पर्यावरण

Chennai, southern Andhra brace as Michaung gets set to barrel east coast

Low-lying Chennai, with its rivers, waterbodies and encroachment, has been victim to urban flooding in 2015 and 2021

Cyclone Michaung, which is expected to pass through Chennai on December 4 and make landfall on December 5 somewhere between Machilipatnam and Nellore (both in south Andhra Pradesh), will cause heavy rains accompanied by winds clocking 90-100 kilometres per hour (kmph). Chennai, Nellore, Machilipatnam, Vijayawada — and to some extent Hyderabad and Warrangal — will be severely affected.

Cyclonic Storm “MICHAUNG” (pronounced as MIGJAUM) over the southwest Bay of Bengal moved northwestwards with a speed of 5 kmph during the past six hours and lay centred at 8.30 am on December 3 near Latitude 11.5°N and Longitude 82.4°E, according to the India Meteorological Department bulletin issued at 12 noon.

It was about 290 km east-southeast of Puducherry, 290 km southeast of Chennai, 420 km southeast of Nellore, 530 km south-southeast of Bapatla and 530 km south-southeast of Machilipatnam.

It is likely to continue moving northwestwards, intensify further and reach the West Central Bay Of Bengal off south Andhra Pradesh and adjoining north Tamil Nadu coasts by December 4 forenoon.

Thereafter, it would move nearly northwards, almost parallel and close to the south Andhra coast, and cross it between Nellore and Machilipatnam during the afternoon of December 5 as a Severe Cyclonic Storm with a maximum sustained wind speed of 90-100 kmph, gusting to 110 kmph.

Michaung is most likely to cause severe rains and winds in all four cities on its course — Chennai, Machilipatnam, Nellore and Vijayawada. North Coastal Tamil Nadu and Puducherry will experience light to moderate rainfall at most places.

Heavy to very heavy rainfall at a few places and isolated extremely heavy falls is likely on December 3 and 4. Isolated heavy rainfall is likely on December 5.

Chennai and Andhra coasts

Chennai, located on the Coramandel Coast of the Bay of Bengal, has a flat terrain. Most of its areas have an average elevation of barely 2.0 metres above mean sea level. Three rivers (Cooum, Adyar and Kosasthalaiyar), two major water courses (Buckingham Canal and Otteri Nullah) and several waterbodies (‘tanks’) lie within or the vicinity of Chennai.

Its topography and erratic climatic conditions have made Chennai witness disasters on several occasions ranging from cyclones, monsoonal floods due to heavy downpours, earthquakes and even tsunamis. 

The Mayor of Chennai, Priya Rajan, told Down To Earth (DTE): “There are areas below mean sea level, which makes it difficult to manage inundation during heavy rainfall. Moreover, disasters are beyond our control and capabilities wherein we can reduce the risk and prevent losses to certain extent.”

Rajan added that Greater Chennai Corporation as the jurisdictional disaster management authority has the foremost responsibility to effectively coordinate disaster mitigation and response arrangements.

“This is why we have put together The City Disaster Management Plan (CDMP) that provides a broad framework covering the implementation of mitigation of damage and effect of the disasters in Chennai city,” the mayor observed.

The Greater Chennai Corporation Control Room serves as Chennai’s Emergency Operations Centre, which monitors the weather system on realtime basis. “Just like in 2015 and 2021, the Control Room has begun sending out advisories and reaching out to every ward in the Corportion to brace for the impact,” the mayor said.

Senior writer and editor, Ananthakrishnan told DTE: “Two landmark deluges in Chennai are those that occurred in 2015 and 2021. In both cases, the city has seen widespread destruction. The government has taken steps to revamp the drain system in the city but it is not fully in place.”

He added that in those places where the drain system has been completed, it has not been maintained. Debris and municipal waste could be causing blocakges in several spots.

“The rain caused by the Michaung cyclone can create problems in those parts of Chennai where the drains are not yet operational and in those areas that are yet to be connected to the newly revamped drain network. In another scenario, the boom in real estate is now eating into the marshlands of Chennai city, mainly the Pallikaranai marsh, where most of the city’s stormwater soaks into,” Ananthakrishnan noted.

According to officials in the civil engineering division of the Corporation, ward offices and officers have been sensitised to the effects of the cyclone and the standard operating systems have been prepared for functional levels.

In coastal Andhra Pradesh, the predictions are more grim: Light to moderate rainfall at most places, heavy to very heavy rainfall at a few places, with extremely heavy rainfall at isolated places over south coastal Andhra Pradesh on December 3.

There will be heavy to very heavy rainfall at a few places with extremely heavy rainfall at isolated places over coastal Andhra Pradesh and Yanam (enclave of Puducherry on the Andhra coast) on December 4 and 5.

The city municipal councils of Machilipatnam and Nellore have issued alert for both days and issued special advisories for fisherfolk not to venture into the sea for fishing expeditions. The district administration of Krishna district has advised people not to visit beaches and, as far as possible, remain within the safety of their homes. Police, home guards and fire department have been put on alert.   

Kalkuli Vittal Hegde, an authority on rainforests and cyclonic circulations, told DTE:

In 2021, there had been 26 cyclones in the South Asian rain system according to a study I did. Those bigger and with more power have been named. Smaller ones have been dismissed as upper area circulations and assigned some insignificant nomenclature. But so many cyclones mean that there is a serious change in the weather as we know it.

Hegde’s study of 125 years of monsoons and cyclonic systems indicates that the surface temperature of the sea was increasing and as a result, the wind was picking up more water contents. The result is intense rains and flooding.  




Source link

Most Popular

To Top
What would make this website better?

0 / 400