NEW DELHI :
Almost eleven years after Mumbai was battered by cyclone Phyan, the city is bracing for severe cyclonic storm Nisarga,which is set to cross the Maharashtra coast on Wednesday.
The India Meteorological Department (IMD) had raised a Yellow warning for north Maharashtra and South Gujarat, announcing that Cyclone Nisarga has formed in the Arabian Sea and is approaching the west coast as a ‘severe cyclonic storm’, bringing winds of 100-110 kmph gusting to 120 kmph coupled with heavy rainfall.
The forecast suggests the cyclone could make a landfall on the north Maharashtra and adjoining south Gujarat coast between Harihareshwar and Daman, close to Alibagh in Raigarh district of Maharashtra around June 3 afternoon.
In 2009, Cyclone Phyan too had followed similar track and crossed the Maharashtra coast near Alibagh. Though it had bypassed Mumbai, it caused massive damage to property in the coastal districts of Ratnagiri, Raigad, Sindhudurg, Thane and Palghar.
This time, low lying areas of Mumbai, Thane and Raigad could get inundated up to 1-1.5 kms with storm surge of about 1-2 meters height above the astronomical tides. Storm surges of 0.5-1 meter height above the astronomical tide are expected in low lying areas of Ratnagiri district during the time of landfall.
“Storm surges pose the maximum threat during cyclones. Coastal cities like Mumbai are rendered more vulnerable, because of the topography. It is an island city and the combined effect of storm surge and heavy rains at the same time, could lead to heavy flooding, especially if there is a high tide," said M.V. Ramana Murthy, director, National Centre for Coastal Research (NCCR), Chennai.
The potential of damage has been exacerbated by inadequate drainage system, reckless concretization, unplanned urban development and destruction of wetlands and Mangroves which could have helped in slowing down the inland flow of storm surges. Mithi River which is responsible for draining out water into the seas too has been reduced to an open drain and is prone to flooding during heavy rains.
The latest forecast suggests the cyclone had begun veering towards the west coast after moving northwards for a while. Heavy rains have already begun lashing the coastal areas of Karnataka and Madhya Maharashtra.
There would be heavy rains with extremely heavy falls over Konkan (Mumbai, Palgar, Thane, Raigad, Ratnagiri, Sindhudurg districts), Goa and north Madhya Maharashtra, with some places even expected to record more than 20 cm rains during next 24 hours. Normally Arabian Sea sees 1.7 cyclonic disturbances in an year, out of which usually one develops into a cyclone, mostly in the post monsoon season.
However, the intensity of these cyclones have increased over the last few decades, due to a rapidly warming Indian Ocean. Sea levels in the North Indian Ocean have also risen more compared to other oceans.
Last year, the United Nations (UN)- Intergovernmental Panel on Climate Change (IPCC) too had warned regarding the disastrous effects of climate change and rise in extreme weather events, which could pose serious threats to coastal cities like Mumbai and Kolkata.