Southwest Monsoon Outlook, Global Warming or Sheer Coincidence? – India.com
New Delhi: The southwest monsoon is an essential weather system that provides India with rain from the month of June until September. Its significance is further amplified when we consider the fact that most of India rarely receives rainfall during the course of the rest of the year, which means that a deficient monsoon season has monumental consequences for India’s agricultural sector.Also Read – Climate Change Alert! Why Nepal Is Deliberating To Shift Base Camp Of Mount Everest
The years 2013 and 2015 are prime examples of times when a deficient monsoon resulted in damages to crops worth millions of dollars and led to suicides by thousands of indebted farmers, who had suffered massive financial losses due to crop failures. Also Read – From Mediterranean To North Sea: Europe Wilts Under Early Heatwave
However, Maharashtra, and indeed a significant chunk of India, has received “above average” levels of rainfall for 3 consecutive monsoon seasons, with each season witnessing a significant surplus in comparison to the norm otherwise. Also Read – Delhi Likely To Witness Thundershowers and Gusty Winds Today
This phenomenon arouses curiosity. Is this sheer coincidence that due to the conditions being favorable for normal or excess monsoon systems to form for 3 years in succession? Or is it due to a much graver problem, one that has to do with the warming of the seas?
A prime subject worth studying in order to answer this question is Mumbai, which receives a yearly cumulative average of 2205.8 mm of rainfall. For the past 3 years in succession, Mumbai has breached its cumulative average by a sizable margin, with a delayed 2019 season giving Mumbai 3163.65 mm of rain, 2020 providing more than a 50% surplus with 3686 mm of rain, and 2021 breaching the 3000 mm mark.
While all three years provided residents with pleasant and damp weather, it also posed a worrying question and seemed like a foreboding warning of what the future has in store for the Indian monsoon system.
The Indian Meteorological Department (IMD) explained the surplus rain in 2019 attributing it to the presence of offshore troughs that remained active for a period that was longer than the norm, alongside the tendency of low-pressure systems in the Bay of Bengal to form rapidly.
However, it’s important to note that the monthly averages for rainfall in all three years (2019, 2020, and 2021) were achieved in a matter of just a few days of incessant rainfall. The IMD states that this is a worrying indication of extreme weather events driven by warming seas and climate change, as the days which received heavy rainfall in all three years often led to dangerous flooding, landslides, and incidents of tree fallings.
As a matter of fact, nearly 4000 trees fall in Mumbai every year due to incessant rain during monsoon which has led to many injuries and casualties.
An example of an unusually strong and destructive weather system that impacted Mumbai’s southern coast was the downpour that occurred on 4 August 2020. Mumbai’s southern suburbs, such as Colaba and Malabar Hill, rarely encounter flooding that chokes arterial roads due to the nature of monsoon rains impacting the greener, hillier northern suburbs to a much greater extent.
The disparity between the amount of rain that Colaba receives in comparison to Santacruz is so stark that on September 5, 2019, Santacruz received nearly thrice as much rain as Colaba at 217 mm, against Colaba’s 71mm. However, the southern parts of Mumbai received nearly 250 mm of rain on August 4, 2020, in a span of just a few hours, causing a landslide in the posh Kemps Corner locality. What was worrying though, was that Santacruz received a fraction of this rain, and it is a matter of concern that such powerful storm systems have begun to affect areas that previously were unaffected.
However, the biggest warning sign that we can consider when answering the question about the changing monsoon patterns is the cyclones that hit Mumbai in 2020 and 2021.
Mumbai is a city that is rarely affected by cyclonic activity. It experiences days of extremely heavy rainfall, such as those seen in 2005 and 2020, but none of them are caused by cyclonic activity. In fact, prior to 2020, the only instance of a cyclone hitting Mumbai took place in 1891! So, when Mumbai was pounded by cyclones for 2 years in succession, it served as a stark reminder of the effects of climate change in India, as the two cyclones wreaked havoc across the west coast, somewhere where it was not meant to strike.
So, what’s the monsoon outlook for this year? Well, the IMD predicts a normal monsoon for India, wherein there would be between 96% to 104% of the Long Period Average throughout the country. A normal monsoon season should be driven by the La Niña phenomenon, which is a weather phenomenon that positively affects the Indian Monsoon season.
There are high hopes for this monsoon season as it clashes with times of record inflation. A good monsoon boosts crop production, which in turn helps in economic stimulation. It just goes to show the importance of a simple weather system, and the power it yields over the workings of the Indian Subcontinent.
– By Shaurya Sharma