沿海海洋对台风反应强烈,使他们成为受影响最严重的地区之一。然而,由于现场调查很少,我们对台风强度和运动路径对海洋动力过程和生态环境因素的影响的理解仍然有限,特别是在台风事件期间在海湾进行连续的野外观测。这项研究通过连续调查(间隔5天)在湛江湾的十次航行中调查了双水同位素,与两个不同强度的台风和着陆轨迹(左侧和右侧)有关。台风过后,水体混合加剧,坚持了几个星期,持续时间取决于台风的强度。在台风期间,淡水对营养负荷的贡献大幅增加;然而,强台风的贡献高于弱台风。较弱的台风Lionrock,降落在海湾的左侧,由于台风引起的陆上风,可以增强海洋前沿,导致高盐度海水侵入海湾,并将污染物留在海湾。然而,当更强的台风Chaba以更大的力量降落在右侧时,台风期间逆时针风应力引起的海上风导致更多的海水流向下海湾。这防止了海洋前缘的形成,并通过其流体动力学过程在污染物中起到稀释作用。这主要是由于台风的登陆轨迹直接影响湛江湾海水的流向,而台风的强度进一步放大了这些流动模式。这项研究表明,台风运动的轨迹,而不是它们的强度或陆地径流,在台风事件期间,在管理沿海海湾的海洋动态和养分供应方面发挥着至关重要的作用。
Coastal oceans are highly responsive to
typhoons, making them one of the most affected regions. However, our understanding of the impact of typhoon intensity and movement path on marine dynamic processes and eco-environmental factors remains limited because there are very few on-site investigations, especially continuous field observations in the bay during typhoon events. This study investigated dual water isotopes through a continuous survey (with a 5-day interval) during ten cruises in Zhanjiang Bay, associated with two
typhoons of varying intensities and landing tracks (left and right sides). After
typhoons, the water mass mixing intensified and lasted for several weeks, depending on the intensity of
typhoons. During the typhoon periods, there was a considerable increase in contributions from freshwater to nutrient loads; however, this contribution was higher from the stronger typhoon than the weaker one. The weaker Typhoon Lionrock, which landed on the left side of the bay, enhanced the ocean front due to onshore winds induced by the typhoon, causing intrusion of high-salinity seawater into the bay and retaining pollutants in the bay. However, when stronger Typhoon Chaba landed on the right side, offshore winds induced by counterclockwise wind stress during the typhoon resulted in more seawater flowing toward the lower and outer bay. This prevented the forming of an ocean front and played a dilution role in pollutants through its hydrodynamic process. This was primarily due to the fact that the landing trajectory of typhoons directly influenced the direction of seawater flow in Zhanjiang Bay, while the intensity of
typhoons further amplifies these flow patterns. This study suggests that tracks of typhoon movement, rather than their intensity and terrestrial runoff, play a crucial role in governing marine dynamics and nutrient supplies in coastal bays during typhoon events.