Desarrollo de la Antártica

INSTITUTO BRASILEIRO DE ESTUDOS ANTARTIICOS: SCIENTIFIC ACTIVITIES ON ANTARCTIC Aristides Pinto-Coelho Director of Science and Technology Instituto Brasilelio de Estudos Amártidos Our first impress¡'ons on possible large Antarctic influences on Bra– zil's environment came with the earlíest studies on artificial radioac– tive contaminatíon (Sr-90) on Brazilían biologícal materíals (1958) (1, 2) : At that time, researches all over ~he world showed that the non uniform global atmospheric circulation of A bombs debris and its gradual precipitatíon (fa11 out) is depending of local factors (hemís– phere, latitude, water precipitatíon, etc.) and of the bomb's potency (fission, fusíon) . A curve presented by Alexander, Líbby and others (3) emphasízed those facts and ca1led attention for the near polar tropospheric injections (from stral",')sphere) of the fall out products. Such were the explanations found for the 1000v Brazilian soil conta– minatíon and, consequently, the low incorporation of Sr·90 by Bra– zilian biological materials (4). Later studies on global environmental pollution has shown how Brazil is well protected by natura) barriers against international pol– lution. The principal factors related 10 the Brazilian geographical protection are (5): l. More than 90% of the Brazilian territory is situated on the less populous and the less contaminated hemisphere. 2. Several natural barriers protect the country against internatio– nal pollution: the Atlantic Ocean (East, Northeas, Southeast). tl¡e mountains Parima-Guiano and the Amazon forest (North), and the Andean Cordillera West) . 3. rrhe country's principal population concentrations are scattered along or near the coast (the s!harpn~s of this phenomenon is decrea– sing with the general growth of Brasilia and its surroundings) . 4. The pollution problems in rile country. tJhough increasíng in some areas. are of local origins and do not affect seriously its popu– latíon. In regard to international poUution Brazil has its weak spot Achil. les heel Antarctica. Free pollutants, or assocÍations or derivatives of pollutants, expelled 10 the northern hemisphere's atmosphere, such as carbon monoxide (6), sulfurous oxide. ozone, spray additives and