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Chennai weather: Why rain paralyses normal life; how to mitigate disasters

CHENNAI: Even as Tamil Nadu capital Chennai received heavy rain with thunder since early hours of Thursday, the district saw the maximum amount of rain in a day in six years. The torrential rains and severe flooding, especially in Chennai, are becoming a nightmare for Indian cities.
So, what are the reasons for hellish conditions following torrential rain?
While Nungambakkam received 133.4mm rain till 8.30am and Meenambakkam got 53.8mm, this was the highest amount of rain the city has received in a single day in October since the 161.9mm recorded on October 18, 2014.
After the northeast monsoon commenced over the region, heavy rain and thunderstorm will continue for the next two hours, as per Met predictions.
A cyclonic circulation over Southwest Bay of Bengal off north Tamil Nadu coast persists and now extends up to 3.1 km above mean sea level. This is triggering rain and strong breeze.
Blame it on northeast monsoon and ‘climate change’
“India’s cities are unprepared for extreme weather events” like rains, droughts and cyclonic storms which are becoming more frequent and intense, Chennai-based writer and social activist Nityanand Jayaraman wrote on BBC website in 2015.
“Many parts of India suffer flooding every year during the annual monsoon rains from June to September. The northeast monsoon has been particularly vigorous over southern India and more so in Tamil Nadu state, of which Chennai is the capital,” Jayaraman wrote.
Among the key reasons of flooding leading to hellish conditions for Chennai and its suburbs were building “plans and with no regard to water flows, and without anticipating extreme weather events” on the part of planners, builders, administrators and even common people and Chennai Corporation and Chennai Metropolitan Development Authority.
Illegal constructions, rampant tree cutting and discarded plastic washed into rivers are another bane of the big cities, Chennai being no exception.
When the heaviest rainfall in over a century caused massive flooding across Tamil Nadu in 2015, driving thousands from their homes, shutting auto factories and paralysing the airport in capital Chennai, Reuters quoted PM Narendra Modi, as blaming “climate change for the deluge, injecting urgency into the debate at global climate talks in Paris and highlighting the vulnerability of tropical nations like India to extreme weather”.
Chennai, India’s fourth most populous city, is a major auto manufacturing and IT outsourcing hub with Ford Motor, Daimler, Hyundai and Nissan and US listed outsourcing firm Cognizant among some big names.
Media reports have highlighted how Cooum River, Adyar River and Buckingham Canal – serving as the main rain water drain for the city – have seen encroachments. The economic cost of the deluge cannot be overemphasised. In 2015, the Assocham put the financial loss due to record-breaking rainfall in Chennai and several parts of Tamil Nadu at Rs 15,000 crore.
Per capita greenhouse gas emission
Chennai being one of the cities where per capita greenhouse gas emission falls in the higher category, an Indian Institute of Technology – Madras (IIT-M) research concluded in June 2020 that rise in carbon emission may lead to extreme rainfall in Chennai, adding, the area affected is likely to expand.
‘Future is ominous’: Better urban planning strategies need of the hour
While global warming has destroyed the concept of the monsoon, as per Raghu Murtugudde, an atmospheric scientist at the University of Maryland, climate change isn’t the only culprit, says the New York Times. “Decades of greed and mismanagement are far more culpable. The lush forests that help to hold the rains continue to be cleared,” NYT reported in November 2019 while talking of India’s water woes. The future is ominous for India’s 1.3 billion people. “By 2050, the World Bank estimates, erratic rainfall, combined with rising temperatures, stand to “depress the living standards of nearly half the country’s population,” NYT added.
Smithsonianmag.com, while suggesting “better urban planning strategies to withstand disasters like flooding”, had a message for the southern Indian city: Chennai can take a page from another disaster-hit city: Guiuan, Philippines.
“The city, which sustained severe damage during Typhoon Haiyan, is embracing the reality of its storm-swept status and has decided to build a storm-resistant school complete with community emergency center,” Smithsonian Magazine website wrote in December 2015.