Chennai – The Greatest Proof That Climate Change is Real

Puzhal – one of Chennai’s primary water sources dried up within a span of one year due to monsoon failure. Image source – NASA Earth Observatory.

The city in the last two decades has undergone the kind of weather extremes that it did not see in the last one and a half century; climate change cannot be a phenomenon limited to the melting of ice-caps in Antarctica. It is happening right here, right now.

By Kinjal Pandey

Chennai’s landscape has changed rapidly over the last few decades. However, urbanisation is not the culprit to the water crisis. Unnatural weather patterns have are a after-effect of climate change.
Image credits – Unsplash (Karl Janisse)

Most residents of Chennai believe that the water scarcity issue in the city is a public policy failure problem, that increased demand of water and industrialisation has led to water shortage. While these factors cannot be discounted, here we attempt to look at historical data to see how Chennai‚Äôs natural wealth of the north-east monsoon and water bodies has changed over the last few decades and even the last century. 

Listen to the average rainfall in Tamil Nadu since 1901 till 2017 in a small piano audio clip. Patterned droughts and floods can be noticed by looking for a difference in notes.
Created using twotone.

The first giveaway that industrialisation may have borne a heavy cost on Chennai by polluting and changing the ecology of the area and not alone by virtue of taxing the water supply is simple. 

A Hundred Year Record Broken 

A hundred year plus examination of annual rainfall in the state of Tamil Nadu, provided by the India Meteorological Department, shows that rainfall in the state dipped below 500 mm annually since 1901, only three times, all three in the last two decades.

This happened first in 2001 (483.4 mm), 2002 (318 mm), 2003 (318 mm), and 2016 (535 mm) which is more or less 500 mm. This unnatural dip in annual rainfall implies that the natural rain patterns of the area, which despite witnessing massive changes never touched the kind of deficit that has been seen recently. 

Blue signifies the average rainfall in mm each year of the 21st century, from 2001 till 2011; the orange does the same for the 20th century (please note – numerals 1,2,3 etc. denote the last digit of the year).
One can clearly see that rainfall levels have drastically fallen in the 21st century.

The 2016 annual rainfall was only a tad better than the the lowest rainfall recorded in the state in 1876, when the Great Famine took place due to one of the worst droughts recorded in the history of the Deccan Plateau. 

Change in water occurrence since 1984 to 2019 near Chembarambakkam Lake. The dried up areas in red are small water bodies that have dried up; the ones in green have not.

That is not enough, historical reservoirs of the state, especially of the capital, Chennai have quickly begun drying up. Chennai district primarily relies upon Chembakkam Lake, Poondi reservior, and the Puzhal Lake as its freshwater source, all three of which depend upon rainfall. Due to erratic rainfalls in the part two decades, the bodies have begun to dry up affecting the water supply of the city. 

Short rain spell is not Chennai’s only problem

Unnatural activities like cyclones have made life for residents increasingly difficult.

via GIPHY

Cyclone Vardah in 2016 was very severe and stuck large part of South India including Tamil Nadu and Chennai suburbs. GIF credits – Times of India

In 2016 alone, Tamil Nadu was affected by four cyclones. These formations affect rainfall, prevent fishermen from going into the ocean, and in worse cases cause massive damage to life and property.

CyclonePressure YearWinds
Thane9722011140
Nilam992201285
Madi9862013120
Roanu983201685
Kyant997201685
Nada1000201675
Vardah9822016130
Ockhi9752017155
Gaja9952018128
Cyclone Vardah, a cyclone that killed 14 people in the first week itself.
Image credits – NASA Earth Observatory

While the city has been resilient enough to recover from everything that nature has thrown its way, this resilience is fast wearing off. Residents are either recovering from excessive heat, excessive rainfall, or acute water shortage at all times of the year. Productivity and quality of life are affected by these challenges that do not seem to go away. Today, it’s a matter of comfort but tomorrow Chennai’s very existence could be at risk as sea water levels continue to rise. Climate change deniers can study the change in Chennai’s weather pattern alone to know that the problem is very real.

Sources and tools

https://earthobservatory.nasa.gov/images/145242/water-shortages-in-india

https://app.twotone.io

https://global-surface-water.appspot.com/#features

https://unsplash.com/s/photos/chennai

https://www.ripublication.com/ijaer17/ijaerv12n22_146.pdf