1960\u2019l\u0131 y\u0131llarda buzdolaplar\u0131ndan yang\u0131n s\u00f6nd\u00fcrme makinelerine kadar her alanda kullan\u0131lan aletlerin etkisini artt\u0131racak bir organik bile\u015fik ke\u015ffedilmi\u015fti. \u00dcstelik maddenin do\u011faya bilinen hi\u00e7bir zarar\u0131 yoktu. Bu efsane bile\u015fen toplulu\u011funun ismi CFC idi. CFC\u2019ler k\u0131sa s\u00fcrede pop\u00fcler oldu. S\u0131kt\u0131\u011f\u0131m\u0131z deodorantlar\u0131n, sinek ila\u00e7lar\u0131n\u0131n, hatta sa\u00e7 spreylerinin bile i\u00e7ine girmeye ba\u015flam\u0131\u015ft\u0131 1980\u2019lere geldi\u011fimizde.<\/p>\n
Bir g\u00fcn kutuplarda ara\u015ft\u0131rma yapan bir grup fizik\u00e7i buzullarda garip \u015fekillere rastlad\u0131. Antarktika buzullar\u0131nda kare kare \u00e7at\u0131rdamalar g\u00f6z\u00fckmekteydi. Biliminsanlar\u0131 \u015fok oldular. B\u00f6yle kal\u0131n \u00e7izgileri yaln\u0131zca ultraviyole (uv) \u0131\u015f\u0131nlar\u0131 yapabilirdi. Ama bu kadar \u00e7ok ultraviyole \u0131\u015f\u0131n\u0131n ozon tabakas\u0131ndan ge\u00e7ebilmesi m\u00fcmk\u00fcn de\u011fildi! \u00dcstelik bu yaln\u0131zca g\u00f6r\u00fcnen etkiydi. E\u011fer kutuplara ultraviyole \u0131\u015f\u0131nlar girmi\u015fse, neden D\u00fcnya\u2019n\u0131n di\u011fer yerlerine girmemi\u015f olsun ki? D\u00fcnyal\u0131lar kitlesel bir cilt kanseri tehdidi alt\u0131ndayd\u0131lar. Peki, buna sebep olan etki neydi?<\/p>\n
Ara\u015ft\u0131rmac\u0131lar\u0131n, buna etki eden bile\u015fenin CFC oldu\u011funu ke\u015ffetmeleri \u00e7ok uzun s\u00fcrmedi. CFC ad\u0131 verilen organik molek\u00fcller bir sa\u00e7 spreyinden ya da deodoranttan \u00e7\u0131kt\u0131ktan sonra bir s\u00fcre s\u0131k\u0131lan yerde hi\u00e7bir bozunmaya u\u011framadan kal\u0131yor, bir \u015fekilde a\u00e7\u0131k alana \u00e7\u0131kabilmi\u015fse yo\u011funluk fark\u0131ndan y\u00fckselmeye ba\u015fl\u0131yordu. Sonras\u0131nda ise CFC molek\u00fcl\u00fcndeki klor (Cl) ultraviyole \u0131\u015f\u0131nlar\u0131n\u0131n etkisiyle ana molek\u00fclden kopup ozon tabakas\u0131n\u0131 yaratan\u00a0molek\u00fcllerinden oksijen \u00e7al\u0131yor, dolay\u0131s\u0131yla da ozon tabakas\u0131n\u0131 par\u00e7al\u0131yordu. \u0130nsano\u011flu, kendi kendini yok etmekteydi.<\/p>\n
Tepkime s\u00fcreci<\/p>\n
I) Cl+\u2192ClO+<\/p>\n
II) ClO+O\u2192Cl+<\/p>\n
Genel tepkime<\/p>\n
+O\u21922<\/p>\n
Duyulduktan sonra CFC sayesinde k\u00e2r etmi\u015f \u015firket, baz\u0131 sahtek\u00e2r biliminsanlar\u0131n\u0131 meydana \u00e7\u0131kard\u0131. K\u0131sa s\u00fcreli k\u00e2r\u0131 insan hayat\u0131na tercih eden \u015firketler, \u201cCFC kullanmazsak iflas ederiz, ekonomi \u00e7\u00f6ker\u201d diyorlard\u0131. Ancak kan\u0131tlar reddedilemez \u00f6l\u00e7\u00fcdeydi. 1984\u2019e gelindi\u011finde 20 y\u0131ld\u0131r atmosfere g\u00f6nderdi\u011fimiz CFC\u2019lerin ozon tabakas\u0131n\u0131 par\u00e7alamas\u0131n\u0131n g\u00f6zle g\u00f6r\u00fcl\u00fcr etkileri ya\u015fanmaya ba\u015flad\u0131. Ciltte yanma \u015fik\u00e2yetiyle hastaneye giden insanlar t\u00fcm d\u00fcnyada artt\u0131k\u00e7a Birle\u015fmi\u015f Milletler \u00fczerindeki bask\u0131 da artt\u0131. Art\u0131k ad\u0131m at\u0131lma zaman\u0131yd\u0131.<\/p>\n
Takvimler 22 Mart 1985\u2019i g\u00f6sterdi\u011finde Viyana\u2019da \u201cOzon Tabakas\u0131n\u0131 Kurtarma Konferans\u0131\u201d yap\u0131ld\u0131. Konferansa \u00f6zellikle CFC\u2019li aletleri \u00fcreten ABD, Birle\u015fik Krall\u0131k ve \u00c7in gibi sanayile\u015fmi\u015f devletler davet edildi. Durumun ciddiyetinin fark\u0131na varan otoriteler, 5 y\u0131l i\u00e7erisinde kademeli olarak CFC kullan\u0131m\u0131na son vereceklerini ilan ettiler.<\/p>\n
