SHORTLYAFTER6pmonSeptember9th,theOrcacarbon-captureplant,justoutsideReykjavikinIceland,switchedonitsfansandbegansuckingcarbondioxidefromtheair.Thesoundwassubtle-abitlikeagurglingstream.Buttheplantscreatorshopeitwillmarkabigshiftinhumanitysinteractionwiththeclimate.

九月九日下午六点刚过，位于冰岛首都雷克雅未克城外的奥卡（Orca）碳捕获工厂启动了风扇，开始从空气中吸收二氧化碳。风扇的声音不大，有点像汩汨的流水声。但这家工厂的创建者希望这将是人类与气候的关系中一个重大的转折点。

Orcais,fornow,thelargestinstallationintheinfant"directaircapture"industry,whichaimstoremoveCO2fromtheatmosphere.WhensealedundergroundsuchCO2countsas"negativeemissions"—anessentialbutunderdevelopedmethodfortacklingglobalwarming.Tostoptemperaturesrisingby1.5℃oreven2℃abovepre-industrialaverages,aspertheParisclimateagreement,hundredsorthousandsofbillionsoftonnesofCO2willhavetoberemovedfromtheatmosphereinthesecondhalfofthecentury.

想要从大气中去除二氧化碳的"直接空气捕获行业正处于萌芽阶段，奥卡目前是此类工厂中规模最大的一间。捕获到的二氧化碳被封存于地底之后，就被记作"负排放"--这是应对全球变暖的一种重要但尚不成熟的方法。根据《巴黎气候协定》，为了避免气温比工业化前平均水平升高1.5甚至2摄氏度，必须在本世纪下半叶从大气中移除数千亿乃至上万亿吨的二氧化碳。

Currently,theonlymeansofdoingthatisplantingtrees,anoptionthatisnotentirelywithoutdrawbacks.Treesburninwildfiresandcanbecutdown.Whenthishappens,muchofthecarbontheystoreescapes.TheOrcaplantshowsanotherway.Climeworks,the