Possible artifacts of data biases in the recent global surface warming hiatus

46 Pages·2015·6.44 MB·English

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scriptomeanalysisindicatesthatAlma1isbyfar 13. M.A.Moran,C.R.Reisch,R.P.Kiene,W.B.Whitman, S.Rosenwasserforimportantinsightsregardingthetranscriptome
themosthighlyexpressedAlmageneinHL373 Annu.Rev.Mar.Sci.4,523–542(2012). denovoconstruction,U.Sheynforassistancewiththeexperimental
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withAlma3/6andAlma7(CladeA)beingmost 16. BLi.mAn.oRl.eOadceeatnoagl.r,.N3a6t,u6re294–9694,320(199–9211)3.(2013). RS..GHraasfhfafoyervthfeorgrteacphhnicicdaelsaigssni.sWtaencgerawteitfhulflyraacctikonnoawtiloend,gaenfdinancial
closelyrelatedtoAlmagenesfromPhaeocystis 17. M.Steinke,G.V.Wolfe,G.O.Kirst,Mar.Ecol.Prog.Ser.175, supportfromtheSassonandMarjoriePeressPhilanthropic
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inthesupplementarymaterials.Transcriptomesequencesare
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alsoincludeskeyalgalspeciesthatareknownto (1996). PRJNA283462.Authorcontributions:U.A.,D.S.T,andA.V. 0000
p(eo.gss.,eSsysmhibgihodDinMiuSPmlyspas.,eaaccotirvailtys,ymdinbioofnlatg),eolltahteesr 20.J(1.9S9t6e)fe.ls,L.Dijkhuizen,Mar.Ecol.Prog.Ser.131,307–313 cdoantac,eaivneddwthroeteprtohjeecpt,adpeesr.igUn.eAd.ptheerfoerxmpeerdimtheentesx,paenraimlyzeendtst.he 6, 26, 26, 26, 2
S.B.-D.andE.F.performedthetranscriptomeanalyses.Y.L. 2222
haptophytes(e.g.,Prymnesiumparvum)(20,30), 21. M.K.Nishiguchi,L.J.Goff,J.Phycol.31,567–574 performedtheshotgunproteomics. r r r r
andcoralorthologs(Acroporamillepora).Although (1995). bebebebe
DMSPcanalsobeproducedbycorals(31),DMSP 22.BAq.uRa.tM.Boihoal.p1a8tr,a1,8A5.–N19.5Re(2lli0n1g3e)r.,D.J.Kieber,R.P.Kiene, SUPPLEMENTARYMATERIALS emememem
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symbiotic algaeand/orassociated bacteria and 24.B.R.Lyon,P.A.Lee,J.M.Bennett,G.R.DiTullio, MaterialsandMethods NoNoNoNo
n4Aot),wseitvherthaleAclomraaligtesnelefs(3w2e)r.eWfoituhnindctloadheavBe(tFwigo. 25.UDM...SAG.l.cToJalaownmeficbkh,ri,B,PiPol.acnhLtaemuPrhiisnytosr,iyoPl5..31L,5a75r,4a71-A93s2–t65ia–4s17o95,4A(12.(0V210a4r1)d1.)i,. FTRiaegbfsel.ereSsn1Sct1eostoS(13S033–41) on g on g on g on g
Alma1-likedomainsfusedintandem,including 26.J.D.Toddetal.,Science315,666–669(2007). 19March2015;accepted15May2015 orororor
E.huxleyi Alma4/5andtheChrysochromulina 27.P.vonDassowetal.,GenomeBiol.10,R114(2009). 10.1126/science.aab1586 g.g.g.g.
polylepis gene. Clade C (Fig. 4A) includes E. aaaa
mmmm
huxleyiAlma1andAlma2thatalsoappearinthe eeee
closelyrelatedIsochrysis.Themoredistantclade cccc
nnnn
Dcomprisesbacterialgeneswith~30%identity CLIMATECHANGE eeee
to Alma1, but its relevance is yet to be deter- scisciscisci
mined. We synthesized five genes from across Possible artifacts of data biases in the w.w.w.w.
