农资网> 技术 >正文

温室效应能阻止冰川期到来吗

发布时间：2024-10-26 09:44:15 来源：农资网编辑：郑钦文本文有91个字，大约阅读时间1分钟

作者

如果你看过动画片《冰河时代》，一定对那番冰天雪地的场景记忆犹新。最新研究显示，数万年之后，地球又将进入冰川期，整个北半球都将被厚厚的冰雪覆盖。那么现在最让人们头疼的

温室效应

能阻止下一个冰川期的来临吗？

Emissionsofgreenhousegases—suchasthecarbondioxide,orCO2,thatcomesfrompowerplantsandcars—areheatingtheatmospheretosuchanextentthatthenexticeage,predictedtobethedeepestinmillionsofyears,

may

bepostponedindefinitely.

Inabout10,000to100,000years,thestudysuggests,Antarctic-like"permanent"icesheetswouldshroudmuchofCanada,Europe,andAsia."Ithinkthepresentcarbondioxidelevelsareprobablysufficienttopreventthatfromeverhappening,"saidCrowley,whosestudywillappeartomorrowinthejournalNature.

Forthepastthreemillionyears,Earth'sclimatehaswobbledthroughdozensoficeages,withthickicesheetsgrowing

from

thepolesandthenshrinkingbackagain.Theseiceagesusedtolastroughly41,000years.Butinthepasthalfamillionyears,thesebigfreezeseachstretchedtoaboutahundredthousandyearslong.Meanwhile,thetemperatureswingsduringandbetweentheseiceagesbecamemoreextreme,soaringtonewhighsandlows.Theseextremeclimateswingsdon'tappeartobeeasinganytimesoon,accordingtoevidencerecordedinEarth'srocks,Crowleysaid."Thelatesttwoglaciationsweretwoofthebiggestwe'veseen."

Theresearchersfoundthatbetween10,000and100,000years

from

now,Earthwouldenterintoaperiodofpermanenticesheets—moreseverethananyseeninmillionsofyears.Thoughthisextremeiceagewouldbeunusual,soistheclimatethatpeoplearecreatingbyemittinghugeamountsofgreenhouse

gas

es,Crowleysaid(

global

warmingfastfacts)."It'shardtosaywhat'sgoingtohappen,"Crowleysaid."The

very

factthatyouhavethisnon-glacialatmospherewithpolaricecaps,presentsabizarrescenario.Prehistoric-climateexpertLorraineLisieckisaid,"Thisisthe

only

studyofwhichIamawarethatsuggeststhenexticeagecouldbemuchmoreextremethanthoseofthepreviousonemillionyears."

Manymoretestsareneededtoseeifthestudy'spredictionseemscorrect,saidLisiecki,oftheUniversityofCalifornia,SantaBarbara.Butsheagreedthatwemightneverfindoutwhatwouldhavehappenednaturally,duetohuman-caused

global

warming."Currentgreenhouse

gas

concentrationsareprobablysimilartothosethatoccurredthreemillionyearsagoandarehighenoughtopreventaniceageforhundredsofthousandsofyears,"shesaid.

阅读全文

分享空间
分享微博
手机扫一扫

上一篇：南瓜脯的加工方法下一篇：马铃薯虾片的加工技术

温室效应能阻止冰川期到来吗

推荐阅读

最新更新

合作伙伴