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    T X h

    UCRL- 83583PREPRINT0|0>V - ^ G l O ^ ' M

    NUMERICAL SIMULATION OF SELF-INDUCEDRATNOUT USING A DYNAMIC CONV ECTIVECLOUD MODEL

    Char l es R . Molenkamp

    FASTERThis paper w as p r epared fo r p r es en ta t ion a tVHI th In t e r na t io na l Co nfe ren ce on Cloud Phys icsCle rmont -Fer r and , F rance , 15 -19 Ju ly 1980

    March 1980

    rjISTWHTOON W THttOOOUUHmSUMUlMTED

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    N U M E R I C A L S I M U L A T IO N O F S E L F - I N D U C E D R A I N O U TU S IN G A D Y N A M I C C O N V E C T I V E C L O U D M O D EL

    C harles R . MolenkampL a w r e n c e L i v e r m o r e L a b o r a t or y , U n i v e r s i t y o f C a l i f o rn i aL i v e r m o r e , C a l i f o r n i a 9 4 5 5 0 , U . S . A .

    1 . I N T R O D U C T I O NF a l l o u t o f r a d i o a c t i v i t y f ro m t h e a t m o s p h e r i cdeton at ion o f a nuc lear w eapon can produce asev ere co l la ter a l damage hazard . This hp .zard canb e m i t i g a t e d b y d e t o n a t i n g t h e w e a p o n a s a f r e e - a i rburst , i . e . , far enough above the ground that thef irebal l doe s not conta ct the sur face . For a free-a irburst pr im ary dam age is in f l ic ted by b last andt h e r m a l e f f e c t s ; t h e r a d i o a c t i v e d e b r i s , w h i c h f o r m sa s s u b m i c r o n p a r t i c l e s , i s w i d e l y d i s p e r s e d b ya t m o s p h e r i c m o t i o n b e f o r e f a l l i n g t o t h e g r o u n d .I f pr ec ip i ta t io n i s fa l l ing in the v ic in i ty o f anuclear burst , the rad ioact iv e debr is pa rt ic les canbe entra ined by the c louds and rapid ly scavenged

    and dep os i t ed on the ground produc ing a s ever ec o l l a t e r a l d a m a g e h a z a r d. W e h a v e e x p e n d e dcons id erab le e f f or t a t LLL try ing to assess th ishazard looking a t microphys ica l , dynamic , andc l i m a t o l o g i c a l a s p e c t s , a nd h a v e c o n c l u d e d t h a t as ign if ican t haza rd w ould occur i f the debr ise n c o u n t e r s p r e c i p i t a t i o n b e f o r e i t i s d i s p e r s e d .B e c a u s e p r e c i p i t a t i o n s c a v e n g i n g c a n o c c u r o n l yw hen i t i s ra in ing , there i s an upp ir l im it on theprobabi l i ty o f natura l ra inout o f about 0 .2 .T h e p r o b a b i l i t y o f a r a in o u t c o l l a t e r a l d a m a g ehazard could be cons idera bly enha nced i f the c loudp r o d u c e d b y t h e n u c l e a r d e t o n a t i o n d e v e l o p sprec ip i ta t ion . We ca l l the phen ome non of rap iddepos i t ion o f nuc lear w eapons debr is by a c loud

    c a u s e d d i r e c t l y b y th e e x p l o s i o n s e l f - i n d u c e dr a i n o u t. S e v e r a l y e a r s ag o w e i n v e s t i g a t e d t h i sp o s s i b i l i t y u s i n g a d y n a m i c c o n v e c t i v e c l o u d m o d e lto s imu late th e l i fe cyc le o f a nuc lear c lo ud w iththe resu lt th at prec ip i ta t ion occu rred and as ign if icant a mou nt o f rad io act ive deb r is w asd e p o s i t e d . 2 On the bas is o f th is s imulat ion w esurvey ed the U .S . nuc lear tes t data for ev i den ce o fse l f - i ndu ced ra inout , but w e d id not f ind any . Thisw a s n o t p a r t i c u l a r l y s ur p r is i ng f o r t h e N e v a d a t e s t sbeca use o f the ar id c l im ate and the cr i t er io n toa v o i d p r e c i p i t a t i o n . F o r t h e P a c i f i c t e s t s , w h e r ese l f - ind uced ra inout w ould be more l i ke ly , theobserv ers w e re s i t uated 10 or more m ile s upw ind ofthe deto nat ion po int and w ould not have s eenpre c ip i ta t i on fa l l ing from the base o f the nuc learc l o u d i f i t o c c u r r e d .2 . O B S E R V A T I O N S A T H I RO S H IM A A N DN A G A S A K I

