Influence Of Typhoon Research Articles

Responses of Yellow Sea Cold Water Mass to Typhoon Bolaven

A two-month seabed-mounted observation (YSG1 area) was carried out in the western Yellow Sea Cold Water Mass (YSCWM) using an RDI-300K acoustic Doppler current profiler (ADCP) placed at a water depth of 38 m in late summer, 2012. On August 2012, Typhoon Bolaven passed east of YSG1 with a maximum wind speed of 20 m s−1. The water depth, bottom temperature, and profile current velocities (including u, v and w components) were measured, and the results showed that the typhoon could induce horizontal current with speed greater than 70 cm s−1 in the water column, which is especially rare at below 20 meters above bottom (mab). The deepening velocity shear layer had an intense shear velocity of around 10 cm s−1 m−1, which indicated the deepening of the upper mixed layer. In the upper water column (above 20 mab), westward de-tide current with velocity greater than 30 cm s−1 was generated with the typhoon’s onshore surge, and the direction of current movement shifted to become southward. In the lower water column, a possible pattern of eastward compensation current and delayed typhoon-driven current was demonstrated. During the typhoon, bottom temperature variation was changed into diurnal pattern because of the combined influence of typhoon and tidal current. The passage of Bolaven greatly intensified local sediment resuspension in the bottom layer. In addition, low-density particles constituted the suspended particulate matter (SPM) around 10 mab, which may be transported from the central South Yellow Sea by the typhoon. Overall, the intensive external force of the Typhoon Bolaven did not completely destroy the local thermocline, and most re-suspended sediments during the typhoon were restricted within the YSCWM.

Effects of typhoon Roke and Haitang on phytoplankton community structure in northeastern South China sea

ABSTRACT The influence of typhoon and Kuroshio intrusion process on the natural phytoplankton assemblages in the northeastern South China Sea (neSCS) was examined during a cruise in summer 2017. One hundred ninety-six seawater samples were collected and analyzed in the neSCS. In total, 299 species were identified belonging to 82 genera, mostly dominated by Bacillariophyta (159), followed by Dinophyta (132), Cyanophyta (4) and Chrysophyta (4). Among all, Thalassionema nitzschioides, Thalassionema frauenfeldii, Thalassiosira minima, in Bacillariophyta, Prorocentrum lenticulatum, Prorocentrum compressum in Dinophyta, and Trichodesmium thiebautii, in the Cyanophyta were the most dominated species, respectively. Correlation analysis shows compared with other groups Bacillariophyta was mostly influenced by silicate, whereas, Dinophyta and Cyanophyta showed significant correlation with temperature, salinity, phosphate, and nitrate. After the typhoon, the higher abundance of Dinophyta was observed, whereas it was lower in case of Bacillariophyta and Cyanophyta, shows typhoon “Roke“ and ”Haitang” had a significant influence on the phytoplankton assemblages, which could be manifested by the variations of total phytoplankton abundance in the surface water of neSCS. Overall, our present study provides the latest in-depth information about how the environmental factors influencing the phytoplankton density and diversity in the neSCS during summer.

