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Die son is 'n vurige massa botsende deeltjies. Ons weet nog min oor wat dit is. Kan dit wees dat die sonstroom, soos ons weer, van die een uiterste na die ander wissel? Van warm tydsduur tot koue tydsduur en weer terug. Ek dink aardverwarming is die gevolg van groter hoeveelhede sonenergie wat vrygestel word van die son; daarom word dit warmer hier. Ek glo die vraag is by uitstek belangrik vir alle mense op die planeet Aarde; is die mensdom, naamlik ons verbruik van fossielbrandstowwe, die oorsaak van ons penarie?
Ons weet baie van die son. Dit is nie die hoofoorsaak van aardverwarming nie, want ons kan presies monitor hoeveel energie dit produseer. Die sonproduksie kan wel wissel, en ons moet nog meet hoe erg dit die klimaat beïnvloed.
Wat is dus die hoofoorsaak van aardverwarming?
Die hoofoorsaak van aardverwarming is emissies van C02 (koolstofdioksied) in die atmosfeer. C02 is reukloos, kleurloos en nie-giftig, maar dit is die hoofoorsaak van aardverwarming. C02 is 'n kweekhuisgas en kan ongeveer 20 jaar in ons atmosfeer bly.
C02 veroorsaak iets wat die kweekhuiseffek genoem word. Die kweekhuiseffek is die idee dat langgolfenergie wat bedoel is om terug te gaan na die ruimte, nie teruggaan na die ruimte nie, maar eerder deur kweekhuisgasse soos C02 gevang word. Dit veroorsaak dat baie hitte wat na die ruimte moet gaan, vasgevang word in die atmosfeer van die aarde, wat veroorsaak dat u temperatuur styg.
Is daar enige ander kweekhuisgasse?
Ander kweekhuisgasse bestaan wel; koolstofdioksied is net die belangrikste een wat die aardverwarming veroorsaak. Ander kweekhuisgasse sluit in waterdamp, metaan, lachgas en osoon.
Vind aardverwarming net op Aarde plaas?
Aardverwarming vind oral in die sonnestelsel plaas, planete soos venus het ook baie kweekgasse in hul atmosfeer, feitlik, slegs op venus se kweekhuisgasse word die planeet 465 grade celsius warm, wat verby die kookpunt van water is - 100 grade celsius.
Stem ek nie saam nie?
Ja, aangesien daar te min bewyse is om te bewys dat die son genoeg energie wissel om ons klimaat dramaties te verhoog, en ons het ook die effek van kweekhuisgasse in 'n planete-atmosfeer bewys.
'N Daaglikse e-pos met die beste van ons joernalistiek
Op 2 NOVEMBER het die Interregeringspaneel oor Klimaatsverandering (IPCC), wat die algemene wetenskaplike opinie verteenwoordig, gesê dat dit uiters waarskynlik is dat klimaatsverandering die produk van menslike aktiwiteit is. Dit is baie waarskynlik in IPCC dat praat beteken dat u 'n waarskynlikheid van meer as 95% het. Die eis vorm deel van sy vyfde beoordeling oor die stand van die wêreldklimaat. In sy eerste beoordeling, in 1990, het die IPCC gesê dat die waargenome toename [in lugtemperature] grootliks te wyte kan wees aan natuurlike wisselvalligheid. & Quot Waarom het klimaatwetenskaplikes soveel meer seker geword dat klimaatsverandering deur die mens gemaak is, nie natuurlik nie?
Baie faktore beïnvloed die klimaat, maar miskien is die belangrikste koolstofdioksied (CO₂). CO₂ absorbeer infrarooi hitte teen 'n konstante tempo en teen 'n hoër tempo as stikstof en suurstof - die hoofbestanddele van die atmosfeer - dus hoe meer CO₂ in die lug is, hoe meer sal die atmosfeer geneig wees om op te warm. Wetenskaplikes skryf klimaatsverandering toe aan menslike aktiwiteite, hoofsaaklik omdat mense verantwoordelik was vir groot toename in CO₂. Aan die begin van die industriële rewolusie, in ongeveer 1800, was daar 280 dele per miljoen (dpm) CO₂ in die atmosfeer. Dit was die grootste deel van die mensegeskiedenis. Hierdie jaar het die konsentrasies egter 400 ppm oorskry, die eerste keer dat dit 'n miljoen jaar bereik het.