    A b o u t t h e t i m e w e c o m p l e t e d o u r s u r v e y o f t h etes t data) w e w er e to ld about the "b lack ra in" thata c c o m p a n i e d t h e n u c l e a r e v e n t s a t H i r o s h i m a a n dN ag asaki , Japan . "There has a lw ays be en con cernb y s u r v i v o r s w h o w e r e e x p o s e d t o t h e s o - c a l l e d"black rain' . . . The updraft ca use d by the nuc learexplos ions drew much debr is and dust in to thea t m o s p h e r e . T h e e n s ui n g t u r b u l e n c e g e n e r a t e d r a in

    show ers in both c i t ies beg inning about ha l f an hourafte r th e b las t . The f irs t ra in that fe l l w asdesc r ibe d as b lack , probably bec au se i t w ashed thedust and smoke from the burning c i t ies out o f theair. A numb er of survivors who had not bee n nearenough to the exp los ion to rec e iv e s ign if icant in i t ia lexposures w ere caught in the b lack ra in; theyr e p o r t e d r a d i a t i o n - in d u c i b l e s y m p t o m s . " ^ C o n cern abou t exposure to "b lack ra in" w as greatenough that one o f the i tems in the surv ivor reports ,w hich w ere compiled for thousands o f surv ivors ,d e a l t s p e c i f i c a l l y w i t h t h is p h e n o m e n o n .Evidence o f rad ioact iv i ty on the ground in thesuburbs o f Hirosh ima w as obta ined by the SecondJapanese Invest igat ion on 13-14 A ugust 1945 .

    "Samples found in the area 3 .5 km northw est o f theh y p o c e n t e r d e m o n s t r a t e d c o n s i d e r a b l y i n t e n s erad iat io n . This i s be l iev ed to be due to the fa l l o fb o m b f r a g m e n t s a s a r e s u l t o f m e t e o r o l o g i c a lcondit ions a t the t ime of the exp los ion ."* "A tt h a t t i m e [ 3 - 4 S e p t e m b e r 1 9 4 5 ] , in addition to them a x i m u m r e s i d u a l g a m m a r a y s a b o u t t w i c e a sin te ns i ve as the background in the v ic in i t y o f theh y p o c e n t e r , w e d e t e c t e d o n t h e S a n y o N a t i o n a lH i g h w a y b e t w e e n K o i an d K u s a t s u l > 3 k m w e s t o ft h e h y p o c e n t e r ] , g a m m a r a y s o f a b o u t t h e s a m einte ns i t y a s in the v ic in i ty o f th e hypocen tor , . . .The ca use o f th is rad iat ion i s cons ide red to bed if fe rent from that in the v ic in i ty a t the hypocenterand for the following reasons it is felt that uraniumnuclear f i s s ion products o f the A -bomb explos ionhad fa l l en . That i s , a t the t ime of the exp los ion , aneast w ind w as b low ing in th is area and there w asmuch ra in in th is area about 30 minutes a f ter theexp los io n . This ra in i s reported to have been b lackand d ir ty . Furtherm ore , ev id enc e that th is w as dueto fa l lout i s that espec ia l ly in tens ive rad iat ion w asfound in mud w hich had co l lec ted in an eaves troughof a house . . . C hemica l ana lys is w as conducted ona part o f i t (mud co l le c ted from ea ve s trough of asm al l hou se be low the U eno Garden w here theint ens i ty o f rad iat ion w as greate s t ) . . . and uraniumnuclear f i s s ion products w ere conf irmed to bep r e s e n t N 5

    "R a dioact iv i ty in the v ic in i ty o f N ish iyatnaR e s e r v o i r i n N a g a s a k i C i t y [ N i s h i y a m a R e s e r v o i r i s3 km eas t o f the hypo center ] w as measured andfound to be far greater than that o f the hypocentera r e a . . . I n t h e l a t t e r a r e a [ N i s h i y a m a ] , r a d i o act iv i ty w as found over a w ide area cover ing moret h a n 1 0 k m ' , . . . a t s o m e p l a c e s b e i n g a s h i gh asover 25 t i me s as s trong as that in the hypocenterarea [on 1 October 1 9 4 5 ] . Since N ish iyama areaw as dow nw ind from the hyp ocen ter a w ind of 3me ters per second w as b low ing then the ra inw hich fe l l about 20 minutes la ter must have w ashedd o w n r a d i o a c t i v e s u b s t a n c e s w i t h t h e d u s t b lo w n u pover N aga saki C ity . . . The v ic i n i ty o f N ish iyamabeing a h i l ly area , heavy ra ins w hich fe l l severa l