CFC t\u00fcketimi dursa bile, 2000\u2019li y\u0131llara geldi\u011fimizde, ozon tabakas\u0131 h\u00e2l\u00e2 gitgide inceliyordu. \u00d6yle ki \u00f6\u011flen saatlerinde baz\u0131 yerlerde d\u0131\u015far\u0131 \u00e7\u0131kamaz hale gelmi\u015ftik.<\/p>\n
2005\u2019ten sonra ald\u0131\u011f\u0131m\u0131z raporlar CFC \u00fcretiminin durdurulmas\u0131nda ne kadar hakl\u0131 oldu\u011fumuzu g\u00f6sterdi. Ozon tabakas\u0131ndaki incelme azalmaya ba\u015flam\u0131\u015ft\u0131. Ancak yine de tehlike devam ediyordu. T\u00fcm bunlardan sonra Eyl\u00fcl ay\u0131nda Birle\u015fmi\u015f Milletler\u2019in raporlar\u0131 adeta y\u00fcre\u011fimize su serpti. Elde edilen verilere g\u00f6re 30 y\u0131ldan sonra ozon tabakas\u0131n\u0131n incelmesini durdurmay\u0131 ba\u015fard\u0131k. 1960-90 y\u0131llar\u0131 aras\u0131ndaki tahribat\u0131m\u0131z\u0131 durdurmak bile 20 y\u0131l ald\u0131.<\/p>\n
Her ne kadar insanl\u0131\u011f\u0131 yok etme imk\u00e2n\u0131 olan bir tehlikeyi saf d\u0131\u015f\u0131 b\u0131rakm\u0131\u015f olsak da, ba\u015fka bir tehlike yan\u0131 ba\u015f\u0131m\u0131zda. Havaya sald\u0131\u011f\u0131m\u0131z karbondioksit () gazlar\u0131 her ge\u00e7en g\u00fcn atmosferimizi daha da kal\u0131nla\u015ft\u0131r\u0131p D\u00fcnya i\u00e7indeki s\u0131cakl\u0131\u011f\u0131 artt\u0131r\u0131yor. Bu art\u0131\u015f bu \u015fekilde giderse 50 y\u0131l i\u00e7inde D\u00fcnya\u2019n\u0131n y\u00fczde 10\u2019luk bir b\u00f6lgesinde ya\u015famak imk\u00e2ns\u0131z hale gelecek.<\/p>\n
Bu tehlikenin \u00e7\u00f6z\u00fcm\u00fc o kadar basit de\u011fil. Y\u00fczlerce y\u0131ld\u0131r sahip oldu\u011fumuz ya\u015fam tarz\u0131m\u0131z\u0131 de\u011fi\u015ftirmemiz gerekiyor. Arabalara, k\u00f6m\u00fcre ve petrole ba\u011fl\u0131 olan, kirlilik \u00fcreten end\u00fcstriler var oldu\u011fu m\u00fcddet\u00e7e, k\u00fcresel \u0131s\u0131nma devam edecek. \u00c7\u00f6z\u00fcm ise devlet politikalar\u0131, do\u011fru e\u011fitim ve halk\u0131 bilin\u00e7lendirmede yatmakta.<\/p>\n
\u0130leri okuma i\u00e7in kaynaklar:<\/b><\/p>\n
– http:\/\/www.bbc.com\/news\/science-environment-29152028<\/p>\n
– http:\/\/en.wikipedia.org\/wiki\/Chlorofluorocarbon#Commercial_development_and_use<\/p>\n
–\u00a0http:\/\/en.wikipedia.org\/wiki\/Vienna_Convention_for_the_Protection_of_the_Ozone_Layer<\/p>\n","protected":false},"excerpt":{"rendered":"
1960\u2019l\u0131 y\u0131llarda buzdolaplar\u0131ndan yang\u0131n s\u00f6nd\u00fcrme makinelerine kadar her alanda kullan\u0131lan aletlerin etkisini artt\u0131racak bir organik bile\u015fik ke\u015ffedilmi\u015fti. \u00dcstelik maddenin do\u011faya bilinen hi\u00e7bir zarar\u0131 yoktu. Bu efsane bile\u015fen toplulu\u011funun ismi CFC idi. CFC\u2019ler k\u0131sa s\u00fcrede pop\u00fcler oldu. S\u0131kt\u0131\u011f\u0131m\u0131z deodorantlar\u0131n, sinek ila\u00e7lar\u0131n\u0131n, hatta sa\u00e7 spreylerinin bile i\u00e7ine girmeye ba\u015flam\u0131\u015ft\u0131 1980\u2019lere geldi\u011fimizde. Bir g\u00fcn kutuplarda ara\u015ft\u0131rma yapan bir […]<\/p>\n","protected":false},"author":512,"featured_media":13263,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[165,19,217],"tags":[198,1188,1189],"class_list":["post-117","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-128-sayi","category-bilim-gundemi","category-cevre-bilimleri","tag-cevre","tag-ozon-tabakasi","tag-ultraviyole"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t