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<br />Rnch rjl~C1'C' cumplex ig given a tH\f.l\.U~
<br />ce.!.l 1c!entlflcat:~on nt!,,'bcr Wh.!.C~l rc:lIlains
<br />~sociated wit.h l;!h.: c\J"~P!.cx until it either
<br />-(!1!i:ji!1J~es or'mC:J:r,l..':) I!lto u ltlt'g~r complex.
<br />T1u::: c.a:l.!. ic!entif '.1.:'<\ [.'.t.l1\ number is used only
<br />once ~o avoid tm;' l;.1..1!1 fusion w.!..th ~Hlotllt::r
<br />com:,.!.~x whie!l mOJ:' t..'ll.:l.:t!r Ht a ;.tlter t!.m~. ^
<br />lIst of all th~ nr! :.!,In<ll 20 d!~z t:cho iden-
<br />tities which ar~ .a :)I,rt of n complex 1s gcn-
<br />crat.~J eac.h 5 ml'H,tl..'~. 't!le numtJ~r of ind tv!.c.!-
<br />ual 20 dBz echo~.i i.n each complex and tIlt:
<br />n~er of t!!erg~r::) or other compl~xe9 into the
<br />com?~cx arc a~so :!~~cJ. A r~corL is also
<br />kept. of which Co~~)::....xcs we.rta for!!ll;;':<! by
<br />sl'l!.tting from an\..lt1lcr one.
<br />
<br />After all of. the 5-minute radar com!)le.xe:$
<br />have !leen ce~en}j_llec. and nan\t~d. t~e file contain.::..n~
<br />the inc.!iv:!..cllJal I;1.':'t ::lummary recorc9 and. V01.U'Il~
<br />:U.l~.ry t'~corcs l~ n:--:,-!ln computt:r proces~t::c to a~..!
<br />tht:: volumo;.:s, C1rl~H:I, .md t'lllnfa.'.l estimates; comput:1t:
<br />a n~v ce!lt!"old; cc'~~rmine tht:: ''',-,x...!..mum dill. mal max-
<br />i~u!!! !;O~ va~ues i!n(~ .~oeations; Llnc:! compute the
<br />avcraz~ r~"infa"l.L rt~te. 1\ nl-.::w"fi.le 1'9 1>'t"o'C.U1.:ct! 'in
<br />t~e sa!!!e :ot'"'-at a~ :i"H(.~ividual 20 c!!z echo cacR
<br />fi~e ."!.:'!l n~w r.h~i\r C0T!1?~.ex identification numtters.
<br />litti:! ec~!o CU!llplc:< c'ulnlcteristic.:S~
<br />
<br />This E.i.1.e is then usee! Yith the ~ilme
<br />progra!!! t!la~ ge lCt'"H':cJ the l!.feti!!!e, maxinlu1n vo'!'-
<br />U~, an<! estiD!d!:~I~ :.utal rai1\ta~l for tll~ :!..Ilc.ivi~-
<br />ua.!. echoes ~o yLc,~\..~ ~;;.:.milar s~ati9tics for :.h~
<br />ra~ar co~?lexes.
<br />
<br />3.
<br />
<br />D!SC!:SS~O~
<br />
<br />Data were examined fro~ several days
<br />using separation ~L'.::itnnc~$ of 1.0, 1.5. 2.1), 2.5.
<br />and 3.0 ti!'tcs t:,c l..'o'.1l.vHlt::nt d1.lI''!t.!ter of tlll~
<br />larger echo. CUln~l: ...:xe::i formed ~JY t.hest:: sC'1arnti.o':l
<br />d!.stanct::::I 'Jere g.r.:.!u'l.i.cally d~p!.ctec as a t.t!"e
<br />se<!'..1E:nct:: of corr'~lo~i tt~ PPl pre~cntat1ons an(! CO~~)i.!!'"t::=c.
