NTNU Discloses the Secret of El Niño-Typhoon Relationship
According to previous studies, when El Niño happens, typhoons of the West Pacific will originate from the East whose warmer water can get typhoons started. Also, due to further distance from the land, it’s reasonable that during El Niño, typhoons of larger scales will occur. However, the data shows that during El Niño, the intensity of typhoons is the same as in non- El Niño conditions. Scholars has found the negative process of typhoon during El Niño and disclosed the development of typhoon intensity. The article has been published on the July issue of Nature-Scientific Reports.
The research was conducted by Associate Professor Cheng Chih-wen from the Institute of Marine Environmental Science and Technology, NTNU, chair of department of Atmospheric Sciences Lin I-I from NTU, and Professor Wang Bin from the University of Hawaii. They have spent 3 years studying the past 50 years of typhoon data in order to discover El Niño-Typhoon relationship. Moreover, they borrowed the Gaia-hypothesis which may explain the missing-link of other typhoon researchers.
Proposed in the early 1970's, the Gaia hypothesis suggests that our planet earth has a self-regulating ability to maintain a stable condition for life. Tropical cyclone (TC) is one of the earth's most hazardous disasters; it is intriguing to explore whether 'Gaia-like' processes may exist in nature to regulate TC activities. El Niño can shift the forming position of the Western Pacific typhoons away from land. This shift enables typhoons to travel longer distances over ocean and is known to be a positive process to promote TCs to achieve higher intensity. What is neglected, however, is that there co-exists a negative process. This 'worsen' ocean pre-condition can effectively reduce ocean's energy supply for typhoon intensification during typhoon-ocean interaction. The researchers found this an elegant, 'Gaia-like' process demonstrating nature's self-regulating ability. Though during El Niño, typhoons can take advantage of the longer travelling distance over ocean to achieve higher intensity, nature is also providing a damper to partially cancel this positive impact. Without the damper, the situation could be even worse.
The study has been published on “Nature-Scientific Reports” on July 21st, if you’d like to know more, you can refer to the article A Long Neglected Damper in the El Niño-Typhoon Relationship: a‘Gaia-Like’ Process. Sci. Rep. 5, 11103; doi: 10.1038/srep11103 (2015)