    D I S T R IB U T IO N B F T H I S D O C U M E N T IS U K L M I T E D

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    t i m e s f o ll o w i n g t h e A - b o m b d e t o n a t i o n b e f o r e t h em e a s u r e m e n t s w e r e s t a r t e d w a s h e d a w a y a l m o s t a l lt h e r a d i o a c t i v e s u b s t a n c e s on t h e r o a d . T h e r e f o r e ,g r a s s y a r e a s a l o n g t h e ro a d s i d e w e r e c h o s e n f o rm e a s u r e m e n t a n d s t r o n g r a d i o a c t i v i t y w a s u s u a l l yf ou n d i n s u c h p l a c e s . "Some of t he de t a i l s of t he "b l ack r a in" ar eg i v e n i n T h e R e p o r t o f t h e A t o m i c B o m b D a m a g e i nH i r o s h i m a . ' " 2 0 to ~ 3 0 m i n u t e s a f t e r t h e b l a s t ,

    t h e b l a c k c l o u d s n i m b o s t r a t u s m o v e d t o w a r d s t h en o r t h - n o r t h w e s t a n d it d i s t i n c t l y c a u s e d t o p r o d u c et h e p h e n o m e n a o f r a i n s h o w e r . T h e s h o w e r so c c u r r e d b e t w e e n t h e h o u r s of 0 9 0 0 - . 6 0P . . . F i r eb e c a m e w i d e s p r e a d f ro m a b o u t 0 90 0 > j u r s , w a s a ti t s he igh t be tw ee n 1000 and 1400 hou r s ands l ac ken ed in t he e ven ing . T hi s [mot ion of c loudsand smoke to th e N W ] s h ow s t h a t a s o u t h e a s t e r nwind was b low ing in t he upper r eg ion a t an a l t i t u der a n g i n g f ro m 5 0 0 t o s e v e r a l th o u s a n d m e t e r s . I t se s t i m a t e d v e l o c i t y i s 1 t o 3 m s e c - * . W e r e g r e ttha t we ar e unab le t o mak e a s tudy on a c tu a lo b s e r v a t i o n s a s w e d o n o t h a v e i n h a n d t h eo b s e r v a t i o n r e p o r t s o n t h e u p p e r a i r c u r r e n t s o f t h a td a y . [ A s f a r a s I c a n d e t e r m i n e , t h e y h a v e n e v e rb e e n f o u n d . ] T h e r a i n f a l l o n t h i s o c c a s i o n c a m e o ft w o - f o ld i n f l u e n c e s , o n e b e i n g t h e d i r e c t i n f l u e n c eof upward a i r cur r ent caused by the explos ion i t se l fa n d t h e o t h e r b e i n g t h e i n d i re c t i n f l u e n c e o f t h eu p w a r d a i r c u r r e n t c a u s e d b y t h e f i re a f t e r b o m b i n g .

    "The hour of i n i t i a l r a inf a l l r an ges f ro m 15min utes t o 4 ho ur s af t e r ob serva t ion of t h e f l ash ofthe explos ion , bu t in most p l ac es i t be ga n r a in ingf rom 20 min ute s t o an hour af t e r . . . Th e r a ins t o p p e d b e t w e e n 0 9 0 0 a n d 0 9 30 h o u r s a t t h e e a r l i e s tpoin t s and be tw ee n 1500 and 1600 hou r s a t t hel a t e s t . . . I t m a y b e co n c l u d e d t h a t t h e d u s t a n dsoot in t he a i t w ere for t he most par t w ashe d dow nto be l e f t on th e ground dur ing the f i r s t 1 t o 2 hour so f r a i n f a l l . . . I r e g r e t t h a t w e c a n n o t g i v e adef in i t e f i gure of t he am oun t of r a inf a l l i n t h ep r e s e n t c a s e a s t h e r e w a s n o t a s in g l e m e t e o r o l o g i c a l o b s e r v a t i o n u n i t e s t a b l i s h e d i n t h i s a r e a o fr a i n f a l l . B u t j u d g i n g fr o m t h e f a c t t h a t t h e r ea p p e a r e d a l m o s t t h e s a m e r i s e i n w a t e r l e v e l i n t h es a m e s h o r t h o u r s i n t h e m o u n t a i n s t r e a m s i n K o i a sw e l l a s i n t h e Y a s u R i v e r . . . a s on t h e o c c a s i o n o ft h e t y p h o o n e x p e r i e n c e d o n 17 a n d 1 8 S e p t e m b e r[ 1 9 4 5 ] ; i t i s e s t i m a t e d t h a t t h e r a i n f a l l i n t h e a r e aof downp our am ou nte d to 50-100 mm wi thin 1 t o 3hours of rain."