thephylogenetictreeandexpressedtheminE.coli wwww
wwww
(seetheSM).Twogenes,E.huxleyiAlma2(clade recent global surface warming hiatus m m m m
C)andSymbiodinium-A1(cladeA)wereexpressed oooo
afetedloiwnglDevMelSs,PyteotEe.xchoilbiitceudltulyraese(fiagc.tSiv10it)y.Hupoown- ed fred fred fred fr
ever, these two enzymes were not sufficiently ThomasR.Karl,1*AnthonyArguez,1BoyinHuang,1JayH.Lawrimore,1 dddd
aaaa
stabletobepurified. JamesR.McMahon,2MatthewJ.Menne,1ThomasC.Peterson,1 oooo
The identification of the family members of RussellS.Vose,1Huai-MinZhang1 wnlwnlwnlwnl
thenewlyidentifiedalgalDMSPlyaseinawide oooo
DDDD
rangeofmarineorganismswouldenablebetter Muchstudyhasbeendevotedtothepossiblecausesofanapparentdecreaseinthe
understandingofthephysiologicalandsignaling upwardtrendofglobalsurfacetemperaturessince1998,aphenomenonthathasbeen
rolesofDMSinalgalresistancetoviralinfection, dubbedtheglobalwarming“hiatus.”Here,wepresentanupdatedglobalsurface
predation(5),andcommensal(14)andsymbiotic temperatureanalysisthatrevealsthatglobaltrendsarehigherthanthosereportedbythe
interaction (31). Although it is clear that DMS IntergovernmentalPanelonClimateChange,especiallyinrecentdecades,andthatthe
productionbybacteriaDMSPlyaseshasafun- centralestimatefortherateofwarmingduringthefirst15yearsofthe21stcenturyis
damentalroleintheoceanicsulfurandcarbon atleastasgreatasthelasthalfofthe20thcentury.Theseresultsdonotsupportthe
cycles,thenewlyrevealedalgalenzymemayal- notionofa“slowdown”intheincreaseofglobalsurfacetemperature.
T
lowquantificationoftherelativebiogeochemical
contributionofalgaeandbacteriatotheglobal he Intergovernmental Panel on Climate a“hiatus”andinspiredasuiteofphysicalex-
DMSproduction. Change (IPCC) Fifth Assessment Report planationsforitscause,includingchangesin
(1)concludedthattheglobalsurfacetem- radiativeforcing,deepoceanheatuptake,and
REFERENCESANDNOTES perature“hasshownamuchsmallerin- atmosphericcirculationchanges(2–12).Although
1. W.Sunda,D.J.Kieber,R.P.Kiene,S.Huntsman,Nature418, creasinglineartrendoverthepast15years these analyses and theories haveconsiderable
317–320(2002). [1998–2012]thanoverthepast30to60years.” meritinhelpingtounderstandtheglobalclimate
2. E.Garcés,E.Alacid,A.Reñé,K.Petrou,R.Simó,ISMEJ.7,
1065–1068(2013). The more recent trend was “estimated to be system,otherimportantaspectsofthe“hiatus”
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(2012). tention.Inparticular,residualdatabiasesinthe
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(1997). (NOAA),NationalCentersforEnvironmentalInformation
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26793–26808(2000). *Correspondingauthor.E-mail:[email protected] wasshortandcommencedwithastrongElNiño
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Fig.1.Effectofnew
Global Ocean Land
analysisonglobal
surfacetemperature
trendsforseveral de)0.3
a
periods.Temperature c
e
trendsareshownfor d
datawiththe“new” C/0.2
°
analysis(squares) s (
and“old”analysis nd0.1
e
(pceirrcioledss)offorinsteevreesrat.l ure tr 0
Alsoindicatedare at
globalvalues er
p-0.1
calculatedwiththe m
newcorrectionsand Te Base “Hiatus” Second 21st C 1998 Base “Hiatus” Second 21st C 1998 Base “Hiatus” Second 21st C 1998
thepolarinterpolation period half of to 2014 period half of to 2014 period half of to 2014
20th C 20th C 20th C
method(triangles).
Consistentwiththe (A)1951 (B)1998 (C)1950 (D)2000 (E)1998 (A)1951 (B)1998 (C)1950 (D)2000 (E)1998(A)1951 (B)1998 (C)1950 (D)2000 (E)1998
IPCCreport(1),the to 2012 to 2012 to 1999 to 2014 to 2014 to 2012 to 2012 to 1999 to 2014 to 2014 to 2012 to 2012 to 1999 to 2014 to 2014
errorbarsrepresent IPCC Periods Other Periods IPCC Periods Other Periods IPCC Periods Other Periods
the90%confidence
intervals(CIs).Theadditionalerrorassociatedwithuncertaintyofourcorrectionsextendsthe90%CIandisdepictedwithahorizontaldash.(AandB)
Thebaseperiod(1951–2012)and“hiatus”periodusedinIPCC(1).(C)Analternatebaseperiod,thesecondhalfofthe20thcentury.(D)The21stcentury
through2014.(E)1998(astrongElNiñoyear)throughthe21stcentury.SourcedataareprovidedintableS1.
