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Chen Li, Jing-Jia Luo, and Shuanglin Li

-scale precipitating events are handled by the convection scheme. The model uses a mass flux convection scheme based on Gregory and Rowntree (1990) with various extensions to include downdrafts ( Gregory and Allen 1991 ) and convective momentum transport. To depict the large-scale cloud, UM-GA6’s prognostic cloud fraction and prognostic condensate (PC2) scheme ( Wilson et al. 2008a , b ) along with the modifications to the cloud erosion parameterization described by Morcrette (2012) are used. The “boundary

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James H. Ruppert Jr., Xingchao Chen, and Fuqing Zhang

in order to test the study objectives, which are as follows: To assess the dynamic origins of diurnal gravity waves in the MC region and the specific role of orography for these waves. To quantify the nonlinear response to the synchronized diurnal forcing of Borneo and Sumatra. 2. Methodology The regional cloud-permitting numerical model framework of this study is based on that of Wang et al. (2015) , who invoked the Weather Research and Forecasting (WRF) Model, version 3.4.1 ( Skamarock et al

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D. Argüeso, R. Romero, and V. Homar

resolution of circa 0.3° by 0.3°. These high-resolution forcing data allowed us to design a novel approach to quantify the role of the model spatial resolution by running WRF at multiple resolutions over a single domain in separate experiments (no nesting), all directly driven by ERA5 at their boundaries. This results in a comparable set of simulations at resolutions of 32, 16, 8, 4, and 2 km that run independently from each other and are identical in all other configuration parameters. The approach

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Chu-Chun Chen, Min-Hui Lo, Eun-Soon Im, Jin-Yi Yu, Yu-Chiao Liang, Wei-Ting Chen, Iping Tang, Chia-Wei Lan, Ren-Jie Wu, and Rong-You Chien

decreased low clouds also correspond to more incoming downward solar radiation but also less downward longwave radiation at the surface. The increased mid- and high-level clouds are associated with less incoming downward solar radiation but more downward longwave radiation. Therefore, the changes in net cloud forcing at the land surface are minimal. Regarding the surface radiation budget, the increase in surface albedo (1.38%, with p value < 0.05) from the deforestation and the increase in total cloud

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Giuseppe Torri, David K. Adams, Huiqun Wang, and Zhiming Kuang

Trenberth 2004 ). This problem can have a number of repercussions, including on the calculation of Earth’s radiation budget, given the importance of the relative phase between solar radiation and cloud cover. One reason for this early bias in precipitation could be that the onset of deep convection, or the transition from shallow to deep convection, in the models has inadequate dependence on midtropospheric humidity. From a conceptual point of view, the dynamical features that participate in the

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Chidong Zhang and Jian Ling

by topographic interference would impair the MJO ( Hsu and Lee 2005 ; Inness and Slingo 2006 ; Wu and Hsu 2009 ). It has been suggested that cloud–radiation interaction is the source of instability for the MJO and sets its intraseasonal rhythm ( Hu and Randall 1994 , 1995 ; Sobel and Maloney 2013 ; Adames and Kim 2016 ). This interaction can be interrupted by persistent diurnal convection over islands ( Neale and Slingo 2003 ; Hagos et al. 2016 ) that is almost synchronized throughout the

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Ming Feng, Yongliang Duan, Susan Wijffels, Je-Yuan Hsu, Chao Li, Huiwu Wang, Yang Yang, Hong Shen, Jianjun Liu, Chunlin Ning, and Weidong Yu

The Madden–Julian oscillation (MJO) is an eastward-moving disturbance of clouds, rainfall, winds, and pressure that traverses the globe in the tropics with a period in the range of 30–80 days. The MJO is the dominant mode of intraseasonal variability in the tropical Indo-Pacific warm pool ( Zhang 2005 ). It modulates the timing and strength of monsoons and is an important influence for the development of some high-impact weather events such as tropical cyclones, flood, and drought in the Indo

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James H. Ruppert Jr. and Fuqing Zhang

; namely, their role in forcing and coupling with long-lived gravity waves. Among the most dominant drivers of weather variability in the MC is the Madden–Julian oscillation (MJO; Madden and Julian 1972 ). The MJO is a convectively coupled tropical wave that propagates slowly eastward (~5 m s −1 ) through the Indo-Pacific warm pool region, modulating deep overturning motion and moist convection on intraseasonal time scales ( Zhang 2005 ). Yet since the diurnal cycle is the primary rainfall mechanism

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Jieshun Zhu, Wanqiu Wang, and Arun Kumar

region strengthen or weaken the surface winds, which reduce or enhance the latent heat flux (LHF) at the ocean surface. Further, variations in solar shortwave radiation flux (SWF) at the surface associated with MJO-related changes in cloudiness also occur. The combination of these flux variations can induce SST anomalies to the east and west of the convective region. The zonal SST gradient causes zonal changes in surface moist static energy and provides surface forcing, which induces the convection

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Kevin E. Trenberth and Yongxin Zhang

Zealand downstream. Hence the change in local winds also force some modifications in surface fluxes and wind stress. Any link between ENSO-related variations in the ITF and the Tasman Sea heat waves has been generally assigned to the atmospheric bridge connections. The studies thus far have overlooked the likelihood that there is also a direct ocean connection through the changes in mass and heat transport with the ITF that indeed relate to opposite changes in the East Australian Current region

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