Die grootste deel van die toename is veroorsaak deur mense wat fossielbrandstowwe verbrand. In die Verenigde State, byvoorbeeld, kom 38% van die CO₂ wat in 2012 geproduseer is, van die opwekking van elektrisiteit en 32% van die uitstoot van voertuie (die res kom van industriële prosesse, geboue en ander kleiner CO₂-produksie). Mense produseer ook CO₂ as hulle woude kap vir landbougrond en weiding. Maar die tempo waarteen CO₂ hitte absorbeer - wat akkuraat in laboratoriums vasgestel is - verklaar nie al die toename in wêreldtemperature nie. As die CO₂-konsentrasie van 1800 vlakke sou verdubbel, sou die wêreldtemperature ongeveer 1 ° C styg. Maar daar is baie ander invloede op die klimaat.
Stygende CO₂-vlakke beïnvloed direk ander verskynsels, soos wolke, wat die toename in temperature versterk of soms verminder. Die byvoeging van roet en ander aërosols (fyn deeltjies wat in die lug hang) dra by tot of trek die effek van CO₂ af. As gevolg hiervan sal die aarde se temperatuur in die praktyk meer as 1 ° C opwarm vir elke verdubbeling van CO₂-konsentrasies. Daaroor is alle klimaatwetenskaplikes dit eens. Hoeveel te meer is daar egter 'n saak van wetenskaplike geskil. In die praktyk was die toename in globale oppervlaktemperature kleiner as wat die rekenaarmodelle van klimaat voorspel het. Maar wat nie meer ernstig betwis word nie, is dat mense die belangrikste agente vir klimaatsverandering is.
Is ons so seker dat aardverwarming die gevolg is van die feit dat mense fossielbrandstowwe verbrand? - Sterrekunde
Ek sal u eise evalueer.
Eerstens was u nie spesifiek met betrekking tot die werklike blog waarna u verwys nie, dus sal ek moet raai op grond van u posisie.
Vir u eerste eis van
Die blog blyk hierdie te wees aangesien dit oor OLS praat. https://climateaudit.org/2019/10/17/. skatting / die referate wat navorsers OLS gebruik het, daarom word dit bespreek. Hy wys die foute in die navorsers se wiskunde en kom tot die gevolgtrekking hieronder. Terloops, die blog is geskryf deur Nicholas Lewis, 'n wiskundige en klimaatwetenskaplike.
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Vir u tweede eis
Sy standpunt was dat die wiskunde wat in die vraestel gebruik word, die resultate lewer. Dus, die gevolgtrekkings van die vraestelle is gebaseer op die wiskunde. Die plek wat gebruik word, is nie relevant nie, aangesien dieselfde wiskunde deur die hele vraestel gebruik is.
Die manier waarop klimaatsoudit sy skakels opbou, maak dit moeilik om spesifiek te wees oor watter artikels verwys is
hier is die teks van die artikel wat ek gekritiseer het.
Een van die kenmerkende bevindings van IPCC AR5 WG2 was dat klimaatsverandering reeds 'n negatiewe uitwerking op oesopbrengste gehad het, veral koring en mielies. Hierdie bevindings is prominent in die WG2-opsomming vir beleidsmakers en is in die persdekking van WG2 genoem. Die onderwerp van oesopbrengste is 'n spesialiteit van WG2-medevoorsitter Christopher Field. Field se gereelde medeskrywer, David Lobell, was 'n hoofskrywer van die hoofstuk oor voedsel (hoofstuk 7), wat op sy beurt weer 'n reeks Lobell-artikels aangehaal het, veral Lobell et al (Science 2011, Climate Trends). en globale gewasproduksie sedert 1980, pdf), wat 'n statistiese ontleding was van oesopbrengste van 1980 tot 2008 (of tot 2002 in sommige ontledings) vir vier groot gewasse (koring, mielies, rys, soja) in 185 lande.
In die periode 1980-2008 het die oesopbrengs en die temperatuur positiewe neigings (ongeag die pouse in die 21ste eeu). Omdat albei reekse positiewe neigings het, is daar dus 'n positiewe korrelasie tussen oesopbrengste en temperature vir die oorgrote meerderheid oesland-kombinasies.