in1998.Givenrecentimprovementsintheob- New corrections versus old corrections
gselorvbeadldraetcao(ridnc(l1u3d,i1n4g)aarnedcoarddd-witiaornmal20ye14ar),swoef C) 0.5
° New corrections
reexamine the observational evidence related y (
toa“hiatus”inrecentglobalsurfacewarming. al Old corrections
m
Thedatausedinourlong-termglobaltemper- o 0
n
atureanalysisprimarilyinvolvesurfaceairtem- a
perature observations taken at thousands of e
ur
weather-observingstationsoverland,andfor at−0.5
coverageacrossoceans,thedataareseasurface er
p
temperature(SST)observationstakenprimar- m
ilybythousandsofcommercialshipsanddrifting Te −1
surface buoys. These networks of observations 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Year
arealwaysundergoingchange.Changesofpar-
ticular importance include (i) an increasing
With new corrections versus without corrections
amount of ocean data from buoys, which are
slightly different than data from ships; (ii) an C) 0.5
° With corrections
itnakcreeathsienrgmaommoeutenrts,owfshhiciphdaaretasflirgohmtlyendgififneereinnt- aly ( Without corrections
m
than data from bucket seawater temperatures; 0
o
and(iii)alargeincreaseinland-stationdata, n
a
whichenablesbetteranalysisofkeyregionsthat e
maybewarmingfasterorslowerthantheglobal atur−0.5
average.Weaddressallthreeofthese,noneof er
whichwereincludedinourpreviousanalysis mp
usedintheIPCCreport(1). e
T −1
First,severalstudieshaveexaminedthediffer- 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
encesbetweenbuoy-andship-baseddata,noting Year
that the ship data are systematically warmer Fig.2.Global(landandocean)surfacetemperatureanomalytimeserieswithnewanalysis,old
than the buoy data (15–17). This is particularly analysis,andwithandwithouttime-dependentbiascorrections.(A)Thenewanalysis(solidblack)
important because much of the sea surface is comparedwiththeoldanalysis(red).(B)Thenewanalysis(solidblack)versusnocorrectionsfortime-
now sampled by both observing systems, and dependentbiases(blue).
surface-driftingandmooredbuoyshaveincreased
theoverallglobalcoveragebyupto15%(supple- calculatingtheaveragedifferencebetweencollo- generally, buoy data have been proven to be
mentarymaterials).Thesechangeshaveresulted catedbuoyandshipSSTs.Theaveragedifference moreaccurateandreliablethanshipdata,with
inatime-dependentbiasintheglobalSSTrecord, globallywas−0.12°C,acorrectionthatisapplied better-known instrument characteristics and
andvariouscorrectionshavebeendevelopedto to the buoy SSTs at every grid cell in ERSST automatedsampling(16).Therefore,ERSSTver-
accountforthebias(18).Recently,anewcorrec- version4.[IPCC(1)usedaglobalanalysisfromthe sion 4 also considers this smaller buoy uncer-
tion (13) was developed and applied in the Ex- UKMetOfficethatfoundthesameaverageship- taintyinthereconstruction(13).
tended Reconstructed Sea Surface Temperature buoydifferenceglobally,althoughthecorrections Second,therewasalargechangeinshipob-
(ERSST)datasetversion4,whichweusedinour appliedinthatanalysiswereequaltodifferences servations(frombucketstoengineintakether-
analysis.Inessence,thebiascorrectioninvolved observedwithineachoceanbasin(18).]More mometers)thatpeakedaroundWorldWarII.The
1470 26JUNE2015(cid:127)VOL348ISSUE6242 sciencemag.org SCIENCE
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hibitsmorethantwiceasmuchwarmingasdid
Global Ocean Land
theoldanalysisattheglobalscale(0.086°versus
7950 0.039°C decade−1) (table S1). This is clearly at-
60 tributabletothenewSSTanalysis,whichitself
hasmuchhighertrends(0.075°versus0.014°C
45 decade−1).Incontrast,trendsinthenewLST
analysisareonlyslightlyhigher(0.117°versus
30 0.112°Cdecade−1).
