A tornado over Orissa m April 1978metnet.imd.gov.in/mausamdocs/533214.pdf · the hail of diameter...

Post on 12-Mar-2021

1 views 0 download

Transcript of A tornado over Orissa m April 1978metnet.imd.gov.in/mausamdocs/533214.pdf · the hail of diameter...

l

Mausam, (1982), 33, 2, 235-240

551.515.3(541.5) " 1978"

A tornado over Orissa m April 1978

ASHlM K. GHO SHMeteorological Centre, Patna

(Received 8 October 1980)

lIT': - I . ~ I 9 78 .a~~ <:R'IlR ""~ f;rofj.;; om. '"'" ij~ ......-.: ""~""" """'" fio'IT "'" ~ I~ .m: ii ..ro """ ij <l"lfir .am.. of <it<: om...r-'i "" :u;m'i .a..,;r lJt I ~ '"" ~ ij m m .. """:~~ qf<F.... Fd.,l ""~ fio'IT "'" ~ I

ABSTRACf. An analytical study of a tornado which struck parts of districts Keonjhnr andCuttack in Orissa on 16 April 1978, causing large scale devastations of property and loss of humanand animal lives, has been made. Synoptic situation responsible for its formation have been d iscussed.

1. Intrcductlou

11 was 1630 1ST on 16 April 1978 when atornado struck the village of Purunabandhagudain district Keonjbar, Orissa and wiped it outcompletely. All together eleven villages in thedislriets of Keonjhar and Cutlack sufTered lossesdue to Ihe impact of the storm covering an areaof about 50 sq. km and having a population of6000. According 10 the Slate Government about90 per cent inhabit ants in seven villages in Ghasi­pura block of Anandpur sub-division of Keonjhardistrict and four villages in Dangadi and Kora iblocks of Jaipur sub-divi sion of ~utlack di~trictwere affected. 11 is stated that Ill-fated villageof Purunabandhaguda suffered losses of 141human lives and 231 heads of cattle (Figs. 1 & 2).

OD record there is only ODe othe r tronad owhich occurred in Orissa OD 12 May 1976(Gupta and Ghosh 1978) in which seven yillagesin Balasore district were affected. Th IS, alsocaused loss of human and animal lives anddamage to property.

1.1. General description

path, it destroyed everything, shattering houses,slashing and uprooting trees and sucking lipcattle or whatever came on its way, The waterof a pond in the village Purunabandhaguda wasSlicked out and fishes and mud thrown out. Thedebris was thrown to the north east corner of thevillage. The branches nf trees were found to betwisted at a height of 6 to 8 feet and those tha twere uprooted fell in Ihe modal direction of eastto south. The wind speed has been estimated tobe 150 to 200 kmph and duration 16 to 17minutes.

A newspaper report relates weird and fearfulitories. A ten month s old baby was suddenlylifled up some 20 feet into air as though bydiabolical hand and propelled forward some 30yards and then suddenly and mysteriously gentlyput down on a thick hcep of straw so that shedid not get a scratch on her body. A 25 yea r oldwoman was also lifted up from the same spotand at the same time, taken some distance anddashed violently against a tree so that she lostan eye. A man of the same place had fist sizehail hit his waist with a stunning blow. Whilehe sat down in pain he saw another hail hit hishullock and break its neck.

W= updraft velocity requ ired to supportthe hail of diameter d.

From the size of the hail as described above arough estimate can be made about the probableupdraft by using the equa tion (Wichmann 1951).

W ~ [ 2 PI dg l!3 p, k

According to the accounts o~ the eye wit­nesses, prior to the tornado, a big ball shape~dark cloud with luminous red hand around Itsuddenly appe ared in the sky in the northwestdirection. Th is was followed by dark~es.s an~ ..terrific sound of thunder bolt and of whirling .,,:,ndtha t churned the area. Funnel cloud was visibleand the tornado moved from northwest to sout!,- where,east for a distance of about 16 to 17 km. On It.

(235)