台风灾害下海岸带城市社会-生态系统脆弱性评估——大数据视角

PDF HTML阅读 XML下载 导出引用 引用提醒 台风灾害下海岸带城市社会-生态系统脆弱性评估——大数据视角 DOI: 10.5846/stxb201808101709 作者: 作者单位: 厦门大学环境与生态学院,厦门大学环境与生态学院,厦门大学环境与生态学院,厦门大学环境与生态学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划（2016YFC0502904）；厦门大学大学生创新创业训练计划项目（103842017103） Vulnerability assessment of urban socio-ecological systems in coastal zones under the influence of typhoons:Big data perspective Author: Affiliation: Xiamen University,,, Fund Project: The National Key Research and Development Program (2016YFC0502904);The innovation and entrepreneurship training program for undergraduates of Xiamen University (103842017103) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:2016年莫兰蒂台风对厦门城市社会-生态系统造成重创，该系统在灾害影响下的脆弱性成为亟待研究的重要问题。基于新浪微博平台进行大数据挖掘，结合统计年鉴及空间基础数据，建立台风灾害影响下基于暴露-敏感-应对-恢复力体系的海岸带城市社会-生态系统脆弱性指标体系，评估灾前灾后台风对厦门不同地区的影响；同时根据微博大数据的定位信息，对不同受灾信息进行灾情跟踪及分析，结果表明，在本次台风灾害中思明、湖里区表现出的脆弱性较低，而海沧、集美区表现出的脆弱性较高，主要是由于思明、湖里区的应对能力明显高于其他各区，从大数据显示的恢复情况来看，除海沧区外，其他三区在电力方面的恢复速度都较为迅速。研究成果能够为台风灾害背景下的城市脆弱性评价提供新的方法与技术，为灾前防治、灾后恢复提供决策参考。 Abstract:With the increase in the intensity and frequency of natural disasters, the risk and loss assessment of urban natural disasters and the construction of an urban security pattern are becoming more important. Based on social media data from the Sina microblogging platform, statistical yearbook data, and using the ArcGIS software, this study establishes a typhoon disaster vulnerability index for the rapid assessment of the impact of Typhoon "Meranti" on different districts of Xiamen at different stages. The location of a specific microblog information from the microblogging platform is used to track and analyze disaster information. The results show that when facing a typhoon disaster, the Siming and Huli District showed relatively low vulnerability, while Haicang and Jimei District showed higher vulnerability, which is mainly due to the quick response of local government and civil society organization in Siming and Huli District. From a perspective of recovery, except for the Haicang District, the speed of recovery of power in the other districts is relatively rapid. This study provides a new method and technology for the evaluation of typhoon disaster vulnerability, decision reference for pre-disaster control, and post-disaster recovery. 参考文献 相似文献 引证文献

Diatoms in the Amur Bay sediments (Sea of Japan) and the impact of typhoons on their accumulation over the last 2000 years

The study of diatoms in the sediments of the Amur Bay (Sea of Japan), formed over the last 2000 years, showed that the sharp short-term drops in the concentration of diatoms coincide with the minima of bromine content, which can be explained by the influence of typhoons or other catastrophic events leading to floods and used later in paleoreconstructions.

The response of cyclonic eddies to typhoons based on satellite remote sensing data for 2001–2014 from the South China Sea

Eddies are known to be affected by typhoons, and in recent years, the general three-dimensional structure, as well as features of the spatial and temporal distributions of eddies have been determined. However, the type of eddy that is most likely to be affected by a typhoon remains unclear. In this paper, quantitative and qualitative methods were used to study the eddies that are most sensitive to upper-ocean tropical cyclones (TCs) from the perspective of eddy characteristics, and the quantitative results showed that not all eddies were enhanced under the influence of typhoons. Enhancement of the eddy amplitude (Amp), radius (Rad), area (A), or eddy kinetic energy (EKE) accounted for 92.3% of the total eddy within the radius of the typhoon. Qualitative analyses showed the following: First, eddies located on different sides of the typhoon tracks were differently affected, as eddies on the left side were more intensely affected by the typhoon than eddies on the right side, and second, eddies with short lifespans or small radii were more susceptible to the TCs.

Dynamical Response of Changjiang River Plume to a Severe Typhoon With the Surface Wave‐Induced Mixing

AbstractTyphoons (or hurricanes) are the most energetic atmospheric forcing acting on coastal waters. Here in this study, we investigated the response of the summertime Changjiang River plume to a typical typhoon, Chan‐hom (1509), with a combination of field observation and numerical simulation. Surface wave‐induced mixing was considered in the model configuration. The results showed that the typical offshore‐extending summer Changjiang River plume completely disappeared under the influence of typhoon wind. Instead, it extended southward along the Zhejiang and Fujian (Zhe‐Min) coast as a typical wintertime Changjiang River plume. The along‐shelf plume extension lasted for extra ~10 days after the typhoon passage, until another strong weather event came. The competition between wind‐driven current and buoyancy‐driven current dominated the recovery of the Changjiang River plume. Through calculation, we found that the freshwater transported to the Zhe‐Min Coastal Water reached ~4.7 × 1010 m3 as influenced by typhoon Chan‐hom, which was ~5% of the total Changjiang River discharge in 2015 or ~12% of the total dry season Changjiang River discharge (October‐April) when the majority of Changjiang River plume extended to Zhe‐Min Coastal Water. The remote sensing data of chlorophyll‐α from Geostationary Ocean Color Imager also showed that significant algal bloom occurred when the southward extending Changjiang River plume retreated. Surface wave‐induced mixing caused by typhoon wind was found to be important in destroying the vertical plume stratification and elongating the recovery processes from the typhoon influence.

