The Econmist - USA (2021-10-30)

4 SpecialreportStabilisingtheclimate TheEconomistOctober30th 2021

sheetsofGreenlandandwesternAntarcticaandmakingiteasier

formidsizedhurricanestointensifyintothemostpowerfulof

storms.Itisalsomakingitharderfornutrientsatdepthtogetto

thelivingthingsthatdependonthemclosetothesurfaceandre­

ducingoxygenlevels.Sealevelsarerisingbya centimetreevery

threeyearsorso.

Ifthiswerea continentalrearrangement,itwouldbea global

tectonicspasmwhichmovedallthecontinentsandtheirhapless

inhabitantsawayfromthepolesandtowardstheequatorwhile,at

thesametime,pushingonce­coolmountainheightsdownto­

wardsswelteringplainsandonce­stablecoastlinesbeneaththe

waves.Andit wouldbepickingupspeed.

ThereisnodoubtthatthechangeintheCO 2 levelwasbrought

aboutbyhumankind—mainlythroughtheburningoffossilfuels,

butalsothroughconversionofforestsandothernaturalecosys­

temstofarmland.Aslongasthoseactivitiescontinueintheircur­

rentform,theCO 2 levelwillcontinuetorise,andtheworldwill

movefurtherandmoredamaginglyawayfromitshistoricalstate.

In1992,whentheCO 2 levelhadreached356ppm andevidence

ofanthropogenicwarmingwas,ifnotoverwhelming,definitely

discernible,theleadersoftheworldagreedtodosomethingabout

thepotentiallycatastrophiccoursetheyhadmoreorlessunwit­

tinglyembarkedon.IntheunFrameworkConventiononClimate

Change(unfccc) agreeduponata summitinRiodeJaneirothat

year,theycommittedthemselvestothe“stabilisationofgreen­

house­gasconcentrationsintheatmosphereata levelthatwould

preventdangerousanthropogenicinterferencewiththeclimate

system”.Thiswastobedoneina “time­framesufficienttoallow

ecosystemstoadaptnaturallytoclimatechange,toensurethat

foodproductionisnotthreatenedandtoenableeconomicdevel­

opmenttoproceedina sustainablemanner”.

Thiswas,byfar,themostambitiousinternationalagreement

ofalltime.Thereisnowayofstabilisingtheclimatewithoutstop­

pingtheincreaseinthelevelsoflong­livedgreenhousegasesin

theatmosphere.Althoughit didnotsaysoinsomanywords—ma­

nymightnothavesignedupifithad—theunfccchad,ineffect,

committeditssignatoriestoendingthefossil­fuelage.

Anewera

Fossil fuels have been crucial to the development of the economy

for two centuries. They played an intimate part in the most impor­

tant  transformation  in  the  human  condition  since  the  develop­

ment of agriculture, a transformation that saw a huge growth both

in the world’s population and in people’s wealth. But their use also

gave  the  CO 2 level,  previously  part  of  the  background  against

which the human drama played out, a potentially show­stealing,

orevenshow­ending,role.Ithadtobebroughtundercontrol.It

hadtobestabilised.

Whiletheseremarkableaspirationsfloatedfreeofspecifictar­

gets,thesheermagnitudeofthetaskcouldbeignored,andig­

noreditlargelywas.In 2015 inParis,thesamegroupofcountries

tetheredtheiraspirationstoa setofspecificgoals,therebyreveal­

ingthebrutalsizeoftheundertaking.“Preventingdangerousan­

thropogenicchange”,saidtheParisagreement,meantinpractice,

“holdingtheincreaseintheglobalaveragetemperaturetowellbe­

low2°Cabovepre­industriallevelsandpursuingeffortstolimit

thetemperatureincreaseto1.5°Cabovepre­industriallevels”.As

tothetimeframe,thepeakingreenhouse­gasemissionsshould

comeabout“assoonaspossible”,thereshouldbe“rapidreduc­

tionsthereafter”,and“abalancebetweenanthropogenicemis­

sionsbysourcesandremovalsbysinksofgreenhousegases”(net­

zeroemissions)shouldbeachievedby“thesecondhalfofthis

century”—ie,inconsiderablylessthana humanlifespan.

AsthepartiestotheunfcccconvergeonGlasgowforthecop

26 summit, this special report looks at what those commitments

mean. It is not a guide to the specifics of carbon­cutting policies

and  technologies,  nor  to  the  particular  ways  in  which  national

commitments  made  in  Glasgow  will  fall  short  of  the  ambition

needed.  It  is  a  survey  of  the  scale  of  action  required,  the  battle­

ground on which it will be fought and the fundamental novelty of

undertaking to stabilise the climate. 

The  moment  when  the  CO 2 level,  so  flat  for  so  long,  began  to

rise was the inadvertent beginning of a new era in which the in­

dustrial economy and the forces of nature became conjoined. The

moment when the now perilously steep curve rounds the corner

to a new plateau, or even a steady decline, will be as consequential.

But the agreements in Rio and Paris say that this time it will not be

inadvertent. The curve­flattening climate stabilisation will be the

result of deliberate interventions in both the economy and nature

on a global scale. And it will be maintained, if itismaintained, by

human institutions with the astonishing, andpossibly hubristic,

mandate of long­term atmospheric management.n

The great right angle

Global atmospheric CO2 concentration, parts per million

Sources:OurWorldinData; NOAA

4000 2000

450

400

350

300

250

150010005001500100015002000250030003500

Pre-industrial range

BC AD

State of play

The Paris challenge

T

hatit tookalmost a quarter of a century of diplomatic wran­

gling,  setbacks  and  innovation  for  the  world  to  put  Paris’s

numbers  and  procedures  to  Rio’s  remarkable  ambition  makes  it

unsurprising that, as yet, little has been done to meet its goals. In

1992,  according  to  figures  from  Our  World  in  Data,  78%  of  the

world’s  primary  energy—the  stuff  used  to  produce  electricity,

drive  movement  and  provide  heat  both  for  industrial  purposes

and to warm buildings—came from fossil fuels. By 2019 the total

amount of primary energy used had risen by 60%. And the propor­

tion provided by fossil fuels was now 79%. 

Over the same period the share of primary energy provided as

electricity by modern renewables—wind turbines and solar pan­

els—rose from nothing to 3%. The share provided by nuclear pow­

er, which is also generated without fossil fuels, fell from 5.4% to

4%. Hydroelectricity was more or less stable at 6%.

Luckily, not all trends are linear. The highly subsidised growth

in renewables that began to take off in the early 2000s has not yet

Replacing fossil fuels is becoming easier. But temperatures

are still likely to rise too far