<br />w!.t~ ~!lOSt= cO~!Jlt::y.e:j tiu!)jectivc':y fornlec '1y a r~H.:...!.r
<br />..aM~Ys!:.. ..At:;. rnl~',~l':. ~le €:x[h:~cte<..~, no particll'.ar
<br />St::?ara,::.on ditil:~I'h:C 'Jniturnt~Y ug-reed wit~\ t'll.~
<br />ana:ys:'s juCg!'!~'II~. ':'1lt~ 2,0, ~.5, anc. 3.0 l~iHrnc:::::'!"
<br />s~!Htt'a':io!ls gC:'.cr,l.'..'Y uppeurcc L10St reasona1.,).:'..e.
<br />~~It:: 2.5 C':"2!::C!:t.r ~1'~).~!'ati0n n:)pe.ared to t!!t}SC
<br />CO!ls:.sten'.:~y C~II"')':fl.' '':~c 20 It\Z eC~lOe~ 3.1\':0 COIr:-
<br />!,~t::Y.t::s s~.'!l!..:ar ':0 ,:11O~~ of t\1e raear ani..l~Ys '.:.
<br />
<br />'!a~lt~ ~. cun tain~ a comparison 0 f the
<br />freq'Jency 0': :.nc.l.'1 i.(',.!uJ. 20 c3z t::choes and raGar
<br />co!!!p:exe$ o':Jt,1.~!1C0. '.t:iing th~ 2. 5 clamet~r ~H::,ura-
<br />t.!..on for bOt.~1 j!!!Y~. .~'ht:: frontal. day had t~\rt::e
<br />:.i!!'..c:l as !!'.any .!.nl:.~ v i,l~U~I1.. echoc~ as the aj nTt..I~S
<br />conVc-ct.!.on c!.lY. A!".:~r th~ 2.5 equivalent cC~lO
<br />dla~~ter ::;e~~l..,.~t:!l..\n Jctwcen !..l1d!.viduul C.c!1O~~ \l~::i
<br />use:d t:o for::! t,!.J!'l:l";CX~~.s. the frontal day !we un.:!.y
<br />61)Z !!!:ore coe:?..!..:~-:I.!~ :"!l~m th~ .i.'...L!."~li1SS day. ~~ot~\
<br />cays !l(!C ov~r: :'):~ 0 f c~\e tota:!.. !1u~jer of eC:10t:::l
<br />exist.:nt> cur.!.nl"' O!le r)ur'.:icu.~i.!r 5-!:l.inute ncr.~oi! '""!.':~
<br />a maxi~~!!!. of 65 ''1L~.:''~'ldu(Jl echot::s on the. fronca:
<br />day. !!ot~ ~ays lqll.~ 41 Eew comp~cxes that containc~
<br />most: of the !.!t~JvJ.(''...!<.l.l 20 dHz ~c:loes. Ov~r ha:f
<br />of ':.he co!!!olt::xe:.; ':or ~ot.h dHYS concainec. on.!.y o-ne
<br />20 c.!~z eC~lO.
<br />
<br />Althou!="I, ,"ost. of the complexes d!.d not.
<br />have other CO~i'~I.'xt.'s llI~rg,e Into chern, ~cvcral
<br />~t'gers d!..l OCCt\l~. ~!owcver, most of the !'J~rgers
<br />werc;: i.nto on.!.)' a few large cOf!1~:exes. On che
<br />
<br />ail:1!18~9 day over 50 percent of the totu:!. mergt:rB
<br />wel~n into only one oE t',~ complexes. Appcux:i.mOJle.ty
<br />ont~...fourth or the total nlt:rger9 on the fronta~ duy
<br />\J~'~t~ into only one compleX.
<br />
<br />Both daYl:i had a substantial port.ton of
<br />th,~ complexe~ form by splitting from other complexes.
<br />It "hould be noted t!,at the method of dd.lnJng CUIll-
<br />pl,e:<es did \lot prevt!nt an individual 20 ollz echo
<br />frJID splitting from a complex and 1UttH' lilt: rglng Lnto
<br />either the tHllne one it split from' or another CUnlP.tcx.
<br />1111s. obviously happened on t:he frontal day because
<br />the 8um of the ",,,rgers and splits is slightly .large<
<br />than the total nUll1b~r of complexes.