The Influence of Typhoon on the Guangdong Power Grid and Countermeasures

The Influence of Typhoon on the Guangdong Power Grid and Countermeasures

Modeling beach profile changes by typhoon impacts at Xiamen coast

For the Xiamen coast where typhoon frequently occurs, beaches are subject to severe erosion during typhoons. To investigate storm-induced beach profile changes at Xiamen coast, four inner XBeach models were applied using typhoon Dan as a case study. These numerical simulations utilized hydrodynamic and wave conditions determined from larger-scale outer and middle coupled Delft3D-FLOW and SWAN models. The models were validated against historic measurements of tidal level, storm tide, storm surge and beach profiles, thus showing the accuracy of outer and middle models to provide boundary conditions and the reliability of inner models to reflect beach profile changes during a typhoon process. The applicability of this modeling approach to Xiamen coast was verified. The results also demonstrated that an enormous amount of dune face erosion occurred at the selected beaches during the typhoon Dan process and the slopes in the vicinity of zero elevation for the chosen four beach profiles all turned out to be gentler after typhoon Dan. Nevertheless, these beaches suffered different impact degrees and processes during the typhoon influence period. Compared to swash and collision regimes, overwash and inundation regimes have the ability to alter beach profile rapidly in short time. Post-storm beach profile with and without vegetation indicated that vegetation is capable of protecting coastal beaches to some extent. By running the nested models, the simulated results can be employed in the management of the beach system and the design of beach nourishment projects at Xiamen coast.

Impact of Typhoon Chan-hom on the marine environment and sediment dynamics on the inner shelf of the East China Sea: In-situ seafloor observations

The suspended sediment transport in the inner shelf of the East China Sea (ECS) varies seasonally, and most of the suspended sediments are transported southward in winter. However, the influence of typhoons, which usually take place in summer, on the marine environments and sediment transport processes in the mud wedge area of the ECS inner shelf has not been elucidated. An in-situ monitoring platform moored approximately 440 km south of the Yangtze River mouth at a water depth of 40 m was resting on the seabed of the ECS inner shelf when Typhoon Chan-hom passed through the area. A 49-day data set of the temperature, suspended sediment concentration (SSC), chlorophyll a (chl a) concentration, and currents was recorded from this platform and analyzed in this study to characterize Typhoon Chan-hom and evaluate the associated sediment transport. The analysis of the data obtained shows that during the typhoon passage, the temperature decreased by approximately 0.8 °C, the maximum near-bottom current reached 152.0 cm/s, an average SSC of 919 mg/L was observed with peak hourly values exceeding 1785 mg/L, and the SSC and chl a concentrations reached approximately 50 and 10 times the corresponding values during the pre-typhoon period, respectively. During the typhoon passage, most of the suspended particles near the seabed were derived from the resuspension of bottom surface sediments. The chl a concentration near the seabed increased greatly because of surface sediment resuspension and the input of additional terrigenous nutrients transported by the typhoon passage. The net suspended sediment flux (SSF) associated with the passage of Typhoon Chan-hom was directed southwestward and landward. Sediment transport during Chan-hom accounted for approximately 89% of the total southwestward SSF and 44% of the total landward SSF during the whole observation period. Analysis of the wavelet power spectra reveals that in the upper water layers, the semidiurnal tidal currents prevailed before and after the typhoon passage; however, this dominant factor disappeared during the typhoon passage. Compared with winter storms in the ECS, summer typhoons such as Chan-hom mainly transport locally resuspended sediments, and sediment flux is landward in the across-shelf direction. Our study highlights the significant role of typhoons in the resuspension and redistribution of sediments and transport of suspended matter from north to south in the mud wedge area of the ECS.