IPCC(1)acknowledgedthattrendssince1998
weretenuousbecausetheperiodwasshortand
15
commenced with a strong El Niño. Two addi-
e tionalyearsofdataarenowavailabletorevisit
d
atitu 0 tthreisndpsocionmt,pinucteluddtihnrgouaghre2c0o1r4d-cwoanrfmirm20th1e4,IPaCnCd
L supposition. Specifically, the centraltrend esti-
-15 mateinournewanalysisfor1998–2014is0.020°C
decade−1higherascomparedwith1998–2012.Like-
1950-1999 wise, global trends for 2000–2014 are 0.030°C
-30 2000-2014 decade−1higherthanfor1998–2012.Inotherwords,
changingthestartandenddateby2yearsdoes
-45 infacthaveanotableimpactontheassessment
oftherateofwarming,butlesscomparedwiththe
-60
impactofnewtime-dependentbiascorrections.
-75
-90 Our analysis also suggests that short- and
long-term warming rates are far more similar
-0.2 0 0.2 0.4 0.6 -0.2 0 0.2 0.4 0.6 -0.4-0.2 0 0.2 0.4 0.6 0.8
than previously estimated in IPCC’s report (1).
Trend (°C/decade) Trend (°C/decade) Trend (°C/decade)
Thedifferencebetweenthetrendsintwoperiods
Fig.3.Latitudinalprofilesofsurfacetemperaturetrends.Zonalmeantrendsandstatisticaluncer- usedinIPCC’sreport(1998–2012and1951–2012)
taintyofthetrendestimatesforglobal,ocean,andlandsurfacetemperature,averagedin30°latitudinal (1)isanillustrativemetric:Thetrendsforthese
belts,forthesecondhalfofthe20thcentury(dashed)comparedwiththepast15years(solid).Trends twoperiodsinthenewanalysisdifferby0.043°C
are cosine-weighted within latitudebelts,and thevertical axis is ona sinescaleso as toreflect the decade−1comparedwith0.078°Cdecade−1inthe
proportionalsurfaceareaofthelatitudebands.Onlytheuncertaintyrelatedtothetrendestimatesis old analysis reported by IPCC (1). The smaller
providedbecausezonalstandarderrorsofestimatearenotavailableincontrasttotheglobalaverages. differenceresultsfrommorewarminginthenew
ocean analysis since 1998, reflecting the im-
previousversionofERSSTassumedthatnoship dependentbiascorrections,andotherdatapro- provedbiascorrectionsinERSSTversion4.The
corrections were necessary after this time, but cessingsteps(21)totheISTIdatabankinorder newcorrectionsshowthatthe90%confidence
recentlyimprovedmetadata(18)revealthatsome toaddressartificialshiftsinthedatacausedby interval for 1998–2012 encompasses the best
shipscontinuedtotakebucketobservationseven changesin,forexample,stationlocation,tem- estimateofthetrendfor1951–2012.
uptothepresentday.Therefore,oneoftheim- perature instrumentation, observing practice, Also, the new global trends are statistically
provementstoERSSTversion4isextendingthe urbanization,andsitingconditions.Thesecor- significantandpositiveatthe0.10 significance
ship-bias correction to the present, based on in- rectionsareessentiallythesameasthoseusedin levelfor1998–2012(Fig.1andtableS1)byusing
formationderivedfromcomparisonswithnight theGHCN–Monthlyversion3dataset(22,23), theapproachdescribedin(25)fordetermining
marine air temperatures. Of the 11 improve- whichisupdatedoperationallybytheNational trenduncertainty.Incontrast,the IPCCreport
mentsinERSSTversion4(13),thecontinuation Oceanographic and Atmospheric Administra- (1),whichalsousedtheapproachin(25),reported
oftheshipcorrectionhadthelargestimpacton tion’s(NOAA’s)NationalCentersforEnviron- nostatisticallysignificanttrendsfor1998–2012in
trendsforthe2000–2014 timeperiod,account- mentalInformation(NCEI).Toobtainournew anyofthethreeprimaryglobalsurfacetemper-
ingfor0.030°Cofthe0.064°Ctrenddifference global analysis, the corrected ISTI land data aturedatasets.Moreover,for1998–2014ournew
withversion3b.[Thebuoyoffsetcorrectioncon- (14) were systematically merged with ERSST globaltrendis0.106°T0.058°Cdecade−1,andfor
tributed0.014°Cdecade−1tothedifference,and version4(13),asdescribedinthesupplemen- 2000–2014,itis0.116°T0.067°Cdecade−1(table
theadditionalweightgiventothebuoysbecause tarymaterials. S1).Thisissimilartothewarmingofthelasthalf
of their greater accuracy contributed 0.012°C In addition to the three improvements just ofthe20thcentury(Fig.1).Amorecomprehen-
decade−1(supplementarymaterials).] discussed,sincetheIPCCreport(1)newanalyses sive approach for determining the 0.10 signifi-
Third,therehavealsobeenadvancementsin (24)haverevealedthatincompletecoverageover cance level (supplementary materials), which
thecalculationoflandsurfaceairtemperatures theArctichasledtoanunderestimateofrecent alsoaccountsfortheimpactofannualerrorsof
(LSTs).Themostimportantisthereleaseofthe (since1997)warmingintheHadleyCentre/Climate estimateonthetrend,showsthatthe1998–2014
International Surface Temperature Initiative ResearchUnitdatausedintheIPCCreport(1). and2000–2014trends(butnot1998–2012)were
(ISTI)databank(14,19),whichformsthebasis These analyses have surmised that incomplete positiveatthe0.10significancelevel.
