PANAJI
Monsoon patterns in India have become increasingly unpredictable and erratic in recent years, and Goa is no exception.
The coastal State, of late, has experienced rainfall every month from this calendar year with existing cyclonic circulation and low pressure area, expected to bring in more rains for the State. The alteration has been mainly driven by the accelerating rate of climate change.
It was in 2021, when Goa set the record of receiving rainfall in the entire calendar year -- January to December -- and the trend continued thereafter with some or the other rain gauge recording showers in all 12 months.
This year too, the pre-monsoon season starting from March, followed by the monsoon season till September and the post-monsoon season in October-November is experiencing rainfall activities along with thunderstorms and lightening.
According to a study ‘Decoding India’s Changing Monsoon Patterns: A Tehsil-level Assessment’, by the Council on Energy, Environment and Water (CEEW) there has been a statistically significant increasing trend in the Northeast Monsoon rainfall along the tehsils of Goa and Maharashtra on the west coast since 2021. “This increase could partially be attributed to the cyclonic activities in the Arabian Sea and Bay of Bengal,” the study said.
This year too, as per IMD Goa, there exists a cyclonic circulation along Bay of Bengal and Arabian Sea and low pressure area in southwest region, bringing in rainfall for the State.
Recently, National Institute of Oceanography (NIO) Director Prof Sunil Kumar had attributed the increased incessant rainfall activities to the climate change. “Climate change has started showing its impact by way of extended monsoon periods in Goa, excessive rainfall, above normal rainfall….,” he had said.
Former NIO scientist Dr Ramesh Kumar said that North east monsoon phenomenon had set over peninsular India, the day monsoon withdrew from the Indian subcontinent. “Cyclonic circulation in the South-eastern Arabian Sea is a reason why we see rainfall post monsoon season,” he said.
Kumar said that this year, the southwest monsoon- June to September, behaved in a peculiar fashion. Without any remote force such as El Nino or La Nina in the eastern equatorial Pacific Ocean and the Indian Ocean Dipole in the Indian Ocean, the monsoon rainfall was excess over the Indian subcontinent and of Goa too, he added.
“The present trend of monsoon across all months can be attributed to climate change. We have even seen situations, where consecutive 22 months, rainfall was recorded in Goa,” he said.
The four-month long annual southwest monsoon season this year ended on surplus note, with the State recording 46 per cent excess rains. This season also recorded the highest rainfall of 4400.7 mm (173.25 inches) as against the average of 3007.8mm.
The post monsoon currents are active till now with the State receiving 101 per cent excess rains from October till date. The total rainfall recorded as on date is 374.6 mm as against the normal 185.9mm.
A former Goa IMD director cum scientist explained that the reason for rainfall activities in winter is the persistence of easterly systems over the region which occasionally resulted in increased moisture at lower levels of atmosphere and resulted into rainfall.