Analysis of Wind Field Characteristics of Satallite Remote Sensing Image Based on EOF Change

By using empirical orthogonal function (EOF) and statistical analysis methods expansion, the paper analyzed the daily and monthly data of the ASCAT satellite in the Taiwan Strait in 2016 to explore the seasonal variation characteristics and spatial pattern of the sea wind field in the Taiwan Strait. The results showed the sea surface wind field of 2016 in the Taiwan Strait had obvious seasonal change with a trend of decreasing after increasing firstly throughout the year of 2016, the wind speed decreased from January to June, and increased from June to December through the whole year. The EOF expansion of wind speed showed that the maximum center of outliers deviation existed in the narrow straits of Taiwan Strait and distributed along the coastline from the first modal space pattern, revealed the influences of Taiwan island topography were obvious. Furthermore, the winter-summer monsoon oscillation was reflected from the time curve of the year of 2016, and the typhoon influence signal could be well corresponded in details, shown as strong amplitude in the time curve. The spatial pattern of second modal presented in zonal distribution, characterized by reverse structure from south to north. The EOF expansion of wind direction showed the spatial pattern distributions of the first and second modals were zonal, and the maximum center of outliers deviation existed in the north and south sides of Taiwan island affected by the island terrain, in particular, the typhoon influences on the direction of the wind were obvious from the time curves.

Effect of typhoon with extreme precipitation on mountain reservoir drinking water treatment: a case study in Ningbo, China

ABSTRACTDue to frequent drinking water pollution accidents in the past decade, it is common that mountain reservoirs were used as the source of drinking water in China. However, some coastal areas frequently suffer from typhoon with extreme precipitation, which results in the water quality deterioration of the reservoirs. The influence of typhoons with extreme precipitation on Jiaokou reservoir and the emergency treatment process of Maojiaping water treatment plant in the past three typical typhoons with extreme precipitation from the year of 2012–2015 were studied. It was found that the degradation of water quality, such as the increase of turbidity and bacteria index, may not merely appear during the events, but last for several days. Changing the dosage of water purification agent, such as coagulant and disinfectant at right time and place may be an efficient emergency water treatment process. Based on the analysis of water quality variation rule during and after the events, it was also found that emer...

Diatom bloom‐derived bottom water hypoxia off the Changjiang estuary, with and without typhoon influence

AbstractDuring the summers of 2009 and 2013, seawater pH and concentrations of dissolved oxygen, inorganic carbon, and nutrients were measured off the Changjiang estuary in the East China Sea. The 2009 cruise captured the effects of Typhoon Morakot; the 2013 cruise sampled more typical conditions (no typhoon). Data from both years indicate a close correlation between high primary productivity in surface waters and hypoxia in bottom waters. Based on these observations, we developed a conceptual model to guide an exploration of processes contributing to the formation of summertime bottom hypoxia. A mixing‐model analysis of the 2009 data identified a surface diatom bloom as the major (70–80%) source of the organic carbon that decomposed and ultimately led to bottom water hypoxia. Within the Changjiang River plume, depth‐integrated net biological production in the water column was 1.8 g C m−2 d−1, indicating strong autotrophic production, which in turn led to a high respiration rate of 1.2 g C m−2 d−1 in the bottom water. During both cruises, strong surface‐to‐bottom physical and metabolic coupling was evident. In 2009, storm‐driven inputs of nutrients from elevated river discharge and strong vertical mixing helped to fuel the rapid development of a surface diatom bloom. Afterwards, stratified conditions re‐established, newly formed labile organic matter sank, and bottom water oxygen was quickly consumed to an extent that hypoxia and acidification developed. To our knowledge, the observed rate of hypoxia and acidification development (within 6 d) is the fastest yet reported for the Changjiang River plume.

Isotopic evidence for the influence of typhoons and submarine canyons on the sourcing and transport behavior of biospheric organic carbon to the deep sea