oftheLSTcomponentofournewanalysis.The Arcticcoveragealsoaffectsthetrendsfromour For the full period of record (1880–present)
ISTIdatabankintegratestheGlobalHistorical analysisasreportedbyIPCC(1).Weaddressthis (Fig.2),thenewglobalanalysishasessentially
ClimatologyNetwork(GHCN)–Dailydataset(20) issueaswell. thesamerateofwarmingasthatoftheprevious
withmorethan40otherhistoricaldatasources, Temperature trends in our old analysis and analysis(0.068°Cdecade−1and0.065°Cdecade−1,
morethandoublingthenumberofstationsavail- ournewanalysisaredepictedinFig.1,supple- respectively) (table S1), reinforcing the point
able. The resulting integration improves spatial mentedwithpolarinterpolation.(Inthisdiscus- thatthenewcorrectionsmainlyhaveanimpact
coverage over many areas, including the Arctic, sion,“old”referstotheanalysisbasedonERSST inrecentdecades.However,itisalsoclearthat
wheretemperatureshaveincreasedrapidlyinre- version3bforoceanareasandGHCN–Monthly thelong-termtrendwouldbesignificantlyhigher
centdecades(1).Weappliedthesamemethods version 3 for land areas). For the most recent (0.085°Cdecade−1)(Fig.2B)withoutcorrections
usedinouroldanalysisforqualitycontrol,time- IPCC period (1998–2012), the new analysis ex- forotherhistoricalbiases,asdescribedin(26).
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shorttime-scalezonaltrends.Itisevidentthatin 19. J.H.Lawrimore,J.J.Rennie,P.W.Thorne,Eos94,61(2014). TableS1
mostlatitudebands,theglobaltrendsinthepast 20.MJ..AJt.mMoesn.nOec,eIa.nD.uTrreec,hRno.lS..2V9o,s8e9,7B–.9E1.0G(le2a0s1o2n).,T.G.Houston, References(28–38)
15yearsarecomparablewithtrendsinthepre- 21. M.J.Menne,C.N.WilliamsJr.,J.Clim.22,1700–1717(2009). 23December2014;accepted21May2015
ceding50years. 22.J.H.Lawrimoreetal.,J.Geophys.Res.116(D19),D19121 Publishedonline4June2015;
Last,weconsideredtheimpactoflargerwarm- (2011). 10.1126/science.aaa5632
ingratesinhighlatitudes(24)ontheoverall
globaltrend.Toestimatethemagnitudeofthe
additionalwarming,weappliedlarge-areainter- BRAINCIRCUITS
polationoverthepolesusingthelimitedobserva-
tionaldataavailable.Resultsindicatethat,indeed,
A parvalbumin-positive excitatory
additionalglobalwarmingofafewhundredthsof
adegreeCelsiusperdecadeoverthe21stcentury
is evident (Fig. 1), providing further evidence visual pathway to trigger fear
againstthenotionofarecentwarming“hiatus”
(supplementarymaterials). responses in mice
Newly corrected and updated global surface
temperature data from NOAA’s NCEI do not
supportthenotionofaglobalwarming“hiatus.”
