Will the 2019 floods change the way we respond to extreme weather events?

Experts say climate change isn't always the culprit; exploitation, pollution and encroachment by humans play a larger role in making a disaster out of a manageable hazard

Pune-based engineer Tejas Patil has always welcomed the monsoon, whose light-to-moderate rains have provided much relief to his city after the harsh summer each year. Welcoming the showers is something the 30-year-old who works for a unicorn start-up has been doing one season after another. 

Not this year. This time, he was one of the thousands of Pune-ites who lost their vehicles to flash floods this September. Treasure Park, the housing complex of which he is a resident, lost as many as 400 cars and over 1,000 two-wheelers overnight. The loss of vehicles is a smaller tragedy. The larger one is about the 38 humans who perished in barely two to three spells of short-period rains in Pune, a city that usually receives no more than 60 cm of precipitation during the four-month season. This time, however, it recorded the second highest rainfall it has ever received in the rainy season, at about 120 cm in four months. 

And it wasn't just Pune. Similar scenes were also witnessed in Sangli city in Maharashtra, and several places in Madhya Pradesh and Uttarakhand. The floods in Bihar and Assam, which are common every year, are firmly etched in the memories of Indians as river floods in which the river expands each year due to melting ice. The ones in Pune and MP were flash floods, wherein the river bloats for a short period due to a variety of factors such as extreme rainfall event coupled with poor drainage systems. And few can forget the havoc that Kerala floods of August 2018 wreaked.

What made 2019 different

“Heavy rainfall is a hazard, and a robust disaster management design can prevent a hazard from becoming a calamity. While the former is beyond human control, the latter lies squarely in the control zone, and is key to averting catastrophes,” says P P Marathe, a retired army officer who served as the head of a state government department that trains officials in disaster management. 

The 2019 monsoon experience was nothing short of a disaster, which explains why it is etched in public memory. The visuals of cars getting swept away in storm water and of people struggling to keep their houses intact is how we tend to remember this year's rainfall. 

Apart from inundating cities, floods razed farm fields and villages with an unusual intensity this year, mostly in unusual places. The flash flooding visible in cities due to improper town planning, and the erratic and changing nature of the monsoon contribute to our overall perception about weather in particular, and climate in general.

The 2019 monsoon season which started with a 33 per cent deficit in rainfall at the end of June ended with 10 per cent excess rainfall by the end of September, the official endpoint of southwest monsoon (SWM) season. In addition to this, the withdrawal of SWM, which normally starts mid-September and takes 45 days, started on October 9 and ended within seven days this time. This was the second fastest withdrawal in recorded history.

This very phenomenon was characterised by an unprecedented rise in extreme rainfall events in the country. Data exclusively shared by the India Meteorological Department (IMD) with Business Standard shows that extreme rain events have doubled during the four years, that is from 2015 to 2019 (See chart). 

The rise in extreme events was the most in August, in line with what appeared in media reports. Nearly half the areas in India where rains are measured saw extremely heavy rains in August 2019, compared to only about a tenth of the areas receiving extreme rains in 2015. 

Most of these disastrous rains, thus, were concentrated in a few spells of rainfall (or a few rainy days). 

Looking beyond climate change

“The prevalence of light-to-moderate rains in India is reducing,” says Pulak Guhathakurta, a senior scientist at the IMD who heads the climate application centre at the 144-year old institution. 

“The rise in these extreme events can be attributed to climate change. And there are many areas which are receiving less rainfall, too. But the late and quick withdrawal of the monsoon cannot be attributed to climate change. This can be the case only if such a withdrawal persists for a considerable number of years, so much so that it becomes a norm,” he adds.

While extensive research has shown that extreme rainfall events are a part of the process of climate change, the same has not yet been proven about the early withdrawal of the SWM.

Guhathakurta explains that the late and swift withdrawal this year was due to various monsoon systems staying active in the seas and over the land for an extended period--such as a low pressure area developed in the Arabian sea, and extending to central India, which is a perfectly normal phenomenon-- not climate change. 

The change in the monsoon period (from beginning and end) over a longer time frame of multiple decades, however, could be a part of the bigger change in the monsoon schedule, which is currently under scrutiny at the IMD. 

While official monsoon period might get revised soon, the amount of rainfall (climatology) has already been revised downward by nearly 2 cm for the national average. 

The human hand

But erratic and heavy rains, or the original “hazards”, as Marathe put it, are just the beginning of the problem. 

Pune-based Water and river conservationist Vinod Bodhankar says there are three critical reasons for the disaster: exploitation, pollution and encroachment. 

“Exploitation of the forest where the river originates and runs its initial course deprives the forest of the ability to channelise over-the-surface and sub-surface water flows. Pollution across its course and in towns and cities further clogs man-made water channels such as storm water drains. Thirdly, encroachment on water bodies changes the structure of river altogether, reducing its capacity to hold large amounts of water,” says Bodhankar. 

This is where the confluence of heavy rains and improper town planning give rise to the kind of disaster that gets embedded in our memories. But 2019 reminded us, once again, that apart from the rise in heavy rain events, climatological changes such as long-term reduction/increase in the quantum of rainfall, and weak disaster mitigation systems in cities together contribute to converting a hazard into a disaster. 

Patil, who lost his cars and thanks his stars for not losing his life, would understand the gravity of this change. He got the electricity back after 15 days, cooking gas connection after 18 days, and was able to use his parking space after a month.

The bigger question is whether we will collectively be able to comprehend the prognosis and the impact of the changing monsoon patterns and respond to it, both at the macro and micro levels.