Aangesien albei reekse aan die toeneem is, is dit 'n baie geldige vraag om te wonder wie Lobell en mede-outeurs hul negatiewe impak bereik het deur bloot elementêre statistiese metodes toe te pas op jaarlikse data oor opbrengste, temperatuur en neerslag. Ek kyk na hierdie vraag in die boodskap van vandag.
In 2011 het ek die data vir Lobell et al 2011 verkry van hoofskrywer Lobell (wat destyds onderneem het om beide data en kode aanlyn te plaas, en dit lyk nie of dit gedoen is nie.) Ek het Lobell gevra om kode te argiveer, want dit was nie Dit is nie heeltemal duidelik wat hy gedoen het nie. Lobell het die temperatuur- en neerslagdata van UDel en CRU versamel. (Vir laasgenoemde gebruik Lobell die CRU TS-gegewens wat deur Harry Readme bekend gemaak is.) In die onderstaande figuur het ek Lobell se opbrengs- en temperatuurgegewens vir die China-koringkombinasie (albei gestandaardiseer tot SD-eenhede) geteken, soos 'n voorbeeld van albei reekse wat opgaan.
Lobell het die opbrengs (eintlik die logopbrengst) teruggesak teen die tyd-, temperatuur- en neerslagveranderlikes en die prosedure soos volg beskryf:
Die omskakeling van hierdie klimaatneigings in potensiële opbrengste-gevolge, vereis modelle van opbrengsrespons. Ons het regressie-ontledings van historiese data gebruik om die opbrengste van die vorige opbrengs in verband te bring met die weer. Al die modelle wat hieruit voortspruit, bevat T en P, hul vierkante, landspesifieke afsnitte om rekening te hou met ruimtelike variasies in gewasbestuur en grondkwaliteit, en landspesifieke tydtendense om opbrengsgroei as gevolg van tegnologiese winste te verreken (6).
Dit lyk asof die neerslag- en kwadratiese terme die regressie nie baie beïnvloed nie, dit wil sê die belangrikste effekte word deur die model waarin die opbrengs teen die tyd en die temperatuur teruggesak word, soos volg gelewer:
Met behulp van konvensionele regressie-nomenklatuur word die regressiekoëffisiënt b gegee deur die formule
waar die X-matriks van onafhanklike veranderlikes as Normaliseer die data vir u gemak (en is dus nie relevant tot die punt waarna ek werk nie). X ^ T y is eenvoudig die vektor van korrelasies tussen opbrengs en tyd (die genormaliseerde tendens) en temperatuur. (X ^ T * X) is niks anders nie as die korrelasiematriks tussen jaar en temperatuur, d.w.s. die off-diagonale element r is die temperatuurstendens (genormaliseerde eenhede) soos volg: Die berekening van die OLS-regressiekoëffisiënte gebruik die inverse van hierdie matriks, Die negatiewe term in die off-diagonaal beteken dat die OLS-koëffisiënt vir die regressie van opbrengs op tyd en temperatuur bereken word as 'n funksie van die korrelasie tussen opbrengs en temperatuur, die tendens in opbrengs, die tendens in temperatuur soos volg: b_temperatuur = 1 / (1-r ^ 2) (-r * trend_yield + cor_yield_temp) Met ander woorde, as die korrelasie tussen opbrengs en temperatuur minder is as die produk van die tendens in opbrengste en tendens in temperatuur (albei genormaliseer), dan is die regressiekoëffisiënt negatief. Dit het niks met opbrengste of temperature te doen nie, maar is 'n triviale eienskap van die matriksalgebra. Jammer oor die gebrek aan duidelikheid. Ek waardeer u poging om die artikel te probeer vind en burgerlike en metodes gebaseer te bespreek. Ek sal kyk na die artikel wat u gevind het en 'n antwoord gee as ek die treffer deurgelees het. Die keuse van regressiemetode in die klimaatveld is moeilik, en die subtiliteite van die regte keuse as u 'n outokorrelatiewe jaarreeks gebruik, is heeltemal korrek vir debat. Ek staan by my antwoord op bogenoemde artikel. Ek het dit gekies deur te googling & quot Steve mainctyre blog & quot om 'n ewekansige bladsy te kry en kies toe die eerste artikel wat 'n beweerde