Despite 90 per cent of the southwest monsoon receding from Kerala, the State should not lower guard against another possible wave of torrential rains, the weathermen have warned the State government.
The warning came in the backdrop of the uncertainty over the possible formation of cyclonic circulations of varying severity over the seas. Scientists have observed that the low-pressure areas could be formed anytime though the State has been witnessing signs of an impending retreating (northeast) monsoon.
Experts have noticed turbulence in the Bay of Bengal, Arabian Sea and the Indian Ocean. The impact of rising temperature of the sea surface could not be predicted now. A cyclonic circulation formed over the Bay of Bengal to the south of Tamil Nadu and east of Sri Lanka is currently located near Kanyakumari. Experts said the circulation has not weakened.
The circulation, according to calculations, could cause a maximum rainfall of 13 cms in some places on Sunday.
The weather department has also noticed a well-marked low-pressure area extending from central-eastern Arabian Sea to the Karnataka coast. This could cause thundershowers till Tuesday. The State Disaster Management Authority has made all preparations based on the prediction.
The India Meteorological Department (IMD), meanwhile, said the cyclonic circulation may not cause a low-pressure area. Scientists from various agencies felt the cyclonic circulation near Kanyakumari would weaken, and hence the rainfall till then could not be precisely predicted. The presence of a minor low-pressure area off Lakshadweep would become critical when the cyclonic circulation reaches the archipelago off the Kerala coast.
Sea-powered circulations
While certain cyclonic circulation remain concentrated at one place, others move faster before fizzling off. Those circulation concentrating on one place could lead to various atmospheric pressures.
Cyclonic circulations draw energy from the seas. With the sea temperature showing an unprecedented upward trend, there would be no shortage of energy for the circulations. In such circumstances, the latent heat of condensation released by clouds could activate cyclonic storms.
Various weather monitoring organizations are closely monitoring the presence of cyclonic circulations and their direction since the climate in October is conducive for the formation of cyclones. The cyclonic storm that formed over the Arabian Sea near the confluence of the Bay of Bengal caused widespread rains, minor cloud bursts and related incidents in Kerala's eastern districts, claiming several lives. The circulation, which was initially found meek, powered cyclones over the Bay of Bengal and Arabian Sea, leading to the formation of dense clouds.
Concern over Arabian Sea
Scientists and environment experts are a concerned lot after the formation of cyclonic circulations over the Bay of Bengal, a rarity, the climate change and rising temperature of the sea surface. These circulations were noticed before the 2018 floods.
Experts observe that the frequent formation of cyclonic circulations over the Arabian Sea would have a negative impact on the environmentally fragile Kerala. If the cyclonic circulation near Kanyakumari won't cause untoward incidents, the situation would return to normal, experts felt.
The IMD, meanwhile, has predicted that the northeast monsoon would gain strength over Kerala after Monday.