-3can be aeen that fossll fuels are estlnated to contrlbute flve b1l11oa tons of catbon per yea! to the atnosphere aDd that about half of thls 1s reabsorbed by the oceans or by the biosphere. The concluslon that fossll fuel coabustlon represents the sole source of lncreaental carbon dloxlde involves assr:olng not only that the contrlbutions fron the b1o_ sphere and flou che oceans are not changlng but also that these tlro soulces are coDtlnulng to absorb exactly the aame aEount as they are enlttlnS. The World Meteorologlcal Organizatlon recognlzed the Deed to valldate these assulrptlons, paltlcuiarly 1n vlew of the fact that the rate of earbon dloxlde Lncrlase less than ZZ ot tii- rale at lrh1ch the atnosphere 1s exchanglng ".pr.".rrt" carbon dloxlde lrlth the biosphere and the oceans. The blologlsts have been clalnlng that deforestatlon and assoclated blogenlc effects on the contln.it" ,.p.es"ot an lEportant lnput of carbou dloxlde to the atmosphere. Vuglaph s,,"'r,"112Es glE results f!o!_ recent papers by a nr.rnblr of biologlsts6on the conEribu_ -;i;;i;. rlon of rhe bio.phere to rhe grorrrh of Co2 1n rie atuospher" to the contrlburlon of fossll fuel coubusilon, esttoat;;l;;-thls rarlo are presented ln the flrst columr. rnthetr Apr1l igii,-ai"r"2 estlnated that the ratlo of the lrelght of carbon fron netot,nooa trrrl.Jto the erelght of carboo frou fosEil fuel burned ln thls nay have approaehed 1.0. rrre fouonrng """t"ry-i""-io;ii, *:l_1.-1:,"::,0:-1 :"!.the oor:.nJ cralued that increase 1n carbon dioxlde due to th! expani sion of folestly and agricuJ.ture nas at least half that due to il"" fo1r. In Augusr of 1977, rhe Natlonal Acadeey Scfeic.s f111lonUust lssued a report+ whlch attrlbuted the Greenhouse Effect toof foss11 coEbustlon and whlch recelved a considerable aoount of sensetlonal fuel publlclty. Thls has produced a rash of papers by rhe blol;;i;;;lo support thelr posltlon. In January of this year, IloodweliS-""J-.-lr:mber of other authors froo acadealc and oceanographic ccnters llshed a paper claiulng that the terrestrlal blomass appears to !ub_ be anet source of carbon dloxlde for the atnosphere whlch is po""itfygreater then that due to fossil fuel con-bustlon. the foliowln!1eek, Stulver6 publlshed resulrs r.".a-"po"-if57ii2-i"aro" whlch reported thet the net release of carbon dloxlde froa the blosphere 1n ihe ceutury prl0r to 1950 was tvice as great as that f!o; foss1l fuel coo_ bustlon. Even Lf 1t ls assumed thai the blospherLc release 1950, the contllbutlon of the blosphere up to the present tfr" "aopp.J-L ,o,ria stlll be 1.2 thar fron fossll fue1. t"tre iast four' arrlcles'ii"i-ipublished 1n Sclence. ra the present DoDrh, 1,fl.-:9.:.3.yere.atl w1J-son, pubushed an artlcle 1n Nature whlch sugportE the elaln ihat defolestatlon ha6 produced at least half as uuch carbon dloxlde in the atDosphere as can be attllbuted to foss1l fuel. Non, you ldlI reDeEbe! that eerller 1n this talk lt rras polnted out that 1f the lncrease ln catbon dl0xlde in the at'osphere ls arr" tofossil fuel conbustlon, about 502 of the CO2 belng released remalns ln the atoosphere and the rest 1s absorbed 1n llther the oceans or the co'tlnents. If thete have been substaDtlal releases of carbon dloxlde ln addltion to that whlch can be attllbuted to foss11 fuels, the natural

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