probleem met statistiese analise behandel. Ek het ook opgemerk dat Mcintyre afgelei het dat dit korrek was om uit 'n studie oor China te veralgemeen om die effek van aardverwarming op wêreldvlak aan te dui. Dit is 'n fundamentele fout. soos ek al voorheen gesê het, is dit goed om te sien dat iemand op hierdie draad die stof probeer hanteer. in u plasings. In werklikheid is daar glad nie veel van die inhoud nie. Het u iets of nie konstruktief te sê oor die probleme met die gebruik van OLS-regressie op jaarlikse tydreeksdata nie, maar ten minste een van die terme word omskep in 'n natuurlike log in vergelyking met die gebruik van logistieke regressie en detail met die kwessies van outomaties korrelasie. Ek het die artikel van Nick Lewis in McIntyre se Climate-ouditblog bekyk. Dit is van baie hoër gehalte as wat Mcintyre eintlik geskryf het. Lewis wys gewoonlik dat vierkantige regressie die a-term onder sekere omstandighede kan skat. Dit is 'n nuttige herinnering dat statistiese metodes onverwagte metingsfoute met sekere soorte data kan benadeel. Lewis is reg as hy beweer dat die statistiese teorie en kennis op die gebied van klimaatsverandering swak gebruik word. Sy eie kennis van statistiese metodes wat in die artikel getoon word, is egter beperk. Met klimaat het ons te make met 'n baie komplekse tydreeks van inligting waar die tydreeks van data nie slegs uit gestandaardiseerde en goed beheerde versameling is nie. Oor die tydreeks is data-beramings gemaak van beskikbare data, stelselmatige foute as gevolg van swak metingsentrums, wat handtekeningpatrone van foute en regstelling bekendstel. Daarbenewens is die wêreldklimaat beïnvloed deur 'n baie komplekse stelsel van faktore, waarvan sommige gedurende die hele tydreeks (wentelbaan van die son) gewissel het en ander wat verby is, maar uiters reaktief (die suurstof in die atmosfeer en die gepaardgaande verandering in plantegroei en spesies) Die toepassing van immer ontwikkelende berekenings- en statistiese metodes is 'n uitdaging. Daar moet baie verder gaan as wat Lewis aanvoer. Kwessies oor die meting en toepaslike analise van outokorrelasie en outo-regressiewe reekse met gemengde seisoenale en onderbroke effekte is ontwikkel op grond van die werk van Box en Jenkins en die identifisering van onderbroke tye-reekse met wisselende effekvlakke deur Campbell en Stanley en analise met behulp van spelteorie , Montecarlo-analise om 'n paar te noem, moet almal inlig wat die standaard onbevooroordeelde analise van goud is, Die rol van die Lewis-artikel in die McIntyre-blog is om saadjies van twyfel te saai oor resultate wat nie pas by 'n politieke oortuiging nie. Dit is om kennis te ondermyn eerder as om kennis te ontwikkel, soos die tabakbedryf se pogings om bande tussen rook en kanker te ondermyn. Ek sou graag wou sien dat meer statistieke verbeterde metodes ontwikkel, Lewis het potensiaal, maar 'n lang pad. Om afgelei te word deur by te dra tot McIntyre se blog, toon 'n gebrek aan oordeel. Kommentaar 101 tot 150 uit 872: Reaksie: Dankie vir die vriendelike kommentaar. Klimaatsensitiwiteit is in wese die verandering in temperatuur as gevolg van 'n verandering in die energiebalans van die planeet. Om klimaatsensitiwiteit te bereken, moet u dus uitvind hoeveel wêreldtemperature in die verlede verander het en die veranderinge in die destydse energiebalans van die planeet. As ons dus rekords kan verkry wat temperatuur gee (bv. Uit yskerne) en dit kan koppel aan rekords wat veranderings in sonaktiwiteit, atmosferiese samestelling en vulkaniese aktiwiteit gee, is dit moontlik om die klimaatsensitiwiteit empiries te bereken. Klimaatsensitiwiteit is ongeveer 3 grade warm vir 'n verdubbeling van CO2. 