CongpingShang,1,2ZhihuiLiu,1ZijunChen,1,2YingchaoShi,1,2QianWang,1
AsshowninFig.1,thereisnodiscernable(sta-
SuLiu,1DapengLi,1PengCao1*
tistical or otherwise) decrease in the rate of
warming between the second half of the 20th
Thefearresponsestoenvironmentalthreatsplayafundamentalroleinsurvival.Littleis
centuryandthefirst15yearsofthe21stcentury.
knownabouttheneuralcircuitsspecificallyprocessingthreat-relevantsensoryinformation
Ournewanalysisnowshowsthatthetrendover
inthemammalianbrain.Weidentifiedparvalbumin-positive(PV+)excitatoryprojection
the period 1950–1999, a time widely agreed as
neuronsinmousesuperiorcolliculus(SC)asakeyneuronalsubtypefordetectinglooming
having significant anthropogenic global warm-
ing (1), is 0.113°C decade−1, which is virtually objectsandtriggeringfearresponses.Theseneurons,distributedpredominantlyinthe
superficialSC,divergentlyprojectedtodifferentbrainareas,includingtheparabigeminal
indistinguishablefromthetrendovertheperiod
2000–2014 (0.116°C decade−1). Even starting a nucleus(PBGN),anintermediatestationleadingtotheamygdala.ActivationofthePV+
SC-PBGNpathwaytriggeredfearresponses,inducedconditionedaversion,andcaused
trendcalculationwith1998,theextremelywarm
depression-relatedbehaviors.Approximately20%ofmicesubjectedtothefear-
ElNiñoyearthatisoftenusedasthebeginning
conditioningparadigmdevelopedageneralizedfearmemory.
of the “hiatus,” our global temperature trend
(1998–2014)is0.106°Cdecade−1—andweknow E
thatisanunderestimatebecauseofincomplete nvironmentalthreatsaredetectedbydif- Withanoptogeneticapproach(12–14),wefound
coverageovertheArctic.Indeed,accordingtoour ferentsensoryorgansprojectingtocentral that activation of neurons expressing channel-
newanalysis,theIPCC’s(1)statementof2years brainareastotriggerfearresponses(1,2). rhodopsin-2(ChR2)inmouseSCtriggeredfreez-
ago—thattheglobalsurfacetemperature“has Thesuperiorcolliculus(SC)isaretinalre- ingthatlasted52.8T5.3s(n=5mice)(movie
shownamuchsmallerincreasinglineartrend cipientstructure(3,4)composedofdifferent S1). This prompted us to systematically iden-
overthepast15yearsthanoverthepast30to neuronal subtypes (5, 6), including parvalbumin- tifythekeyneuronalsubtypesunderlyingthis
60years”—isnolongervalid. positive(PV+),somatostatin-positive (SST+), and behavior.
vasoactiveintestinalpeptide–positive(VIP+)neu- BycrossingAi32(15)withdifferentCrelines
REFERENCESANDNOTES rons(Fig.1Aandfig.S1).Inadditiontomediat- (Fig.1B)(16,17),weexpressedChR2–enhanced
1. IPCC,ClimateChange2013:ThePhysicalScienceBasis. ing orienting responses (7), the SC contributes yellow fluorescent protein (EYFP) in specific
ContributionofWorkingGroupItotheFifthAssessmentReport to avoidance anddefense-like behaviors (8–11). neuronalsubtypesintheSC(Fig.1Candfig.S1)
oftheIntergovernmentalPanelonClimateChange,
andoptogeneticallyelicitedspikesinacuteslices
T.F.Stocker,D.Qin,G.-K.Plattner,M.Tignor,S.K.Allen,
J.Boschung,A.Nauels,Y.Xia,V.Bex,P.M.Midgley,Eds. (Fig.1Dandfig.S1).ActivationofSCPV+neurons,
(CambridgeUniv.Press,Cambridge,2013). 1StateKeyLaboratoryofBrainandCognitiveSciences, butnotSST+orVIP+neurons,triggeredimpulsive
2. G.A.Meehl,H.Teng,J.M.Arblaster,NatureClim.Change4, InstituteofBiophysics,ChineseAcademyofSciences, escaping(1.18T0.09s)followedbylong-lasting
898–902(2014). Beijing100101,China.2UniversityofChineseAcademyof freezing(46.4T2.8s)(Fig.1,EtoG;fig.S1;and
3. G.A.Meehl,A.Hu,J.M.Arblaster,J.Fasullo,K.E.Trenberth, Sciences,Beijing100049,China.
J.Clim.26,7298–7310(2013). *Correspondingauthor.E-mail:[email protected] movie S2). To avoid activation of PV+ retinal
1472 26JUNE2015(cid:127)VOL348ISSUE6242 sciencemag.org SCIENCE
Possible artifacts of data biases in the recent global surface warming
hiatus
Thomas R. Karl et al.