    "In N aga saki . . . , there was a showerphenomena far smaller in s c a l e a s compared wi ththat of Hiroshima. This is probably due to reasonsof the absence of frontier air current z o n e s a s w a ss e e n i n H i r o s h i m a a n d t h e fa r s m a l l e r s c a l e o f t h ef ire at the former c ity, w h i c h b e c a m e addi t ionalinf luential fac tors to the rain-forming condit i ons . " 7

    I sodose contours for Nagasaki as measured wi thGe iger counters by the U.S. Fir s t Technical Groupof the Manhatten Engineering Distr ict are shown inFig. 1 . These data were taken i 6 0 days af t er theev en ts and afte r 2 typhoons had swep t throu ghSouthern Japan, but they appear general ly cons i s t ent wi th the c r u d e J a p a n e s e m e as ur e m e nt sobt a i ne d pr e - t yphoon . A r a k a w a 8 e s t i m a t e s t h ee x t e r na l i n t e gr a t e d gam m a d o s e at about 100 rads inN i s h i yam a c om par e d t o s e v e r a l r a d s i n th e w e s t e r nsuburbs at Hiroshima.

    M y c o n c l u s i o n s a r e t h a t d e p o s i t i o n o fr a d i o a c t i v e d e b r i s b y p r e c i p i t a t i o n o c c u r r e d a t b o t hH i r o s h i m a a n d N a g a s a k i , a n d t h a t t h e p r e c i p i t a t i o nwas in i t i a t e d by the explos ion i t se l f a nd by thee n s u i n g f i r e s . A d d i t i o n a l m e t e o r o l o g i c a l d a t a a n df il m s of t h e s e d e t o n a t i o n s s u g g e s t t h a t p r e c i p i t a t i o nw o u ld n o t h a v e o c c u r r e d n a t u r a l l y . T h e d e p o s i t e dr a d i o a c t i v i t y w a s a s m a l l f r a c t i o n o f t h e d e b r i sp r o d u c e d b y t h e n u c l e a r d e t o n a t i o n , b u t t h e c o n t o u r s p r e s e n t e d a r e s u b j e c t t o c o n s i d e r a b l eu n c e r t a i n t y d u e t o q u e s t i o n s r e g a r d i n g t h e m i x o fr a d i o a c t i v e d e c a y p r o d u c t s a n d c h a n g i n g d e c a y r a t e sa n d b e c a u s e o f w e a t h e r i n g d u r i n g t h e t i m e b e t w e e nd e p o s i t i o n a n d m e a s u r e m e n t .3 . S I M U L A T I O N O F N A G A S A K I E V E N T

    D u r i n g ou r r a i n o u i r e s e a c h w e d e v e l o p e d at w o - d i m e n s i o n a l a x i s y m m e t r i c c o n v e c t i v e c l ou dm o d e l of p r e c i p i t a t i o n s c a v e n g i n g . T h e c lo u dd y n a m i c s a n d m i c r o p h y s i c s w e r e t a k e n f r o m t h eR a n d ' C u m u l u s D y n a m i c s M o d e l ." W e d e v e l o p e d ar e p r e s e n t a t i o n f o r s c av e n g i n g o f s u b - m i c r o n a e r o so l s for t h i s mo del t ha t is com pat ib l e wi th t heK e s s l e r m i c r o p h y s i c s p a r a m e t e r i z a t i o n . W e h a v eused th i s mode l t o s imu la t e t he scaven ging andd e p o s i t i o n o f r a d i o a c t i v e w e a p o n s d e b r i s b y n a t u r a lc o n v e c t i v e c l o u d s .S ince we had th i s model avai l ab l e , we used i t i na n a t t e m p t t o s i m u l a t e s e l f - i n d u c e d r a i n o u t . 'Thi s was done wi th t he r ea l i za t ion t ha t t h i s appl i ca t io n of t h e mod el v io l a t es one of t he bas i cd y n a m i c a s s u m p t i o n s , t h a t t h e d e n s i t y p e r t u r b a t i o no f t h e a t m o s p h e r e i s s m a l l . N e v e r t h e l e s s , t h es i m u l a t i o n p r o d u c e s a n a c c e p t a b l e s i m u l a t i o n o fnuc lear c loud r i se and i s cons id ered r ea sona blyr e a l i s t i c . 'T h e m a j o r d i f f e r e n c e b e t w e e n a s i m u l a t i o n o fs e l f - i n d u c e d r a i n o u t a n d n a t u r a l c o n v e c t i o n i s t h ei n i t i a l p e r t u r b a t i o n . F o r t h e s i m u l a t i o n o f t h eNag asak i eve nt , w e used a weapon s y i e ld of 22 kT,

