Horizontal wind shear are the horizontal winds around a cyclone. When these winds have lower speeds they help a cyclone grow in strength and when they have higher speeds they make it dissipate
Cyclone Freddy, which has been active for 32 days over the south Indian Ocean, is now the longest-lived tropical cyclone on record. It has already made two landfalls and is likely to make another.
Cyclone Freddy has had a major impact on people in Madagascar and Mozambique due to the impact of its swift winds and also the accompanying rainfall. It has killed 21 people and displaced thousands of people causing a crisis in both countries.
The cyclone formed (February 6, 2023) around the northern coast of Australia (traversed more than 9,600 km) and made its first landfall along the south-eastern coast of Madagascar (February 21) where its winds and rainfall caused significant damage.
It then crossed over into the Mozambique Channel, gained some energy and made a second landfall along the Mozambique coast (February 24). After this, the storm system spent several days over Mozambique and Zimbabwe causing rainfall.
Freddy is now moving towards Mozambique again and would intensify, according to the World Meteorological Organization (WMO). Freddy’s record for the longest-lived cyclone is still unofficial as the WMO has to analyse the cyclone’s track and intensities over the period to be able arrive at this conclusion.
Freddy has also experienced rapid intensification the highest number of times. When the tropical cyclone undergoes rapid intensification it gains wind speeds of 56 kilometers per hour in 24 hours. Freddy has done this six times which is a record.
Horizontal wind shear are the horizontal winds around a cyclone. When these winds have lower speeds they help a cyclone grow in strength (as in Freddy’s case) and when they have higher speeds they make it dissipate.
The winds also pushed up warm sub-surface waters which helped it rapidly intensify multiple times. Around 90 per cent of the warming due to human-induced greenhouse gasses is absorbed by the oceans, increasing their heat content and has made them the warmest they have ever been, according to the latest data from WMO.
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