Effects of the Covid-19 pandemic on the oceans

A lockdown due to the novel coronavirus (COVID-19) resulting in the closure of largest industries in the world for a period of 2 months was enough to cause a drop of 7% of the anthropogonic carbon dioxide (CO₂) in the atmosphere. Besides, the atmosphere oceans play a key role to buffer the greenhouse effect. Herein, the resultant reduction in CO₂ emissions on the productivity of the global oceans are studied. Often chlorophyll-a (chl-a), particulate inorganic and organic carbon (PIC:POC), and sea surface temperature (SST), are used to indicate the productivity of oceans. Based on the satellite estimates, a drop in chl-a is observed in North Europe, South China and Southeast USA during the pandemic. The observed reduction in mean chl-a by around 5% in China may have occurred due to a drop of 123 tonnes of CO₂ emissions. A cooling response of 0.5°C in mean SST is observed over most of the coastal areas. A considerable drop in CO₂ emissions in the North Indian Ocean translates into a drop of mean SST in the region by 5%. All these suggest that maintaining global activities as sustainable as the pandemic period, can help to recover the oceans.