'N Meer tegnies korrekte definisie is 3 grade opwarming vir 'n stralingskrag van 2,7 watt per vierkante meter (wat die stralingskrag van 'n verdubbeling van CO2 is). As u dus wil kyk na die energiebalans van die planeet gedurende die afgelope tyd, moet u ander veranderlikes insluit wat die energiebalans van die planeet beïnvloed. Ons kom spesifiek agter dat die son minder helder is as u verder in die verlede gaan. U moet dus die gesamentlike effek van 'n dowwer son met hoër CO2 in die afgelope tyd oorweeg. As ons dit doen, vind ons 'n noue korrelasie tussen die netto stralingskrag en klimaat. Werkgroep III van die IPCC se vierde beoordelingsverslag het gefokus op die versagting van klimaatsverandering, en 'n groot deel van die verslag het gefokus op die ekonomiese gevolge van die versagtende pogings. Die belangrikste bevinding van die verslag is soos volg. 'Onder- en onder-na-onder-studies dui aan dat daar 'n aansienlike ekonomiese potensiaal is vir die versagting van wêreldwye broeikasgasvrystellings gedurende die komende dekades, wat die geprojekteerde groei van die wêreldvrystelling kan kompenseer of die uitstoot onder die huidige vlakke kan verminder (baie ooreenstemming, baie bewyse) ). " Die verslag het bevind dat stabilisering tussen 445 en 535 dpm CO2-ekwivalent (350-440 dpm CO2) sal die gemiddelde jaarlikse wêreldwye BBP-groeikoers met minder as 0,12% vertraag. Verder is hierdie vertraagde BBP-groeikoers in vergelyking met die onrealistiese scenario soos gewoonlik (BAU) waar klimaatsverandering geen impak op die ekonomie het nie. Teen 2030 het die IPCC bevind dat die globale BBP met altesaam nie meer as 3% sou daal in vergelyking met die onrealistiese BAU-scenario, afhangend van die omvang van die vermindering van die emissies. Die verslag het ook bevind dat voordele vir die gesondheid as gevolg van verminderde lugbesoedeling as gevolg van aksies om KHG-uitstoot te verminder, aansienlik kan wees en 'n aansienlike fraksie van die verminderingskoste kan vergoed. Enkele ander belangrike bevindings: "Energie-doeltreffendheidsopsies vir nuwe en bestaande geboue kan CO verminder2 emissies met netto ekonomiese voordeel. ' "Bosverwante versagtingsaktiwiteite kan die vrystelling van bronne aansienlik verminder en die CO verhoog2 verwydering deur wasbakke teen lae koste " "Beleide wat 'n reële of implisiete prys van koolstof bied, kan aansporings skep vir produsente en verbruikers om aansienlik in lae-KHG-produkte, -tegnologieë en -prosesse te belê. Sulke beleide kan ekonomiese instrumente, owerheidsfinansiering en regulering insluit." Kortom, daar is talle geleenthede om kweekhuisgasvrystellings teen lae koste te verminder, waarvan sommige 'n netto ekonomiese wins tot gevolg het. Oor die algemeen kan emissies verminder word teen 'n koste wat die wêreldekonomie nie verlam nie. Boonop sal hierdie vermindering van die uitstoot 'n beduidende positiewe ekonomiese impak hê deur die aardverwarming te vertraag. Ons het die nodige tegnologie. Die netto koste om dit te implementeer, sal nie verlammend wees nie. Die vraag bly staan: het ons die wil om die moeite en aanvanklike belegging aan te wend om die probleem op te los? Laas op 15 November 2010 deur dana1981 opgedateer. Om klimaatsverandering te bekamp, moet die lande van die wêreld dit hul hoogste prioriteit stel om die verbranding van fossielbrandstowwe binne die volgende 20 jaar heeltemal te vervang. As regerings fossielbrandstowwe teen 2040 nie heeltemal uitskakel nie, is die samelewing gedoem, sê Jeff Nesbit, skrywer van Dit is die manier waarop die wêreld eindig. Die soort apokaliptiese retoriek 'kos ons triljoene, maak die armes seer en slaag nie daarin om die planeet reg te stel nie', sê Bjorn Lomborg, die skrywer van Vals alarm. Is fossielbrandstowwe 'n dreigende bedreiging vir die menslike lewe, of is