Ukushona kwelanga okugqame kakhulu, isibhakabhaka esiguqubele, nezinsuku lapho wonke umuntu ekhwehlela konke kunokuthile okufanayo: konke kungenxa yama-aerosol, izinhlayiya ezincane ezintanta emoyeni. Ama-aerosol angaba amaconsi amancane, izinhlayiya zothuli, izingcezwana zekhabhoni emnyama ecolekile, nezinye izinto ezintanta emkhathini futhi ziguqule wonke amandla eplanethi.
Ama-aerosols anomthelela omkhulu esimweni sezulu seplanethi. Ezinye, njengekhabhoni emnyama nensundu, zifudumeza umkhathi woMhlaba, kanti ezinye, njengamaconsi e-sulfate, ziwupholisa. Ososayensi bakholelwa ukuthi ngokuvamile, wonke ama-aerosols agcina epholisa kancane iplanethi. Kodwa namanje akukacaci ngokuphelele ukuthi lo mphumela wokupholisa unamandla kangakanani nokuthi uqhubeka kangakanani phakathi nezinsuku, iminyaka noma amakhulu eminyaka.
Ayini ama-aerosol?
Igama elithi “i-aerosol” liwukubamba zonke izinhlobo zezinhlayiya ezincane ezilenga emkhathini wonke, kusukela emaphethelweni awo angaphandle kuya phezulu emhlabeni. Zingaba ziqinile noma zibe uketshezi, zibe zincane noma zibe zinkulu ngokwanele ukuba zibonakale ngeso lenyama.
Ama-aerosol “ayinhloko,” njengothuli, umule noma usawoti wasolwandle, aphuma ngokuqondile phezu kweplanethi. Zikhushulelwa emkhathini yimimoya evunguzayo, indiza phezulu emoyeni izintaba-mlilo eziqhumayo, noma ikhishwe ezintukwini zentuthu nemililo. Ama-aerosol “esibili” akhiwa lapho izinto ezihlukahlukene ezintantayo emkhathini—ngokwesibonelo, izakhi eziphilayo ezikhishwa izitshalo, amaconsi e-acid ewuketshezi, noma ezinye izinto—zishayisana, okuholela ekuphenduleni kwamakhemikhali noma ngokomzimba. Ama-aerosol esibili, ngokwesibonelo, adala inkungu okuqanjwe ngayo i-Great Smoky Mountains e-United States.
Ama-aerosol akhishwa kokubili emithonjeni yemvelo kanye ne-anthropogenic. Ngokwesibonelo, kuphuma uthuli ogwadule, osebeni lwemifula eyomile, amachibi omile, neminye imithombo eminingi. Ukugxila kwe-aerosol emkhathini kuyenyuka futhi kwehle ngezenzakalo zesimo sezulu; ngezikhathi ezibandayo, ezomile emlandweni weplanethi, njengenkathi yokugcina yeqhwa, kwakunothuli oluningi emkhathini kunangezikhathi ezifudumele zomlando woMhlaba. Kodwa abantu babe nomthelela kulo mjikelezo wemvelo - ezinye izingxenye zeplanethi zingcoliswe yimikhiqizo yemisebenzi yethu, kanti ezinye zibe manzi ngokweqile.
Usawoti wasolwandle ungomunye umthombo wemvelo wama-aerosol. Zipheshulwa olwandle ngokufuthwa umoya nolwandle futhi zivame ukugcwalisa izingxenye ezingezansi zomkhathi. Ngokuphambene, ezinye izinhlobo zokuqhuma kwentaba-mlilo eziqhuma kakhulu zingadubula izinhlayiya namaconsi phezulu emkhathini ongaphezulu, lapho angantanta khona izinyanga noma ngisho neminyaka, amiswe amamayela amaningi ukusuka ebusweni boMhlaba.
Umsebenzi womuntu ukhiqiza izinhlobo eziningi ezahlukene zama-aerosol. Ukushiswa kwezinto ezimbiwa phansi kukhiqiza izinhlayiya ezaziwa kakhulu ngokuthi amagesi abamba ukushisa - ngaleyo ndlela zonke izimoto, izindiza, izimboni zamandla kanye nezinqubo zezimboni zikhiqiza izinhlayiya ezinganqwabelana emkhathini. Ezolimo zikhiqiza uthuli kanye neminye imikhiqizo efana nemikhiqizo ye-aerosol nitrogen ethinta ikhwalithi yomoya.
