Typhoon Soudelor Would Have Been Stronger If Not for El Nino

Typhoon Soudelor Would Have Been Stronger If Not for El Nino
Photo Credit: Windyty wind forecast @Windyty.com截圖

What you need to know

There is a negative feedback mechanism to prevent typhoons from overdevelopment. This happened to typhoon Soudelor, and the forthcoming typhoon Goni also belongs to this kind of weakened typhoon.

This is year of the El Nino. According to previous research, the relatively warm seawater is favorable for the development of typhoons under the circumstances of El Nino. Typhoons also grow stronger than usual when formed further away from land.

But now statistics shows water structure under the sea can help brake the forming of a typhoon. In other words, if it were not for the El Nino, typhoon Soudelor that developed from a mild to severe typhoon within only 24 hours could have caused more damage.

China Times reports, the forming locations of typhoons will shift southeastward in years of El Nino. The Warm Pool(1) will also extend to the southeast so the objective conditions are suitable for a typhoon to form. But according to the Accumulated Cyclone Energy(ACE), the intensity and amount of typhoons in El Nino years have not changed significantly. The reason lies in the underwater structure that has long been ignored by scholars.

Zheng Zhe-wen, associate professor at the Institute of Marine Environmental Science and Technology at National Taiwan Normal University, says the east wind diminishes in El Nino years so the warm seawater moves eastward. The water at the bottom of the sea then shifts upward to supplement the surface of the sea, and can thus properly adjust the surface temperature of the Pacific Ocean warmed by the El Nino and stop typhoons from growing endlessly.

Yam News reports, the intensity of the typhoon in El Nino years enhances by 50 percent compared to normal years, but the average intensity only increases by 27 percent due to the hydrothermal variation under the sea.

Zheng says, people pay little attention to things happening under the water. In fact, there is a negative feedback mechanism to prevent typhoons from overdevelopment. This happened to typhoon Soudelor, and the forthcoming typhoon Goni also belongs to this kind of weakened typhoon.

Liberty Times reports, research conducted by Taiwan and U.S. scholars found that even if the surface environment of the sea is suitable for developing terrifying typhoons, the undersea water still can refill and cool down the surface water in time and suppress its intensity and amount. This system is just like the mother of the earth, Gaia(2), self-repairing and protecting the balance from losing control.

The research added the concept of the Gaia-Like Process hypothesis, which was introduced in 2003. It states everything on the planet has the ability to balance each other so that human beings will not suffer from the severe revenge of nature.

This research was published this year on the July issue of the Nature science magazine. Zheng says humans should appreciate the repair system of Gaia and protect the planet.

(1) Waters with a surface temperature over 28 Celsius degree. There are three major warm pools on the planet, including the western hemisphere warm pool, Indian Ocean warm pool and West Pacific warm pool. The West Pacific warm pool has the highest temperature and accumulates the most heat in the waters among the three.

(2) Gaia is the Mother of the Earth in Greek mythology. She is the mother of all gods and creatures in the universe.

Translated by June
Edited by Olivia Yang

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