Three Tropical Cyclones Lurk Near Africa and One Has Set a New Rapid Intensification Record
Signals Summary: As climate change causes oceans to warm, surface waters have more energy to convert to hurricane winds, which scientists say is likely increasing the frequency of intense hurricanes, cyclones and typhoons.
The tropics are getting crowded once again during this record season in the Indian Ocean as a phenomenon similar to a strong El Niño keeps waters warm near Africa.
Three hurricanes – or tropical cyclones, as they are called in that part of the world – continue to spin in the western Indian Ocean as of late Thursday.
This week's tropical cyclone triplets have been spawned by an intersection of very favorable climate and weather conditions.
First, the part of the world where these cyclones have spun up is experiencing something akin to El Niño in the Indian Ocean – the positive mode of a feature called the Indian Ocean Dipole (IOD).
The positive IOD has spread far-above-average water temperatures over much of the western Indian Ocean and Arabian Sea. These warmer waters are not only more favorable for hurricane development – they also support increased rainfall for parts of eastern Africa.
Another strong climate pattern has assisted these cyclones: A favorable phase of the Madden-Julian Oscillation, or MJO, is sweeping eastward across the Indian Ocean.