Of all the hazards that hurricanes bring, storm surge is the greatest threat to life and property along the coast. It can sweep homes off their foundations, flood riverside communities miles inland, and break up dunes and levees that normally protect coastal areas against storms.
As a hurricane reaches the coast, it pushes a huge volume of ocean water ashore. This is what we call storm surge.
This surge appears as a gradual rise in the water level as the storm approaches. Depending on the size and track of the hurricane, storm surge flooding can last for several hours. It then recedes after the storm passes.
Water level heights during a hurricane can reach 20 feet or more above normal sea level. With powerful waves on top of it, a hurricane’s storm surge can cause catastrophic damage.
What determines how high storm surge gets?
Storm surge begins over the open ocean. The strong winds of a hurricane push the ocean waters around and cause water to pile up under the storm. The low air pressure of the storm also plays a small role in lifting the water level. The height and extent of this pile of water depend on the strength and size of the hurricane.
As this pile of water moves toward the coast, other factors can change its height and extent.
If a coastal area has a sea floor that gently slopes away from the coastline, it’s more likely to see a higher storm surge than an area with a steeper drop-off. Gentle slopes along the Louisiana and Texas coasts have contributed to some devastating storm surges. Hurricane Katrina’s surge in 2005 broke levees and flooded New Orleans. Hurricane Ike’s 15- to 17-foot storm surge and waves swept hundreds of homes off Texas’ Bolivar Peninsula in 2008. Both were large, powerful storms that hit in vulnerable locations.
The shape of the coastline can also shape the surge. When storm surge enters a bay or river, the geography of the land can act as a funnel, sending the water even higher.
Other factors that shape storm surge
Ocean tides – caused by the gravity of the moon and sun – can also strengthen or weaken the impact of storm surge. So, it’s important to know the timing of the local tides compared to the hurricane landfall.
At high tide, the water is already at an elevated height. If landfall happens at high tide, the storm surge will cause even higher water levels and bring more water further inland. The Carolinas saw those effects when Hurricane Isaias hit at close to high tide on Aug. 3, 2020. Isaias brought a storm surge of about 4 feet at Myrtle Beach, South Carolina, but the water level was more than 10 feet above normal.
How storm surge and high tide add up to coastal flooding.(The COMET Program/UCAR and National Weather Service)
Sea level rise is another growing concern that influences storm surge.
As water warms, it expands, and that has slowly raised sea level over the past century as global temperatures have risen. Freshwater from melting of ice sheets and glaciers also adds to sea level rise. Together, they elevate the background ocean height. When a hurricane arrives, the higher ocean means storm surge can bring water further inland, to a more dangerous and widespread effect.
C | 作为法国夺得2018世界杯冠军时的中场主力,博格巴在最近两任曼联主帅索尔斯克亚和朗尼克手下也没有发挥出应有的水平。但在尤文,博格巴留下的回忆很美好。尤文在公告中回忆道:“2016年,我们在经历了美好的四年后走向分别。
D | 那些年里,一位才华横溢的法国男孩在十几岁的年龄上演一线队首秀,不到一个月就收获处子球。那些年里,我们学会当他在禁区外瞄准时要屏住呼吸,因为进球随时可能发生,确实也时常发生。在四个意甲赛季里,博格巴14次在禁区外远射进球。
E | ”博格巴上次在尤文效力时,身披6号球衣,当时的中场搭档包括皮尔洛、比达尔、马尔基西奥,他们一起帮助尤文打进2014-2015赛季欧冠决赛,可惜输给巴塞罗那,巴萨的“MSN组合”梅西、苏亚雷斯、内马尔当时如日中天。第一次效力尤文期间,博格巴出场177次,攻入34球并有40次助攻,4次帮助尤文夺得意甲冠军。博格巴的职业生涯,简单总结就是坑曼联、让尤文受益。博格巴第一次由曼联加盟尤文是在2012年夏天,作为曼联青训产品,19岁的他自由转会投奔尤文。当时的曼联老帅弗格森对博格巴非常不满意,认为他不尊重曼联对他的培养。2016年8月8日,博格巴从尤文回归曼联,1.05亿欧元的转会费创下当时的世界纪录。六年后,博格巴与曼联再次合同期满,又一次以自由球员的身份加盟尤文。
F | 尤文俱乐部在公告中感叹道:“博格巴回到都灵城,他离开时是一个男孩,他归来时是一位冠军、一个男人。但有一件事始终未变,那就是对再度书写俱乐部历史中辉煌篇章的渴望,欢迎回家,保罗(博格巴)!”这次回来,博格巴在尤文的年薪约为800万欧元,他在曼联的年薪约为1500万欧元。博格巴现在很开心,他拍摄视频向中国球迷问好:“中国的球迷们你们好,我回都灵城只做三件事——获胜、获胜还是获胜。
Current article:http://934nemr.cuancuguanzhongnieqinyazhun.cyou/vguis/3ffubi.html