Export of biospheric organic carbon from land masses to the ocean plays an important role in regulating the global carbon cycle. High-relief islands in the western Pacific are hotspots for such land-to-ocean carbon transport due to frequent floods and active tectonics. Submarine canyon systems serve as a major conduit to convey terrestrial organics into the deep sea, particularly during episodic floods, though the nature of ephemeral sediment transportation through such canyons remains unclear. In this study, we deployed a sediment trap in southwestern Taiwan's Gaoping submarine canyon during summer 2008, during which Typhoon Kalmaegi impacted the study area. We investigated sources of particulate organic carbon and quantified the content of fossil organic carbon (OCf) and biospheric non-fossil carbon (OCnf) during typhoon and non-typhoon periods, based on relations between total organic carbon (TOC), isotopic composition (δ13C, 14C), and nitrogen to carbon ratios (N/C) of newly and previously reported source materials. During typhoons, flooding connected terrestrial rivers to the submarine canyon. Fresh plant debris was not found in the trap except in the hyperpycnal layer, suggesting that only hyperpycnal flow is capable of entraining plant debris, while segregation had occurred during non-hyperpycnal periods. The OCnf components in typhoon flood and trapped samples were likely sourced from aged organics buried in ancient landslides. During non-typhoon periods, the canyon is more connected to the shelf, where waves and tides cause reworking, thus allowing abiotic and biotic processes to generate isotopically uniform and similarly aged OCnf for transport into the canyon. Therefore, extreme events coupled with the submarine canyon system created an efficient method for deep-sea burial of freshly produced organic-rich material. Our results shed light on the ephemeral transport of organics within a submarine canyon system on an active tectonic margin.

Numerical research on evolvement of submarine sand waves in the Northern South China Sea

Submarine sand waves, vital to seabed stability, are an important consideration for oceanic engineering projects such as oil pipe lines and submarine cables. The properties of surface sediment and the evolvement of submarine sand waves in a specified area in the South China Sea are studied using both a hydrological model and field observational data. The bottom flow field data between 2010 and 2011 in the study area are simulated by the Regional Ocean Model System (ROMS). The migration of submarine sand waves is calculated using Rubin’s formula along with typhoon data and bottom flow field data, which allows for the analysis of sand wave response under the influence of typhoons. The migration direction calculated by Rubin’s formula and bottom flow are very similar to collected data. The migration distance of different positions is between 0.0 m and 21.8 m, which reciprocates cumulatively. This shows that Rubin’s formula can predict the progress of submarine sand waves with the bottom flow simulated by ROMS. The migration distances of 2 sites in the study area are 2.0 m and 2.9 m during the typhoon “Fanapi”. The proportion of the calculated migration distance by the typhoon is 9.17% and 26.36% of the annual migration distance, respectively, which proves that the typhoon can make a significant impact on submarine sand waves.

Influence of typhoon on fatigue life of beam structure by constant acceleration measurement

Influence of typhoon on fatigue life of beam structure by constant acceleration measurement

DUNE RESTORATION EXPERIMENTS DURING A TYPHOON SEASON ON TAIWAN?€(TM)S SI-CAO COAST

The restoration of coastal dunes, a common form of soft protection, can not only save considerable construction and maintenance costs but also facilitate the maintenance of coastal ecological environments and natural landscapes. Taiwan sustains frequent typhoons and its Si-Cao coast has been seriously affected by previous storms. Restoration of the sand dunes of the Si-Cao coast is necessary and urgent, and the influence of typhoons should be fully considered in dune restoration. Therefore, four test sets were created to perform dune restoration experiments in the northern section of the Si-Cao coast by using different methods, materials, and layouts. We compared topographical and vegetation survey results preceding and following four typhoons, and used this information to identify suitable construction methods for typhoon-affected dunes. These results indicated that artificial vegetation did not perform ideally because the growth of vegetation was slow under the influence of typhoons. Oyster bamboo racks were found to have a positive effect on sand trapping, and provided a shelter that enabled plants to grow naturally. Sand accumulation between two fences was substantial, but moderately dispersed. After consecutive typhoons, vegetation coverage showed a downward trend in all four test sets; however, the sand fence set had the highest protective effect on vegetation. Spinifex littoreus exhibited a strong ability to resist typhoons; after a slight decrease, its coverage improved markedly. According to these results, we provide recommendations for dune restoration on the Si-Cao coast.

