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Masakazu Taguchi

1. Introduction The meridional circulation in the tropical troposphere is characterized by the thermally driven Hadley circulation, whereas that in the stratosphere is known as the wave-driven Brewer–Dobson (BD) circulation (e.g., James 2003 ; Holton et al. 1995 ). In the stratosphere, the wave driving of the BD circulation is primarily induced by planetary waves (PWs). Because the zonally asymmetric surface conditions in the Northern Hemisphere (NH) are the dominant driver of PWs, the PW

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Joseph A. Santanello Jr., Joshua Roundy, and Paul A. Dirmeyer

1. Introduction Land–atmosphere (L–A) interactions and coupling remain weak links in current approaches to understanding and improving predictions of the Earth–atmosphere system and its variability in a changing climate. However, recent community-based efforts (e.g., LandFlux; Mueller et al. 2013 ) have shown that current observational and model products have significant uncertainty and spread in surface [e.g., evapotranspiration (ET)] and planetary boundary layer (PBL) water and energy budget

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Chengyun Yang, Tao Li, Anne K. Smith, and Xiankang Dou

.g., Matthews and Meredith 2004 ; Lin et al. 2009 ; Seo and Son 2012 ; Cassou 2008 ) and in turn excite planetary waves (PWs) in the middle and high latitudes ( Ferranti et al. 1990 ; Seo and Son 2012 ). As suggested by previous studies, the MJO teleconnection is characterized by a Rossby wave train propagating from the heating source to higher latitudes (e.g., Matthews and Meredith 2004 ), which in turn results in anomalies over Asia, the North Pacific, North America, and the Atlantic (e.g., Higgins

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Zhaomin Wang and Lawrence A. Mysak

Table 2 . Here we only discuss the new parameters and those parameters that are significantly different from those in Bjornsson et al. (1997) . In this study, the atmospheric albedo α A is introduced, whereas the planetary albedo α P = 0.315 + 0.3615 s 2 ( s = sin ϕ ) is used in Bjornsson et al. For a one-layer atmosphere model, there is a relationship between α A and α P , that is, α P = α A + (1 − α A ) a 2 α S , (46) where α S is surface albedo. In Bjornsson et al., the underlying

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Chia-Chi Wang, Wei-Liang Lee, Yu-Luen Chen, and Huang-Hsiung Hsu

of low clouds ( Klein and Hartmann 1993 ). A warmer SST and a less stable lower atmosphere lead to unrealistic convection. The double ITCZ structure is then enhanced by these positive feedbacks in GCMs. However, the causes of the overly strong trade winds and insufficient cloudiness are not discussed in previous studies. Recently, some studies suggested that the source of the double ITCZ bias is in the atmospheric component, particularly the deep convection scheme ( Song and Zhang 2009 ; Hirota

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Adam Hugh Monahan

an empirical model without a mechanistic basis. Also plotted in Fig. 1 is the relationship between moments simulated by an idealized model of the boundary layer momentum budget ( Monahan 2004 , 2006a ). In this model, the horizontal momentum tendency includes contributions from surface turbulent momentum fluxes (quadratic in the surface wind speed), the turbulent exchange of momentum between the boundary layer and the free atmosphere, and “ageostrophic tendencies” with specified mean and

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Yunfeng Cao, Shunlin Liang, Xiaona Chen, and Tao He

methods to generate the radiative kernels: 1) a physically based regression model that expresses planetary albedo as a function of different contributions, such as surface albedo, cloud cover, and cloud optical thickness ( Qu and Hall 2006 ); 2) an analytical model that expresses planetary albedo as the sum of the contributions of surface and atmosphere, each with an analytical function ( Donohoe and Battisti 2011 ); and 3) a simulated method using an offline radiative transfer code to calculate the

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Peter A. Bogenschutz, Andrew Gettelman, Hugh Morrison, Vincent E. Larson, Cheryl Craig, and David P. Schanen

, 17 , 2494 – 2525 . Bogenschutz , P. A. , A. Gettelman , H. Morrison , V. E. Larson , D. P. Schanen , N. R. Meyer , and C. Craig , 2012 : Unified parameterization of the planetary boundary layer and shallow convection with a higher-order turbulence closure in the Community Atmosphere Model . Geosci. Model Dev. , 5 , 1407 – 1423 . Bonan , G. B. , P. J. Lawrence , K. W. Oleson , S. Levis , M. Jung , M. Reichstein , D. M. Lawrence , and S. C. Swenson

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Takafumi Miyasaka and Hisashi Nakamura

.e., the Canary or California Current). The strong surface northerlies along the eastern flank of the high act to maintain cool sea surface temperatures (SSTs) underneath by enhancing surface evaporation and coastal upwelling. The presence of the cool SSTs and a midtropospheric subsidence favors the local development of marine stratus in the planetary boundary layer (PBL) ( Klein and Hartmann 1993 ). Their high albedo also acts to maintain the cool SSTs ( Hartmann et al. 1992 ). One of the important

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John A. Dutton

greenhouse gases is developed from a time-dependent version of the global energy budge~. Themodel clarifies the role of feedback and system heat capacity in controlling the magnitude and rate of response. Observed seasonal changes in surface temperature, radiative fluxes, and planetary albedo are combined toestimate the atmospheric feedback and the net gain of the system. A simple model of ocean upwelling anddiffusion then yields an estimate of the heat capacity and thus the time constant of the

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