    a n d e x t r a c t e d d a t a o n i n i t i a l t e m p e r a t u r e(3000C) and f i rebal l radius (230 m) f rom Ref .10 . W e f u r t h e r a s s u m e d t h is t h e r m a l e n e r g y ha d acos^ (R) d i s t r i bu t ion f rom a ma xim um at t hecen ter t o amb ien t a t a r ad ius of twi ce t he f i r ebal ls i z e . T h e r a d i o a c t i v i t y w a s a s s u m e d t o h a v e as i m i l a r d i s t r i b u t i o n .The s imula t ion was s t ar t ed f rom r es t wi th t h i sa s s u m e d per turbat ion an d run with an in i t ia l gr idspacing of 100 m from 0-30 sec . A t t h i s poin t t h egrid spacing was change d to 300 m and th e mo delres tar ted u s i n g t h e m o t i o n f i e l d , t e m p e r a t u r e a n dd e b r i s d i s t r i b u t i o n s a t 3 0 s e c . N o c o n d e n s a t i o n h a docc ur r ed a t t h i s t im e. W i th a 300 m gr id spacin g thedom ain of t he m ode l was he igh t 13 .5 km , r ad ius 9k m .Tht> dev elop me nt of t he c loud c l ear l y depen dson the vert ical s tructure of t h e a t m o s p h e r e . W ehave not bee n ab l e t o fi nd any upp er a i r da t a t akenin Jap an a t t h i s t ime , app aren t ly i t has beende s t ro ye d . W e d id f ind da t a f rom a ser i es ofw e a t h e r r e c o n n a i s s a n c e m i s s i o ns fl ow b y U S A F o v e rJ a p a n from G u a m . A s p l a n e s a p p r o a c h e d t h eJ a p a n e s e I s l a n d s f ro m t h e e a s t t h e y a s c e n d e d f ro mabo ut 2000 f t a l t i t ude to 30 ,000 f t and tookm e a s u r e m e n t s o f t e m p e r a t u r e a t 1 0 0 0 f t in t e r v a l s .Only one of t hese f l i gh t s r ecorded humidi ty da t a , af l ight on th e m orning of 9 Augu st ( t he day of

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    Nagasaki bombing) ; we used the sounding from thisflight in the s imulat ion for Nagasaki . S ince the dat aends at 30,000 ft, we placed the tropcpause at t ha tal t i tude al though it was probably ^uite a bit highersince there was a high pres sure region centered jus teas t of Japan at t h i s t i m e . In the s imulat ion thenuclear c loud rises to this tropopause in about 4minutes , af t er which the buoyancy t erm becomesne gat i ve and the upward ve loc i ty decreases . Thecloud is al so approaching the top boundary of themode l . In the s t r e am f unc t i on - vor t i c i t y f or m ul a t i on ,the upward ve loc i ty t ends to be deviated to radial lyoutward, but thi s is a minor e f f ec t in thi s par t i culars imulat ion.Sub-gr id mot ions are represented in our m o d e lby a Fickian di f fus ion t erm. We have used adi f fus ion coe f f i c i ent of 400 m' s e c - * , a ve r yhigh value even for convec t ive c louds but perhapsnot unreal ist ic for nuc lear weapons c louds par t i cularly at e ar l y t i m e s . The model results are fair lydependent upon the va l ue of thi s parameter .An axi - sym metr ic mode l cannot represent thehor i2ontal mot ion of the external atmosphere andparticularly wind shea r. Even a re lat ive ly smal lhorizontal wind shear can dramat ical ly af f ec t thedeve lopment of the c loud. Fi lms of the N agas ak ievent sugges t that the wind shear was smal l , but not