Science 348, 1469 (2015);
DOI: 10.1126/science.aaa5632
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EDITORIAL
The beyond-two-degree inferno
I
n the history of humankind, there is a dearth of ex- States has pledged reductions of 26 to 28% below 2005
amples of global threats so far-reaching in their im- levels by 2025, with California independently choosing
pact, so dire in their consequences, and considered to match the EU’s more ambitious goal. All eyes are on
so likely to occur that they have engaged all nations China and India, two of the largest total emitters of CO,
2
in risk mitigation. But now with climate change, we both of which have yet to submit their proposed INDCs
face a slowly escalating but long-enduring global in advance of COP21. Unfortunately, Piyush Goyal, In-
threat to food supplies, health, ecosystem services, dia’s Minister of State for Power, Coal, and New and
and the general viability of the planet to support a Renewable Energy, intends to double his nation’s coal
Marcia McNutt
population of more than 7 production by the year 2019
Editor-in-Chief
billion people. The project- to meet domestic energy re- 5
Science Journals 1
ed costs of addressing the quirements. China appears 0
2
problem grow with every to be taking the opposite 3,
year that we delay confront- track, recognizing its vul- y
ing it. In recognition of the nerability to climate change ul
shared risks we face and the and investing heavily in re- n J
collective action that will be newable energy.* Like Cali- o
necessary, an international fornia, China is betting that g
r
o
meeting of stakeholders good environmental policy g.
will convene in Paris next will make for good fiscal pol- a
m
week (www.commonfuture- icy by being in the vanguard e
paris2015.org), ahead of of the clean energy economy. c
n
the United Nations Climate I applaud the forthright e
ci
Change Conference (COP21) climate statement of Pope s
in December, to discuss Francis, currently our most w.
w
solutions for both climate visible champion for miti- w
mitigation and adaptation. gating climate change, and m
The time for debate has lament the vacuum in politi- o
r
ended. Action is urgently cal leadership in the United d f
needed. The Paris-based In- States. This is not the time to e
d
ternational Energy Agency “where [would]…Dante…place wait for political champions oa
recently announced that to emerge. Just as California nl
all of us who are borrowing w
current commitments to cut has decided to go it alone,
o
CO2 emissions [known as against this Earth…?” every sector (transportation, D
Intended Nationally Deter- manufacturing, agriculture,
BIS mined Contributions (IN- construction, etc.) and every
R
O DCs)] from the world’s nations are insufficient to avoid person need to do whatever is possible to reduce carbon
NI/C warming the entire planet by an average of more than pollution by conserving energy, adopting alternative en-
N
O VA 2°C above the preindustrial level. This is a target viewed ergy technologies, investing in research, and capturing
AN BERT awse tchaen bpoeurhnadpasr ya dbaepttw aenedn mcloimrea etex trweamrme winagr mtoin wg hthicaht COI2n a Dt athnete s’so Iunrfceer.n o, he describes the nine circles of Hell,
GI
© will be very disruptive to society and the ecosystems on each dedicated to different sorts of sinners, with the out-
SET) which we depend (see Gattuso et al. on p. 45). To set ermost being occupied by those who didn’t know any bet-
N
HY; (I more aggressive targets, developed nations need to re- ter, and the innermost reserved for the most treacherous
AP duce their per-capita fossil fuel emissions even further, offenders. I wonder where in the nine circles Dante would
R
OG and by doing so, create roadmaps for developing nations place all of us who are borrowing against this Earth in
HOT to leapfrog technologies by installing low-CO–emit- the name of economic growth, accumulating an environ-
ND P ting energy infrastructure rather than coal-fired2 power mental debt by burning fossil fuels, the consequences of
A
NTL plants as they expand their energy capacity. which will be left for our children and grandchildren to
STACEY PE moTsht ea gEgurreospsievaen I UNnDiCon t a(rEgUet) fios rl eraeddiuncgt itohne: wa acyu tw oitfh 4 t0h%e bcoenars?e qLueet’ns caecst onfo twh,e t boe syaovned t-htwe no-edxetg greenee irnafteironnos. from the
HT) below 1990 levels of CO2 emissions by 2030. The United – Marcia McNutt
G
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OS: (T *www.bbc.com/news/science-environment-33040965. 10.1126/science.aac8698
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Published by AAAS

EDITORIAL
Climate warning, 50 years later
L
ong before geophysicist Michael Mann’s hockey- tive to take action on climate change for the sake of
stick graph became the icon for anthropogenic the most disadvantaged members of society, who have
global warming, the U.S. President’s Science Ad- done the least to cause the problem. His message res-
visory Committee [now known as the President’s onates far beyond those of Catholic faith. Laudato Si
Council of Advisors on Science and Technology joins statements from many other religious leaders, in-
(PCAST)] cautioned President Lyndon B. Johnson cluding those of Buddhist, Muslim, Jewish, and other
that the continued release of CO to the atmo- Christian faiths.*
2
sphere from burning fossil fuels would “almost certainly The private sector is also stepping up its responsibility.
