Did COVID-19 Lockdown Brew “Amphan” into a Super Cyclone?

Abstract

<jats:p>The world witnessed one of the largest lockdowns in the history of mankind ever, spread over months in an attempt to contain the contact spreading of the novel coronavirus induced COVID-19. As billions around the world stood witness to the staggered lockdown measures, a storm brewed up in the urns of the rather hot Bay of Bengal (BoB) in the Indian Ocean realm. When Thailand proposed the name &amp;ldquo;Amphan&amp;rdquo; (pronounced as &amp;ldquo;Um-pun&amp;rdquo; meaning &amp;lsquo;the sky&amp;rsquo;), way back in 2004, little did they realize that it was the christening of the 1st super cyclone (Category-5 hurricane) of the century in this region and the strongest on the globe this year. At the peak, Amphan clocked wind speeds of 168 mph (Joint Typhoon Warning Center) with the pressure drop to 925 h.Pa. What started as a depression in the southeast BoB at 00 UTC on 16th May 2020 developed into a Super Cyclone in less than 48 hours and finally made landfall in the evening hours of 20th May 2020 through the Sundarbans between West Bengal and Bangladesh. Did the impact of the COVID-19 induced lockdown drive an otherwise typical pre-monsoon tropical depression into a super cyclone?</jats:p>

Livelihood challenges of ‘double strike’ disasters: Evidence from rural communities of southwest coastal Bangladesh during the Covid-19 pandemic and cyclone Amphan

“…55 days into Bangladesh's lockdown, Cyclone Amphan struck Bangladesh and India, at around 4 pm local time on May 20th 2020. Developing rapidly from a depression to a super cyclonic storm within 24 h, it was designated as the first ‘super-cyclone’ (category 5 tropical storm) of the century to arise in the Bay of Bengal ( Vinoj and Swain, 2020 ). Per government estimates, Amphan incurred a death toll of 129, and caused US$13.7 billion and US$130 million in damages in India and Bangladesh, respectively, making it the costliest storm recorded in the North Indian Ocean ( Sud and Rajaram, 2020 ; GoB and UN, 2021 ).…”

Abrupt emission reduction during COVID-19 intensified the spring 2020 rainfall over India

“…The dynamic changes induced by the reduction in anthropogenic emissions have produced an anomalous cyclonic circulation over the Bay of Bengal region. In a different context, Vinoj and Swain (2020), observed enhancement of the atmospheric circulation related to a cyclone during the COVID-19 lockdown's low emission phase. Our model simulations show that significant surface heating as a response to emission reduction resulted in an anomalous low-pressure zone over the Indian region with two high-pressure zones to India's east and west sides (Supplementary Figure S3c).…”

Did the Countrywide Lockdown act like a catalyst in turning a cyclone into a Super-cyclone AMPHAN?

“…Therefore, the atmosphere over the BoB was rendered relatively clean due to the substantial decline in the anthropogenic activities and consequent lowering of aerosol loading by˜30% while an increment of seasurface temperature by˜1-2 ºC as compared to the preceding year (Vinoj & Swain, 2020). The decline in the concentrations of both aerosols and the clouds combined effectively increased the sea-surface temperature which compounded the warming of oceans due to global warming.…”

“…The decline in the concentrations of both aerosols and the clouds combined effectively increased the sea-surface temperature which compounded the warming of oceans due to global warming. The conditions like pre-existing high summer SST, climate change enhanced Ocean Heat Content (OHC) and lockdown induced decline in aerosols & clouds perfectly blended for the potential subsequent intensification of the cyclonic activity (Vinoj & Swain, 2020).…”