pogings om dit uit te skakel, vernietigender? Dit was die onderwerp van 'n aanlyn Soho Forum-debat in Oxford-styl wat op Sondag 18 Oktober 2020 aangebied is. Nesbit, wat die uitvoerende direkteur van Climate Nexus is, het ten gunste van die volledige uitskakeling van fossielbrandstowwe oor 20 jaar aangevoer. Hy het opgetree teen Lomborg, wat die president van die Kopenhagen-konsensussentrum is. Die debat is gemodereer deur Gene Epstein, direkteur van Soho Forum. Vertel deur Nick Gillespie, geredigeer deur Ian Keyser, intro deur John Osterhoudt Foto's: Gina M Randazzo / ZUMA Press / Newscom SEBASTIAN SILVA / EFE / Newscom imageBROKER / Jim West / Newscom Stefan Boness / Ipon / SIPA / Newscom. Redakteur se opmerking: Ons nooi kommentaar uit en vra dat dit burgerlik en onderwerp is. Ons aanvaar geen verantwoordelikheid vir kommentaar wat deur die lesers wat dit plaas, besit word nie. Opmerkings verteenwoordig nie die sienings van Reason.com of Reason Foundation nie. Ons behou die reg voor om te eniger tyd enige opmerking uit te vee. Meld misbruik aan. & # 8220 & # 8230 As regerings fossielbrandstowwe teen 2040 nie heeltemal uitskakel nie, is die samelewing gedoem, sê Jeff Nesbit. & # 8221 As hy nie kernkrag ondersteun nie, weet ons dat hy nie ernstig is nie. Tensy hy van Beijing of New Dehli teruggevlieg het om in hierdie debat te wees, weet ons dat hy nie ernstig is nie. "Reg en verkeerd" is redelik skerp, maar dit vang nie die volle diepte van antagonisme tussen die politieke stamme van die land nie. Verlede jaar het Nathan Kalmoe, politieke wetenskaplike van die Louisiana-staatsuniversiteit, opgemerk dat Google werk maklik en Google betaal my elke uur en elke week net $ 5 000 tot $ 8 000 vir die aanlyn werk van die huis af. Ek is 'n universiteitstudent en werk my deeltyds net 2 tot 3 uur per dag maklik van die huis af. Aop Nou kan elkeen ekstra kontant verdien vir die aanlyn-tuisstelsel en 'n goeie lewe maak deur net hierdie webwerf oop te maak en die instruksies op hierdie bladsy te volg ... Besoek hier Ja. Ons het nou kernenergietegnologie. Ons hoef nie dekades te wag totdat dit wyd beskikbaar is nie, veral as ons ontslae raak van die stremmende regeringsregulasies wat die tyd wat dit neem om 'n kernkragaanleg te bou, verdriedubbel. Die tegnologie van vandag is baie beter as dié van Tsjernobil. Die afval van & # 8220hernubare & # 8221 energiebronne soos sonpanele sal ook baie groter wees as wat deur kernkragaanlegte gegenereer word. Ek hou op om by die winkelrit te werk en verdien nou $ 65-85 per uur. Hoe? Ek werk aanlyn! My werk het my nie presies gelukkig gemaak nie, dus besluit ek om na 4 jaar 'n kans te waag om iets nuuts te doen, maar dit was so moeilik om my dagtaak op te hou, maar nou kon ek nie gelukkiger wees nie, dus probeer ek dit gebruik. Dit is duidelik dat Nesbit 'n fokken idioot is. As regerings teen 2040 nie fossielbrandstowwe heeltemal uitskakel nie, is die samelewing gedoem, sê Jeff Nesbit, skrywer van This Is the Way the World Ends. Ek wonder hoeveel eksemplare sy boek in China en Indië verkoop het? Dink jy dat hy weet dat dit net 'n stomme koffietafelboeke vir ryk wit mense is, of dink jy dat hy sy somers deurbring om dit op die straathoek in Beijing en Bangalore uit te deel? Ek vermoed laasgenoemde. * gluur na leë koffiebeker * Moet ons onsself in die kop skiet voordat ons onvermydelik aan ouderdom of siekte sterf? Hoe ver is die ouderdom en siekte gevorderd? Voorspelling: ons sal nog lank daarna aardgas gebruik. My gunsteling groep aller tye = Rush LOL. Spoeg amper my kos uit & # 8230 Moet ons oordeelsdagprofete laat besluit hoe ons ons lewe lei? Geen. Die probleem met valse digotomieë is dat dit nie vals is nie. Om die een of ander rede het 'n groot aantal van my mede-libertarisse (en medekapitaliste), wat twyfelagtig is of regverdig minagtend is met alle ander progressiewe aansprake, progressiewe snert geïnternaliseer oor hoe die enigste oplossings vir klimaatsverandering outoritêr en sosialisties is. Ek glo dit is die rede waarom hulle daarop aandring dat daar nie 'n probleem is nie. Ongeag, ek het nog nooit 'n situasie gesien waar die beste oplossing vir enigiets outoritêr en sosialisties was nie en dat die aardverwarming geen uitsondering is nie. Musk verkoop elektriese motors oor die vuis aan gretige kopers. Hy belowe nou om binne drie jaar 'n elektriese motor te koop wat minder as $ 25,000 kos. Dit gaan meestal oor verbeterings in die voorsieningsketting en toenemende skaal in hul batteryproduksie. Wie is daar wat albei die Green New Deal ondersteun en teen Musk se projeksies sou wed? Dink iemand dat Tesla (of sy mededingers) nog beter werk sou gedoen het as die regering oor 'n tydperk van vier jaar $ 2 triljoen belê het? Dit sou nie Musk se prestasie of die werklike wêreldprestasie van Tesla se mededingers verhoog het nie. Dit sou net 'n berg Solyndra & # 8217s geskep het vir Tesla om mee te ding. Dit kan veroorsaak het dat suksesvolle maatskappye soos Tesla misluk het. Aardgas is nog 'n voorbeeld van iets wat kweekhuisgasvlakke laat daal. Aardgas stel ongeveer 40% minder C02 in die atmosfeer vry om dieselfde hoeveelheid energie as steenkool te skep. Aardgas het nie steenkool vervang as gevolg van regulasie nie. Aardgas sou steenkool verdring het, selfs daarsonder. Die gebruik van aardgas in die plek van steenkool is nog altyd aangedryf deur die onderliggende markkragte. Aardgas is volop beskikbaar. Dit is minder arbeidsintensief om uit die grond te kom, en dit kos minder om dit by wyse van 'n pypleiding te vervoer as steenkool by spoorweë. Besef mense nie dat C02-emissies sedert 15 jaar gelede in die Verenigde State gedaal het nie, en dat dit grotendeels toe te skryf is aan die hidrobreking en die gebruik van natuurlike gas? Om die verbranding van natuurlike gas te verbied, is die verbod op 'n belangrike deel van die oplossing en 'n oplossing wat bydra tot die lewensstandaard van mense deur hulle in reële terme dieselfde hoeveelheid energie te gee vir minder geld. Intussen het ons nie eens die olifant in die kamer aangespreek nie & # 8211 openbare mening. Die vernietiging van alle fossielbrandstowwe sal so 'n vernietigende impak op die ekonomie hê, en die Amerikaanse volk sal sekerlik die eerste keer die party stem wat hul ekonomiese vernietiging buite werking stel. Dit het al voorheen in ander wêrelddele gebeur, veral Australië. Toe die Eerste Minister 'n koolstofbelasting inbring en boonop ander belasting, lyk dit na 'n revolusionêre en miskien selfs 'n gewilde idee, totdat die rekeninge verskyn. Australiërs was so kwaad oor die koste, dat hulle die eerste minister en haar party se regering met die eerste keer uit die Australiese parlement geslinger het. Geen oplossing kan slaag as dit nie gebaseer is op die grondbeginsels van die mark nie. Dit is soos om 'n vliegtuig te probeer ontwerp sonder om fisika in ag te neem. Dit maak nie saak hoe sleg ons wil hê dit moet vlieg of hoeveel ons glo nie. Dit maak nie saak of u van ysbere hou of nie daarvoor omgee nie. Die feit is dat as die verbod op die gebruik van fossielbrandstowwe nie op die grondbeginsels van die mark gebaseer is nie, dit sal misluk. Die goeie nuus is dat die mark vol oplossings is. En ek beskou die feit dat die gebruik van die dwangmag van die regering om Amerikaanse oplossings aan hierdie verbruikers toe te dien (oor hul besware en teen hul wil) ook geen goeie nuus sal wees nie. Wat 'n aaklige wêreld sou dit wees as outoritêre regering die wettige oplossing vir ons probleme sou wees. Aangesien