    ins ignif icant , and the distribution of de pos i t e dradioact ivity suggest downwind transport of thedebris at about 3 m s e e " * . We assumed in pl o t t i ngour s imulated depo s i t ion pat terns that the c l oudmoved as a whole wi th a ve loc i ty of 5 m s e e ~ l .The scavenging param eter izat ion en vi s ions atwo-s tep removal pro ces s . Sub-micron debr is par t i c l e s are as s um e d to become at tached to orincorporated in cloud droplets at a rate of 10~*s e c " 1 . These debris- lad en droplets can beinert ial ly captured by raindrops, which transport thedebris to the ground . Tota l evaporation of dr op l e t sand raindrops bef ore they reach the ground l eads toresuspension of r ad i oac t i v i t y in the at m os phe r e . Inthe s imulat ion there was no scavenging of debris bynuc leat ion or di r e c t a t t ac hm e nt to raindrops.Of the radioac t ivi ty entrained into the c loud inthe s imulat ion of the Nagasaki event only 14percent is captured by drople t s and only 3 p e r c e n t isdeposited on the ground by raindrops. Theremainder is l e f t suspended in the atmosphere af t erprecipitat ion stops and the cloud diss ipates .In the s imulat ion ini t ia l condensent lon occurs at^2 minutes af t er burs t , and rain starts fal l ing at 5minutes . The c loud base is 1.2 km and m axi m umcloud top is 13.Z km. Rain continues for 30 m i nut e *wi th maximum accumulat ion, as suming no c loudmot ion, of 8.5 mm. Maximum rain rate at c loudcenter of 31 m m / hr oc c ur s at IS minutes .The surface 'distr ibution pattern of de pos i t e dradioac t ivi ty , as suming a 5 m BBC"1 wind, is g i ve nin Fig. 2. This pat tern can be compared' with themeasured pat terns given in Fig. 1. We f ee l thesepat terns compare very favorably given the Uncer taint i e s in both the s imulat ion and the obs e r va t i ons .The greater downwind di splacement in thes imulat ion is due pr imar i ly to an ove r e s t i m at e ofthe mean wind.

    . DISCLAIMED 1 :TMiiboo. *.tDrepjiedotannaunt ot wot. looniotad bv n agar*, o( tb* Unted Slai n Government, iFtdther tne Unced 5lm Go.etnrenl nut any *cflt tnetedI. not an, ot net* eirCo.** !. tt uieian ymiranty. WT U a nr.lad. v atajmec any teoat t*Atl'ty u* tewantrtiiliiy l ot tbe ar oin ty,aynoteletteii, a uielulneu at any Intotmalktn. apoa*alm, otodutl. n. ccneitute or Imcly i t, (atdottamant, ritammtndetwei. w l iw in , bv tbe Un

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    FIGURE 1. Isodose contours evaluated in milliroentgens per hour for October 3 -7, 1945, at Nagasaki. Figurereproduced from Ref. 3.

    5 6 7 8Downwind distance (km)

    10 12

    FIGURE 2. Isodose contours calculated by the s caveng ing model for Nagasak i assuming 5 m se c" 1 wind.Contour levels are 500, 400, 300, ZOO, 100, 0 rad hr" 1 at H+1 hour. The maximum doBe rate is ^25times the comparable measured dose rate.9. Murray, F. W., 1970, "Numerical Models of aTropical Cumulus Cloud with Bilateral andAxial Symm etry," Mon. Wea. Rev., 98(1), 14-28.

    10. Glasstone, S. and P. J. Oolan, 1977, TheEffects of Nuclear Weapons, prepared andpublished by the U. S, Department of Defenseand the U. S. Department of Energy.KS:FLW/H34z

    NOTICEThb hcpatt was prepared as an account uf Work sponsored by the UnitedStates Government. Neither the United States nor the United StatesDepartment or En erg y nor any of their employ ees, not any of theircontractors, subcontractors, or their employees, makes any warranty,express or implied, ur assumes any legal liability or responsibility for theaccuracy, completen ess or usefulness of any Information, apparatus,product or process disclosed, or represents that its use would not Infringeprivately-owned rights.Reference to a company or product name does not imply approval orrecommendation of the product by the University uf California, or the U .S.Department of Energy to the exelua; n ofoih eis that may be suitable.

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