Cyclone Biparjoy intensifies into very severe cyclonic storm, affects monsoon intensity

New Delhi: Cyclone ‘Biparajoy’, the first storm to hit the Arabian Sea this year, rapidly intensified into a very severe cyclonic storm on Wednesday night, with meteorologists marking the beginning of ‘light’ monsoon over Kerala and further south peninsula under its influence. Weak’ progress predicted. ,

The India Meteorological Department (IMD) had said on Wednesday morning that conditions are favorable for the onset of monsoon over Kerala within two days. However, meteorologists said that the cyclone is affecting the intensity of the monsoon and the onset over Kerala will be ‘mild’. The MeT office said the very severe cyclonic storm would further intensify and move north during the next three days.

In a tweet on Thursday morning, the IMD said, “VSCS Biparjoy lay centered over east-central Arabian Sea at 0530 hrs IST on June 08, near latitude 13.9N and longitude 66.0E, about 860 km west-southwest of Goa, About 910 km southwest of Mumbai, it will further intensify and move north-northwest.”

VSCS BIPARJOY lay centered over east-central Arabian Sea at 0530 hrs IST on June 08, near latitude 13.9N and longitude 66.0E, about 860 km west-southwest of Goa, 910 km southwest of Mumbai, and Will intensify and move towards north-northwest. pic.twitter.com/6HiSydw2qI— India Meteorological Department (@Indiametdept) June 8, 2023

However, the IMD has not yet predicted any major impact on countries adjoining the Arabian Sea including India, Oman, Iran and Pakistan.

Meteorologists say that the tentative track of the system will be in the north direction but at times storms defy the predicted track and intensity.

Cyclone Biparjoy undergoing ‘rapid intensification’

Forecasting agencies said the storm is undergoing “rapid intensification”, from a mere cyclonic circulation to a very severe cyclonic storm in just 48 hours, defying earlier predictions.

Atmospheric conditions and cloud mass indicate that the system is likely to maintain the strength of a Very Severe Cyclonic Storm till June 12.

Scientists say that cyclonic storms in the Bay of Bengal and the Arabian Sea are rapidly intensifying and may maintain their intensity for longer periods due to climate change.

According to a study titled ‘Changing Status of Tropical Cyclones over the North Indian Ocean’, the frequency, duration and intensity of cyclones in the Arabian Sea have increased by about 20 per cent in the post-monsoon period and 40 per cent in the pre-monsoon period. Monsoon season.

There has been a 52 per cent increase in the number of cyclones in the Arabian Sea, while there has been a 150 per cent increase in very severe cyclones.

Roxy Mathew Cole, Climate Scientist, “The increase in cyclone activity in the Arabian Sea is linked to rising ocean temperatures and increased moisture availability under global warming. The Arabian Sea used to be cold, but is now a warm pool. ” Indian Institute of Tropical Meteorology said.

“Oceans have already warmed due to climate change. In fact, a recent study suggests that the Arabian Sea has warmed by about 1.2°C since March, thus increasing the rapid intensification of the system (cyclone The conditions are very favorable for (Bipajoy) so it has the potential to maintain strength for a long period,” said Raghu Murtugudde, Professor, Department of Atmospheric and Oceanic Sciences, University of Maryland and IIT Bombay.

Monsoon to remain ‘weak’ after knocking over Kerala

Skymet Weather vice-president (climate and meteorology) Mahesh Palawat said clouds are concentrated around the system and not enough moisture is reaching the Kerala coast.

Though the criteria for the onset of monsoon may be met in the next two days, it will not be a bang.

He said that after knocking over Kerala, the monsoon will remain weak till it weakens around June 12.

Skymet Weather on Tuesday had said, “Powerful weather systems in the Arabian Sea may spoil the inland progress of the monsoon. Under their influence, the monsoon current may reach the coastal parts, but will struggle to move beyond the Western Ghats.” ”

A senior IMD scientist said that the southern peninsula will receive rain under the influence of a cyclonic storm and a low pressure system developing in the Bay of Bengal. However, further progress of Monsoon over the southern peninsula will take place after the cyclone subsides.

“It will not be a case of a classic monsoon onset that meets all the given criteria. We will have scattered rain along the West Coast strip, but no inland penetration and widespread rain,” Cole said.

The southwest monsoon generally enters Kerala on 1 June with a standard deviation of about seven days. In mid-May, the IMD said the monsoon could hit Kerala by June 4.

Skymet predicted the onset of monsoon over Kerala on June 7 with an error margin of three days.

According to IMD data, over the past 150 years, the monsoon onset date over Kerala has varied widely, with the earliest being May 11, 1918, and the latest being June 18, 1972.

The southwest monsoon had arrived last year on May 29, 2021, June 3, 2020, June 1, 2019, June 8 and May 29 in 2018.

Research shows that delayed onset of monsoon over Kerala (MOK) does not necessarily mean delayed onset of monsoon over northwest India.

However, delay in MoK is generally associated with delay in commencement, at least in southern states and Mumbai.

Scientists say that even the delayed MoK does not affect the total rainfall over the country during the season.

The IMD had earlier said that despite the development of El Nino conditions, India is expected to receive normal rainfall during the southwest monsoon season.

Normal to less than normal rainfall is expected over Northwest India. Normal rainfall is expected to be 94-106 per cent of the long period average of 87 cm over East and Northeast, Central and South Peninsula.

Rainfall below 90 per cent of the long period average is considered ‘deficit’, 90 per cent to 95 per cent ‘below normal’, 105 per cent to 110 per cent ‘above normal’ and more than 100 per cent is considered ‘deficit’. considered ‘low’. The percentage is ‘excess’ rainfall.

Normal rainfall is critical to India’s agricultural landscape, with 52 per cent of the net cultivated area dependent on it. It is also important for refilling reservoirs important for drinking water apart from power generation across the country.

Rainfed agriculture accounts for about 40 percent of the country’s total food production, making it a significant contributor to India’s food security and economic stability.