Unusually balmy Indian Ocean temperatures were a major reason for the total lack of Pacific typhoons in July 2020 — an unprecedented absence in 55 years of record-keeping.
Like hurricanes in the Atlantic Ocean, typhoons in the Northwestern Pacific can wreak destruction on coastal areas. But in July last year, not one typhoon made its way through the region. Such a deficit has not been recorded since satellites began monitoring tropical cyclone activity in 1965.
Liguang Wu at Fudan University in Shanghai and Chao Wang at Nanjing University of Information Science and Technology, both in China, and their colleagues analysed oceanic and atmospheric data in search of an explanation for the calmer-than-normal skies. They found that surface temperatures in the Indian Ocean in July 2020 were the highest on record, leading to a high-pressure atmospheric system that suppressed typhoon formation. Anomalous ocean temperatures in the Atlantic and Pacific oceans also contributed.
Because climate change is warming the Indian Ocean faster than other tropical waters, the authors say, this lack of typhoons might become more common in future.