, and Damao Zhang

1. Introduction Sea salt is one of the largest natural contributors to the global aerosol loading and thus plays a significant role in the global climate ( Solomon et al. 2007 ). Sea salt dominates submicron and supermicron scatterers and total aerosol mass concentration in the marine boundary layer (MBL) ( Sievering et al. 2004 ). However, its radiative forcing is still poorly simulated in models ( Textor et al. 2006 ; Kinne et al. 2006 ). One important uncertainty is from the lack of a

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Guang J. Zhang, Andrew M. Vogelmann, Michael P. Jensen, William D. Collins, and Edward P. Luke

1. Introduction Marine boundary layer (MBL) clouds have a strong shortwave cloud radiative forcing on the earth’s climate system ( Klein and Hartmann 1993 ). They form in the cold water regions off the west coast of major continents; via strong radiative cooling, they play an important role in modulating the sea surface temperatures (SSTs). However, their simulation in global climate models (GCMs) is among the most problematic, and few models can simulate the extent of these clouds ( Ma et al

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Timothy A. Myers and Joel R. Norris

1. Introduction Low-level clouds have the largest net cloud radiative effect of all cloud types, acting to cool the planet via high albedo and a weak greenhouse effect ( Hartmann et al. 1992 ). The large and persistent decks of stratus and stratocumulus over eastern subtropical oceans are the primary contributors to this cooling effect. These clouds occur predominantly within a shallow, well-mixed marine boundary layer (MBL) over cool sea surface temperatures (SSTs) and under a strong

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Richard J. Foreman and Stefan Emeis

1. Introduction Despite conflicting evidence in the past ( Garratt 1977 ), it is now accepted that the drag coefficient (defined below) in the marine atmospheric boundary layer (MABL) is an increasing function of the wind speed ( Sullivan and McWilliams 2010 ) for moderate wind speeds. At higher wind speeds, however, recent evidence suggests that the drag coefficient tends toward a constant value ( Donelan et al. 2004 ; Black et al. 2007 ). The exact equation that describes the relationship

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Katherine M. LaCasse, Michael E. Splitt, Steven M. Lazarus, and William M. Lapenta

processes involved in the response of the marine atmospheric boundary layer (MABL) to tropical instability waves using a regional climate model. For that case, vertical mixing was important to latent and sensible heat fluxes and horizontal mixing had a small effect by advecting the SST impact downstream. The horizontal perturbation pressure gradient was shown to be significant, because it drove the near-surface wind speed changes across the SST gradients. In a study by Song et al. (2004) , the fifth

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Peter P. Sullivan, James C. McWilliams, and Edward G. Patton

-wave coupling processes in the marine atmospheric boundary layer (MABL); for example, the vertical extent of the wave-impacted (or wave induced) layer above the ocean surface, the role of swell, the validity of Monin–Obukhov (MO) similarity theory to predict surface fluxes, the correlation between winds and waves for varying wave state, and how wave-influenced surface wind and pressure fields blend into the bulk of the MABL, to mention just a few. Also there is still vigorous debate as to the mechanisms

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Michael P. Jensen, Andrew M. Vogelmann, William D. Collins, Guang J. Zhang, and Edward P. Luke

1. Introduction Marine boundary layer (MBL) clouds represent a climatologically significant influence on the global energy and water cycle ( Randall et al. 1984 ). Because they possess an albedo that is much larger than the underlying ocean surface, these clouds cause a significant decrease in the amount of solar radiation absorbed in the ocean’s mixed layer, with minimal compensation in thermal radiation emitted to space. In fact, observations of the top-of-atmosphere radiation balance

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