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To improve the ensemble prediction system of the tropical regional atmosphere model for the South China Sea (TREPS) in predicting landfalling tropical cyclones (TCs), the impacts of three new implementing strategies for surface and model physics perturbations in TREPS were evaluated for 19 TCs making landfall in China during 2014–16. For sea surface temperature (SST) perturbations, spatially uncorrelated random perturbations were replaced with spatially correlated ones. The multiplier f, which is used to form perturbed tendency in the Stochastically Perturbed Parameterization Tendency (SPPT) scheme, was inflated in regions with evident convective activity (f-inflated SPPT). Lastly, the Stochastically Perturbed Parameterization (SPP) scheme with 14 perturbed parameters selected from the planetary boundary layer, surface layer, microphysics, and cumulus convection parameterizations was added. Overall, all these methods improved forecasts more significantly for non-intensifying than intensifying TCs. Compared with f-inflated SPPT, the spatially correlated SST perturbations generally showed comparable performance but were more (less) skillful for intensifying (non-intensifying) TCs. The advantages of the spatially correlated SST perturbations and f-inflated SPPT were mainly present in the deterministic guidance for both TC track and wind and in the probabilistic guidance for reliability of wind. For intensifying TCs, adding SPP led to mixed impacts with significant improvements in probability-matched mean of modest winds and in probabilistic forecasts of rainfall; while for non-intensifying TCs, adding SPP frequently led to positive impacts on the deterministic guidance for track, intensity, strong winds, and moderate rainfall and on the probabilistic guidance for wind and discrimination of rainfall. [ABSTRACT FROM AUTHOR]

A comprehensive observational study on a warm sector torrential rain(WSTR) on 20 May 2016 over south China is presented with a pioneering examination of simulation capabilities based on the Global/Regional Assimilation and Prediction System for Tropical Mesoscale Model(GRAPES_TMM). The results show that the meso-scale convective boundary formed between north wind from mountainous areas and the south wind from plain regions as well as the cold outflows boundary both contribute to the convections over Xinyi, and the convections were blocked and stayed stagnant in the trumpet-shaped topography for about 8 hours which eventually caused the torrential rains.Comparative verifications of the observational studies by simulations showed that GRAPES_TMM had better estimations of large-scale frontal precipitation than the local warm-sector torrential rains. The simulations of local torrential rains in the warm sector showed strong biases in precipitation location and amount. GRAPES_TMM also showed overestimated surface winds and a faster moving speed bias, as well as an overall underestimation of the nocturnal surface temperature during the WSTR. This work may lead to several prospective researches of its model improvements on model physics such as land surface process and PBL parameterization. [ABSTRACT FROM AUTHOR]

Purpose – Research on workplace loneliness has thus far been dominated by perceptions of followers; hence, few researchers have considered the perspective of leader-follower congruence. The purpose of this paper is to examine how the leader-follower relationship mediates the relationship between leader-follower congruence/incongruence in workplace loneliness and turnover intentions. Design/methodology/approach – Data were collected from 232 leader-follower dyads from ten companies in China. Polynomial regression combined with the response surface methodology was used to test the hypotheses. Findings – Four conclusions were drawn. First, leader-member exchange (LMX) was higher when leaders and followers were aligned in terms of workplace loneliness than otherwise. Second, in the case of leader-follower congruence, LMX rose as their workplace loneliness fell. Third, in the case of incongruence, followers had lower LMX when they were lonelier than their leaders. Finally, LMX partially mediated the leader-follower congruence/incongruence effect of workplace loneliness on followers’ turnover intention. Originality/value – This study emphasized the importance of leaders’ congruence with followers in workplace loneliness. Additionally, it extended research on leader-follower congruence from a positive perspective to a negative one. [ABSTRACT FROM AUTHOR]