Water level fluctuations in Guangxi near coast caused by typhoons in South China Sea

The increasing and decreasing water level in Guangxi near the coast is mainly caused by typhoon-induced storm surges. The maximum values of increase and decrease recorded at the Beihai Station over the last 42 years are 1.45 m and -1.87 m. The water level first decreases and then increases in Guangxi near the coast. Apart from the direct influence of typhoons, the westward coastal-trapped wave along the Guangdong continental shelf is also greatly affected. A portion of the westward coastal-trapped wave passed directly through the Qiongzhou Strait into Beibu Gulf, and the other portion passed through the southern part of Hainan Island into the Beibu Gulf. On July 2, 2001, the westward coastal-trapped wave caused by Typhoon Durian induced a strong westward flow along the Guangxi coast, and the geostrophic flow velocity on the surface reached 92cm/s. On July 6, 2001, though Typhoon Utor landed at the northern part of the Pearl River Estuary, it widely induced a 20-cm increase in the water level in Guangxi near the coast on July 8. Apart from the direct and indirect influences of typhoons on the fluctuation of the water level along the Guangxi coast, the particular topography and atmospheric gravity wave also have affect the fluctuation of the water level.

Effect of typhoon on atmospheric aerosol particle pollutants accumulation over Xiamen, China

Great influence of typhoon on air quality has been confirmed, however, rare data especially high time resolved aerosol particle data could be used to establish the behavior of typhoon on air pollution. A single particle aerosol spectrometer (SPAMS) was employed to characterize the particles with particle number count in high time resolution for two typhoons of Soulik (2013) and Soudelor (2015) with similar tracks. Three periods with five events were classified during the whole observation time, including pre – typhoon (event 1 and event 2), typhoon (event 3 and event 4) and post – typhoon (event 5) based on the meteorological parameters and particle pollutant properties. First pollutant group appeared during pre-typhoon (event 2) with high relative contributions of V – Ni rich particles. Pollution from the ship emissions and accumulated by local processes with stagnant meteorological atmosphere dominated the formation of the pollutant group before typhoon. The second pollutant group was present during typhoon (event 3), while typhoon began to change the local wind direction and increase wind speed. Particle number count reached up to the maximum value. High relative contributions of V – Ni rich and dust particles with low value of NO3−/SO42− was observed during this period, indicating that the pollutant group was governed by the combined effect of local pollutant emissions and long-term transports. The analysis of this study sheds a deep insight into understand the relationship between the air pollution and typhoon.

Wave climatological analysis in the East China Sea

The ERA-40 and ERA-Interim datasets from ECMWF (European Centre for Medium-Range Weather Forecasts) are used to study the wave and wind climate in the East China Sea (ECS). The temporal and spatial variablities in the wave and wind fields on multiple scales from the intraseasonal to decadal are discussed in detail. The results show that the wave height and the wind speed are highly correlated, especially in winter. For interannual and decadal scale, the wind and wave in the ECS is strongly influenced by the ENSO and PDO with the negative correlation. The trend spatial distributions of the mean state and extreme events are presented with wave height increase by 0.005–0.01ma−1 in most of the ECS from 1979 to 2014. The influence of typhoon on the extreme wave is significant. Vector empirical orthogonal function (VEOF) methods are used to analyze the primary three modes of wave and wind variability. Because the monthly values are filtered the fluctuation with period shorter than 14 months before VEOF analysis, the three modes presents interannual variations. The first mode is presented as the wind blowing from land to sea or from sea to land. The second mode reflects the asymmetry of winter and summer monsoon for wind and wave. And the third mode presents as a cyclone located near 28°N which caused by a cyclonic eddy existing in the north of the ECS. The waves are further categorized based on quasi-wave age. The wind waves and swell distributions display obvious differences in different seasons. The wind waves are found to be dominated in autumn and winter in the ECS.

Selection of Methods for Predicting Tidal Levels with a Typhoon Surge Effect

ABSTRACT Yuan, H.; Tan, M., and Wang, W., 2015. Selection of methods for predicting tidal levels with a typhoon surge effect. Accurate prediction of tidal level with strong meteorological effects is very important for human activities in oceanic and coastal areas. Under severe weather, such as typhoons, the contribution of non-astronomical components to tidal level may be as significant as that of astronomical components. The traditional harmonic analysis method and other models based on the analysis of astronomical components do not work well in these situations. The objective of this paper is to select an effective method for predicting the tidal level under the influence of typhoons at Luchaogang, China. The linear regression, back-propagation (BP) and radial basis function neural network methods are compared. Based on the typhoon data and tidal-level data gathered from Pudong Hydrological Bureau, seven parameters of typhoon are extracted and employed as input parameters while the corresponding tidal-l...