Ngokuvamile, izinto ezenziwa abantu ziye zandisa ingqikithi yezinhlayiya ezintanta emkhathini, futhi manje sekunothuli oluphindwe kabili kunolo olwalunjalo ekhulwini le-19. Inani lezinhlayiya ezincane kakhulu (ezingaphansi kwama-microns angu-2,5) wento evame ukubizwa ngokuthi i-“PM2,5” inyuke cishe ngo-60% kusukela kuNguquko Yezimboni. Amanye ama-aerosol, njenge-ozone, nawo aye anda, okunemiphumela emibi kakhulu yezempilo kubantu emhlabeni wonke.
Ukungcoliswa komoya kuye kwaxhunyaniswa nengozi eyengeziwe yesifo senhliziyo, unhlangothi, isifo samaphaphu, nesifo somoya. Ngokwezinye izilinganiso zamuva nje, izinhlayiya ezinhle ezisemoyeni yizo ezibangele ukufa ngaphambi kwesikhathi okungaphezu kwezigidi ezine emhlabeni wonke ngo-2016, futhi izingane kanye nabantu abadala yibona abathinteke kakhulu. Izingozi zezempilo ezivela ekuchayekeni ezinhlayiyeni ezinhle ziphezulu e-China naseNdiya, ikakhulukazi ezindaweni zasemadolobheni.
Ama-aerosols asithinta kanjani isimo sezulu?
Ama-aerosols athinta isimo sezulu ngezindlela ezimbili eziyinhloko: ngokushintsha inani lokushisa elingena noma eliphuma emkhathini, kanye nangokuthinta indlela amafu akha ngayo.
Amanye ama-aerosol, njengezinhlobo eziningi zothuli oluvela ematsheni agayiwe, anombala okhanyayo futhi abonisa ukukhanya kancane. Uma imisebe yelanga iwela phezu kwabo, ibuyisela imisebe emkhathini, ivimbele lokhu kushisa ukuthi kungafinyeleli emhlabeni. Kodwa lo mphumela ungase futhi ube nencazelo embi: ukuqhuma kweNtaba iPinatubo ePhilippines ngo-1991 kwaphonsa endaweni ephakeme i-stratosphere inani lezinhlayiya ezincane ezibonisa ukukhanya ezazilingana nendawo engamakhilomitha-skwele angu-1,2, okwathi kamuva kwabangela ukupholisa kweplanethi okungazange kume iminyaka emibili. Futhi ukuqhuma kwentaba-mlilo yaseTambora ngo-1815 kwabangela isimo sezulu esibanda ngendlela engavamile eNtshonalanga Yurophu naseNyakatho Melika ngo-1816, yingakho yaqanjwa ngokuthi “Unyaka Ngaphandle Kwehlobo” - kwakubanda futhi kumnyama kangangokuthi kwaze kwaphefumulela uMary Shelley ukuba ambhalele isiGothic. inoveli Frankenstein.
Kodwa amanye ama-aerosol, njengezinhlayiya ezincane zekhabhoni emnyama emalahleni ashile noma ngokhuni, asebenza ngokuhlukile, amunca ukushisa kwelanga. Lokhu kugcina kufudumeza umkhathi, nakuba kupholisa ubuso boMhlaba ngokunciphisa imisebe yelanga. Ngokuvamile, lo mphumela cishe ubuthakathaka kunokupholisa okubangelwa amanye ama-aerosols amaningi - kodwa ngokuqinisekile unomphumela, futhi uma i-carbon material inqwabelana emkhathini, yilapho umkhathi ushisa kakhulu.
Ama-aerosols aphinde abe nomthelela ekubunjweni nasekukhuleni kwamafu. Amaconsi amanzi ahlangana kalula ezinhlayiyeni, ngakho umoya ocebile ngezinhlayiya ze-aerosol uthanda ukwakheka kwamafu. Amafu amhlophe abonisa imisebe yelanga engenayo, eyivimbela ukuba ifinyelele phezulu futhi ifudumeze umhlaba namanzi, kodwa futhi amunca ukushisa okukhishwa njalo yiplanethi, akuvale emkhathini ophansi. Ngokuya ngohlobo nendawo yamafu, angafudumeza indawo ezungezile noma apholise.
Ama-aerosol anesethi eyinkimbinkimbi yemithelela ehlukene emhlabeni, futhi abantu baye baba nomthelela ngokuqondile ukuba khona kwawo, ubuningi, nokusatshalaliswa kwawo. Futhi nakuba imithelela yesimo sezulu iyinkimbinkimbi futhi iguquguquka, imithelela empilweni yomuntu icacile: lapho izinhlayiya ezinhle kakhulu ezisemoyeni, kulapho kulimaza kakhulu impilo yomuntu.