Bengal recorded the highest number of lightning strikes from cloud to ground per square kilometre in India in 2020, according to a recent report.

South Asia Lightning Report 2020, prepared by Earth Networks, says Bengal received 9,40,958 lightning strikes from cloud to ground last year — about 11 per square kilometre.

The entire Bengal delta, spanning across West Bengal and Bangladesh, has become a hotspot for lightning strikes, says the report prepared by the US-headquartered Earth Networks, which operates the world’s largest hyper-local weather network.

Bangladesh recorded the highest proportion of lightning strikes on ground — 37.1 per cent — in south Asia.

The lightning strikes that were counted comprised intra-cloud fireworks as well as cloud to ground bolts, which can cause fatality.

In India, Jharkhand comes second with 10 lightning strikes per square kilometre. Odisha, Chhattisgarh,Tamil Nadu and Andhra Pradesh recorded between four and eight strikes per square kilometre.

In the overall lightning strikes category, Bengal stands fifth with close to 3 million strikes. Tamil Nadu tops the list with close to 6 million strikes.

Earth Networks developed the data based on their extensive network that constantly monitors lightning strikes through thousands of sensors.

“For all of 2020, Earth Networks… detected 39,549,444 lightning pulses in India, of which 12,022,402 were dangerous cloud-to-ground strikes…. Lightning (strikes) increased by 22.6 per cent (in 2020) compared to 2019,” the report states.

The rise is even more striking if one considers the period from April 2020 to March 2021.

“During the period, 18.5 million lightning strikes were recorded in India, which was a 34 per cent rise from the 13.8 million strikes between April 2019 and March 2020,” reads an analysis of a report prepared by the ministry of earth sciences, India Meteorological Department and Indian Institute of Tropical Meteorology (IITM), among other agencies.

The analysis was done by the Delhi-based environment think tank Center for Science and Environment.

The IMD report points out that the number of lightning strikes has doubled in Bengal during the period from April 2020 to March 2021, compared with the same period the year before.

“It’s a fact that the number of lightning strikes has increased in our state recently. Though many had succumbed to lightning attacks, the number is much less compared to many states despite Bengal receiving more lightning pulses,” said state disaster management minister Javed Ahmed Khan.

The IMD report says that 37 people were killed in the state, and 1,700 across the country, by lightning strikes between April 2020 and March 2021.

“Climate change, particularly warming, is contributing considerably to the rise of lightning strikes by enhancing heat and moisture, which are key components for lightning,” said Sunil D. Pawar, an expert in atmospheric electricity at the IITM.

“Heat waves cater to more thunderstorms, which in turn trigger more lightning strikes,” said K.J. Ramesh, a former director general of the IMD.