The unpredictable nature of southwest monsoon notwithstanding, Odisha has managed just about normal rainfall this year even as 12 States have recorded deficient rainfall. A surprising feature of the monsoon though has been a complete absence of depressions which occur regularly over Bay of Bengal and are largely responsible for seasonal showers.
Between June 1 and September 30, the State received 1,148 mm rain as against the normal of 1149.3 mm, the India Meteorological Department (IMD) said, announcing the formal end of the monsoon season.
While some unlikely districts received excess showers, at least six of them, mostly coastal districts, were left high and dry. Districts such as Balasore, Bhadrak, Jagatsinghpur, Jajpur, Kendrapara and Nuapada received deficient rainfall which is qualified by a shortfall of 19 per cent. Three major districts such as Balasore, Bhadrak and Kendrapara recorded over 30 per cent deficient rainfall though these districts mostly had a problem of deluge in the past.
On the other hand, some districts on the rain shadow regions have been blessed with excess rain.
Western districts like Sambalpur and Jharsuguda and southern district Malkangiri reported over 20 per cent excess rainfall this year. The rest recorded normal rainfall.
Though the State managed decent showers, it was surprisingly abandoned by the normal features of southwest monsoons. Not a single depression was formed over the Bay Of Bengal this year which took the experts by surprise.
In fact, most of the showers were triggered either by cyclonic circulations or low pressures off the Odisha coast. “Normally, the State witnesses at least three depressions over the Bay every year, but the last two years have been some kind of an aberration,” said Director, IMD, Odisha, Sarat Chandra Sahu. Last year, just one system turned into depression over the Bay of Bengal and that caused floods in Baitarani river. This year, not a single weather system turned into a depression, let alone a cyclonic storm, which is higher in intensity.
“If you look at the pattern, even the low pressures were feeble. Odisha coast did not see a strong system during the entire season,” Sahu said.
In fact, the strongest system is currently formed off Andhra Pradesh coast but it has had little impact on the State.
Most systems were cyclonic circulations and formed close to the land, thereby never got the impetus to intensify into stronger systems. Low pressures forming closer to the coast moved into the land and lost the intensity before fizzing out.