Marcia McNutt 5
cause significant changes” and “could be deleterious from This past summer, in the ramp-up to the Paris Conference 1
Editor-in-Chief 0
the point of view of human of the Parties to the United 2
beings.” The committee’s re- Nations Framework Conven- Science Journals 5,
2
port concluded that there tion on Climate Change, 12 r
could be “marked changes major corporations, includ- be
in climate, not controllable ing General Motors, Apple, m
e
through local or even nation- Google, Alcoa, and Bank of v
o
al efforts.” In recognition of America, pledged to invest N
the 50th anniversary of that more than $140 billion in ef- n
o
first official warning from forts to curtail CO2 emissions g
scientists to policy-makers, in the next 5 to 10 years. or
the American Association Although these an- g.
a
for the Advancement of Sci- nouncements from diverse m
ence (AAAS), the Carnegie sectors are all hopeful signs e
c
Institution for Science, the of a growing awareness of n
e
American Meteorological climate-change risk and the ci
s
Society, and the Linden Trust need to take action, some w.
for Conservation sponsored “…policy-makers should be leaders are instead distract- w
a 1-day climate symposium ing scientists from the im- w
on 29 October. sending thank-you notes— portant work at hand. Last m
o
Fifty years ago, the prob- not subpoenas—to express their month, the U.S. National r
lems of global warming Oceanic and Atmospheric d f
gratitude to scientists…” e
seemed distant and highly Administration (NOAA) d
a
uncertain. Today, we are al- received a subpoena from o
ready experiencing impacts from climate change. In the Lamar Smith (R–TX), chairman of the Committee on wnl
face of mounting urgency, there are signs of hope, though. Science, Space, and Technology in the House of Rep- o
D
Within the past few weeks, 10 oil producers, represent- resentatives, for all documents and communications
ing 20% of global production, have pledged to reduce among and between NOAA employees that refer to
greenhouse gas emissions by curbing the flaring of natu- various global temperature data sets. Ranking member
O
HOT ral gas and investing in carbon capture and storage. The Eddie Bernice Johnson (D–TX) labeled the subpoena “a
P
CK best part of this announcement is the acknowledgment fishing expeditionӠ triggered by a NOAA paper pub-
O
M/IST by energy giants BP, Pemex, Statoil, Saudi Aramco, Total, lished earlier this year in Science, “Possible artifacts of
KI Royal Dutch Shell, BG Group, Eni, Reliance Industries, data biases in the recent global surface warming hia-
A
HH and Repsol that climate change is a serious problem and tus.”‡ Senator Edward Markey (D–MA) summed up his
SET) that energy companies need to be part of the solution. opinion at the 50th anniversary event when he sug-
N
HY; (I Unfortunately, the proposed steps are inadequate contri- gested that policy-makers should be sending thank-you
AP butions toward meeting the goal of keeping the increase notes—not subpoenas—to express their gratitude to
R
OG in average global temperature to below 2°C, a target that scientists for sounding the alarm on the perils of green-
HOT would avoid the worst impacts from warming. house gas emissions. The senator’s remarks remind us
P
ND Another beacon of hope is the leadership being taken that we scientists should thank the many leaders who
A
NTL by faith-based groups. Pope Francis has done perhaps promote action on climate change.
CEY PE the most to raise world awareness of the moral impera- – Marcia McNutt
STA
GHT) *www.interfaithpowerandlight.org/resources/religious-statements-on-climate-change/. †http://democrats.science.house.gov/
OS: (RI sNiOteAsA/d%em20oScurabtpso.secniean.pcdef..h ‡oTu. sRe. .Kgaorvl/ eftil aesl./, SRcaineknicneg 3%4280, 1M4e6m9 b(2e0r%152).0Johnson%20Letter%20to%20Chairman%20Smith%20on%20 10.1126/science.aad7927
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Published by AAAS