Typhoon landed in Putuo, and the "mysterious Zhoushan power" was broken? What exactly is the "Putuo barrier" that netizens are hotly discussing?

At 8:30 am on September 14, Typhoon Meihua landed on the coast of Putuo, Zhoushan, triggering a wave of discussion among netizens about the "mysterious power of Zhoushan".

For a long time, people in the free shipping area like to use "barrier" to describe Zhoushan Putuo.

There is a saying that "ever since the statue of Guanyin Bodhisattva was built on Putuo Mountain, typhoons have never entered Zhoushan Putuo Island in the past years." Of course, this is not scientifically true.

For example, Typhoon Fireworks in 2021 and Typhoon Mina in 2019 made landfall in Putuo District, Zhoushan.

According to @中国气象朋友, in the sixth month of the lunar calendar in 1996, the Nanhai Guanyin statue in Putuo Mountain, Zhoushan, Zhejiang, was completed and consecrated that year. Less than a year after the consecration, the giant typhoon 9711 landed in Zhejiang, and Putuo experienced a force 13 gale, with the tide level at Dinghai Station reaching 10.68 meters, breaking the historical record; two years later, typhoon 9806 TODD landed directly in Putuo, and Putuo Station again experienced a force 13 gust; four years later in 2000, typhoons Kai Tak, Jelawat, Pabian, and Saomai passed by Zhoushan at close range, and Putuo experienced force 10-14 gales many times.

This fully demonstrates that the Nanhai Guanyin in Putuo cannot drive away typhoons, and the so-called "Magic City Barrier" in Shanghai circulating on the Internet cannot drive away typhoons either.

Why did the "Zhoushan Putuo Barrier" leave such a deep impression on everyone? Why do we always feel that it is difficult for typhoons to land in Zhejiang and Shanghai, but they are easily "bounced away" when they reach the coast of Zhejiang and Shanghai?

The fact is: it is rare for a typhoon to land in Zhejiang, especially in northern Zhejiang or Shanghai. Because northern Zhejiang and Shanghai are at high latitudes, have short coastlines, and are located just behind the East Asian trough, the subtropical high pressure can easily break in the East China Sea, causing the typhoon to move north or turn to Japan and South Korea. Taking Shanghai as an example, since 1949 (as of 2018), there have been only 9 typhoons that have landed in Shanghai, and only 1 of them reached typhoon strength.

On July 25, 1949, Typhoon No. 4906 landed in Shanghai, the strongest typhoon in Shanghai since 1949. The solid line in the figure is the path of Typhoon No. 4906, and the dotted line is the predicted path of Typhoon Ampil, from Wenzhou Typhoon Network

Therefore, for a typhoon to land in northern Zhejiang or Shanghai, the subtropical high pressure must be extremely strong and biased to the north, and it is best if the subtropical high pressure center is directly established in Shandong or even the northeast. However, this condition only occurs once every few years. In most years, when a typhoon reaches the East China Sea, the subtropical high pressure has been unable to cope with the pressure from the East Asian trough and the typhoon and begins to break, thus allowing the typhoon to move north or east.

However, in the midsummer of 2018, the subtropical high did show a rare strong northward trend, with its center established in the Yellow Sea on July 18. It then continued to move northward to near Shandong. As a result, Typhoon Ampil finally landed directly on the coast of Chongming Island in Shanghai that year, and netizens jokingly called it breaking the "Magic City Barrier."

Zhang Qian, reporter of Orange Persimmon Interactive

Contents are compiled from @China Meteorological Enthusiasts and others