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There are many ships and ports in Shanghai coastal zones, where disastrous weather occurs frequently. Meteorological disasters often threaten the safety of people’s lives and properties along the coast and in the ports. In the past, the meteorological warnings for Shanghai coastal zones are mainly based on those issued for Yangshan Port by Shanghai Marine Meteorological Centre (SMMC), which are called “unified warnings”. However, there are obvious differences in the time and intensity of meteorological disasters in each region, and the unified warnings cannot meet the needs of the production and operation of the shipping and ports. In 2020, Shanghai coastal zones were divided into five sub-zones, where the meteorological forecast and warnings were carried out separately from July 2020. Based on hourly observational data of the representative stations in Shanghai coastal zones and warning signal data from 2016 to 2022, the gale events are selected to analyse the statistical characteristics of temporal and spatial distribution and evaluate the forecast quality and the economic benefits of the zonal warnings. The results show that: (1) The farther away from the coastline, the more gale days, the higher the wind speed and the longer the duration; the higher the wind speed during the process, the more obvious the difference of wind scale. In particular, the wind scale caused by typhoons can range up to 5 levels. (2) Compared with the “unified warning”, the missing alarm rate (MAR) of gale warnings in each sea area has been reduced significantly, by up to 5%, the false alarm rate (FAR) for the western part of Yangtze River estuary is reduced by more than 8% and the TS score is significantly improved by more than 10%. (3) The advance time of gale warnings has been reduced by more than 3 hours, the maintaining duration has been shortened by more than 16 hours at most, which can reduce the loss of nearly 18 million RMB and improve the production efficiency of the coastal zones of Shanghai greatly. The results of this paper show that refined marine meteorological forecasts and early warnings provide a safety guarantee for marine transportation and port production operations, resulting in significant social and economic benefits and the enhancement of the comprehensive guarantee level of marine meteorological services in Shanghai. In the next step, we will continue to research and develop more refined objective forecast methods adapted to this business, then build a regional shared operational system platform and extend it to the Yangtze River Delta region, so as to promote the high-quality development of shipping meteorological integration in the Yangtze River Delta region.

The characteristics of 21 tropical cyclones (TCs) and associated high winds in Shanghai from 2005 to 2020 are analyzed based on the TC best track data, surface observations, and ERA5 reanalysis dataset. Results indicate that 95% of the TCs causing high winds in Shanghai were generated during July to September, and located to the south of Shanghai for ~80% of the impact time. Divided into four categories according to tracks, the TCs show significant discrepancies in genesis month and location, intensity, size, and duration. The findings of high winds in Shanghai highlight the combination effect of TC intensity, track, and the distance between TCs and Shanghai normalized by TC size (NDSH-TC). The maximum 10‐min sustained (Vmax) and extreme 3‐s wind speeds (Vex) in Shanghai only increase slightly with TC intensity, due to the fact that the stronger TCs are usually farther away from Shanghai. The Vmax and Vex differ in response to different TC tracks and reach the maximum value under TCs moving northward across the land west of Shanghai and the sea east of Shanghai, respectively. The urban and coastal wind speeds are the smallest and the largest respectively, indicating that the largest underlying surface roughness is associated with the most rapid urban construction. The wind speeds under the influence of TCs in four quadrants of Shanghai also present different variations with the NDSH-TC. Additionally, the wind direction in Shanghai is regularly related to the relative position between the TC center and Shanghai. A case study combined with TC In‐Fa (2106) verified the validity of the conclusions, which can provide a reference for TC forecasters to make more accurate wind field predictions. [ABSTRACT FROM AUTHOR]

Typhoon Lekima (2019), the 9th typhoon in 2019, caused severe rainstorm during its impact on Shanghai from August 9 to 11, 2019. Based on the ERA-5 hourly reanalysis datasets and the ground observational data with high spatial and temporal resolution in Shanghai, the present study analyzed the causes of the severe precipitation by using the ageostrophic Q-vector decomposition method. The results showed that the severe precipitation associated with Lekima (2019) in Shanghai dominantly came from the spiral rainbands on the east side of the typhoon. The relative humidity at each boundary of the severe precipitation area varied significantly with time in the vertical direction. The vertical transport of water vapor and the water vapor flux in the whole atmosphere played an important role in this severe precipitation event. Furthermore, ageostrophic Q-vector decomposition was used to reveal that the large-scale system on the eastern boundary and the mesoscale system on the northern boundary played a major role. The maximum forcing center descended from the upper to the lower atmosphere after the whole atmosphere was uplifted when the typhoon made landfall, and the mesoscale forcing effect was more obvious than that of the large-scale forcing, which was conducive to the occurrence of severe precipitation. [ABSTRACT FROM AUTHOR]

Uniconazole (UNZ) can alleviate a variety of abiotic stresses such as low temperature. With application of UNZ on Coix lachryma‐jobi L. (coix) under low‐temperature stress, growth and physiological parameters were investigated in seedlings. Meanwhile, transcriptome profile in coix seedlings was characterized as well. The results showed an increase of 11.90%, 13.59%, and 10.98% in stem diameter, the aboveground and belowground biomass in 5 mg/L uniconazole application group (U3), compared with control check low‐temperature group (CKL). Some anti‐oxidase activities also show significant difference between CKL and U3 (p <.05). Transcriptome results showed that 3,901 and 1,040 genes had different expression level at control check (CK) and CKL, CKL and U3. A considerable number of different expressing genes (DEGs) related to the plant hormone signal transduction, photosynthesis, reactive oxygen species (ROS)‐related genes, and secondary metabolism in response to uniconazole application were identified in this study. The transcriptomic gene expression profiles present a valuable genomic tool to improve studying the molecular mechanisms underlying low‐temperature tolerance in coix. At the same time, it would provide a certain basis for the application of UNZ in the production of coix resistance under low temperature. [ABSTRACT FROM AUTHOR]