<br />
<br />Table 2 contains the echo or complex vol-
<br />ume. area at 1 d..:grc\": uutennu tllt angle, uuratJon,
<br />anI..! th~ rad'ur est: lmated rainfall for both the fronl:al
<br />mal ainnas~ coovect.lon dnys. \~lth the ~xc~{ltiol\ of
<br />tht:: rnlnfall, all of the parameters ar~ similur
<br />between the two. days. Even though there were three
<br />t!n~es as mallY 20 dtlz echoes on the f.rontal day
<br />('!'.l!Jle 1), the 20 dUz echoes anu cOIl1()lt:xes hurl
<br />ar-p roxil'1.i.1t.ely the si:.Ime size and duration distribu-
<br />tJl..m as' t.huse .on'.the 'a-:(:rma'S'S 'c.onve'c:.t-ion.cuy.. "~h(:
<br />fuc:t that the. duration ot the comp1cxt:::i on the
<br />rrcl!ltal day is l~~::i than that of the 20 d~3z echot:s
<br />i~1 sO!!lc!wh.ac unexpected~ This may result trom t:1~
<br />convention oE as::ilgning the id~ntlElt.:r of a COtTl[lJ.~x
<br />that SO!.it9 to thut portion containing the most
<br />lHt,!:!.viJual echoe::l rather than th~ one that has tbe
<br />:!..ar~~st echo volum~ ur area.
<br />
<br />there was approximately 30% more total
<br />ra:tnfall on the fronta 1. day thun on the airmass cay.
<br />!IIJ\oIi:ve.r. on the avcra!!.c. echoes and complexes on tht.:
<br />a!xmass cO~lVe.ctlon day producl;d uppt'1.Jxllll<.ltcly tW~l.:1::
<br />t!lI~ ntinEall with cOUlpaeilble vo1uUl~::I J ueeas at I
<br />cllt and durations.
<br />
<br />I,.
<br />
<br />IlliMARKS
<br />
<br />Radar data from che nonht!rn n:lgh Plains
<br />were usee to compare the indlv.tduu.!. t.!chocs grt:C:ttcr
<br />th.l:'.. ::S l!Sz for a Jay.on which d cold fr:ont passed
<br />t~1.("ou~h tlic area and a ,day On which the echoes wert!.
<br />:or!"~(! !:Jy airmuss convt.::ct:!.on OIt."..Y. '~hc number- uf
<br />ccltucs Oil tIle frontal day was su~stant.LaU.y larger
<br />than ~hc airmass ddY. The sizt:: anL! duration of ellt:
<br />t!chocs \Jas comparub.!.c on both cays J but on i:.he
<br />i.lvcL:aie radar estimatei.! rainfall p~r echo was
<br />g,r~atr.: r on the a.lrmass day.
<br />
<br />The problems and results of combining t!1e
<br />j,nl~!..vldual echot::s into radar complexes were aJ.30
<br />(:.LscU~:.l~d. Based Oil the limited dC:l tn sample, :'~H:
<br />c:ompl~xe::; obtalned usJ.t\g the 2.5 echo dlalllct~r
<br />~ie!)ar,I:H:iof\ appeacc:d to agree best T,JJ.th tlte subjec-
<br />U.Vc: t:'t::Sll~t::; of a radar analyst. However., more
<br />,!ac.:J. \/ill have to be examined befor~ deciding on
<br />an o!ljcctlve definition of a radar complex.
<br />
<br />~j "
<br />
<br />REFERENCES
<br />
<br />.\c::!(,.erman, B., C. Achtemeier. H. Appleman, S. Changnon,
<br />l"~' !!uff, C. ~!o'rgiln. P. Schickedanz. R. Semonin,
<br />1976: Des:lgn of the High Plains Experiment
<br />with'specific focus on Phase 2, s;lngl~ cloud
<br />experimentation. Final Report on llIPLEX D~5J.gn
<br />Project 'to Division of Atmospheric Hater l{~sour.ceB
<br />Nanagement, Bureau of Reclamation Concract
<br />14-06-0-7i97. pp 231.
<br />
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