die wêreld op die klimaatsgesprekke in Parys afgesien word, weet ons een ding vir seker en 'n sterk wêreldwye ooreenkoms moet getrou bly aan die wetenskap as ons die ergste gevolge van klimaatsverandering gaan voorkom terwyl ons diegene bestuur wat ons nie kan vermy nie. WWF verstaan die noodsaaklike belang van die kombinasie van voorpuntwetenskap met bewaringsbeplanning, -beleid en -praktyk, en werk saam met die Center for Climate Systems Research aan die Columbia University & rsquos Earth Institute om 'n nuwe benadering te skep om klimaatsinligting in die bewaringswerk ter plaatse in te sluit. Die ADVANCE (Adaptation for Development Conservation) -vennootskap sal beter begrip bewerkstellig van hoe die gevolge van klimaatsverandering mense en die natuur beïnvloed, en sal WWF help om ons huidige bewaringstrategieë te ontwikkel en nuwe oplossings aan te neem om 'n veiliger en gesonder planeet vir die toekoms te verseker geslagte. Ons is opgewonde oor waarheen ADVANCE ons sal neem, en hoe dit ons kollektiewe projekte vir bewaring, ontwikkeling en ramprisikovermindering sal help. Daar is reeds werk in Myanmar en die vennootskap het toekomstige projekte in Colombia, Bhutan en Tanzanië geïdentifiseer. WWF & rsquos Carter Roberts, links, en The Earth Institute & rsquos Jeffrey Sachs het op COP21 in Parys 'n ooreenkoms onderteken om 'n vennootskap tussen die twee organisasies te stig om klimaatnavorsing in bewaringspogings op te neem. Van die klimaatsgesprekke in Parys, tot ons wêreldwye ADVANCE-projekwebwerwe en daarbuite, is wetenskap van belang wanneer dit gaan om die bestuur van klimaatsverandering. Om ons werk saam te begin, het ons & rsquove bekende klimaatwetenskaplikes van ons vennote by die Centre for Climate Systems Research gevra om hul gedagtes te deel oor enkele van ons mees aktuele en dringende klimaatvrae: Sal biodiversiteit veilig wees as ons die opwarming van die aarde tot 2 ° C beperk? Tot dusver het die planeet sedert die voor-industriële tyd met ongeveer 1 & C opgewarm. Selfs met hierdie opwarmingspeil het wetenskaplikes al baie impak op spesies en ekostelsels aangeteken. Hierdie waargenome veranderinge sluit in verskuiwings in blomdatums van blomplant en tydsberekening van voortplanting, migrasie en winterslaap van diere. Hierdie tipe veranderinge sal meer voorkom namate die planeet aanhou warm word. Ten slotte is dit belangrik om daarop te let dat die doel van die klimaatonderhandelinge in Parys is om die gemiddelde wêreldwye jaarlikse temperatuurstyging te beperk tot 2 ° C bo die pre-industriële toestande. Al bereik ons hierdie doel, sal sommige dele van die planeet groter hoeveelhede opwarming ervaar as ander, veral aan die pole. Dit beteken dat sommige spesies blootgestel sal word aan gemiddelde jaarlikse temperatuurstygings wat baie groter is as 2 & degC, benewens veranderinge in die uiterste weer, verskuiwende seisoene, stygende seevlakke en suur oseane. Alhoewel sommige spesies daarby kan baat, sal hierdie veranderinge die verskuiwing van reekse vir baie soorte en moontlik selfs uitsterwing tot gevolg hê. Aangesien veranderinge in die klimaat die beskikbaarheid van voedselbronne sal beïnvloed, sal sommige spesies 'n afname in getalle ervaar, selfs al is hulle in staat om veranderinge in temperature en neerslae te weerstaan. Met inagneming van die somber klimaatvoorspellings, het ons al by die & lsquotipping point & rsquo geslaag? Op plaaslike skale sal spesifieke liggings hoër vlakke van opwarming, droogtes of swaarder stortreën hê wat plaaslike ekosisteme buite hul huidige toestand kan stoot. Some regions with degraded habitats, sensitive ecosystems, and low carrying capacity are likely to be very close to or have already surpassed their tipping points. However, understanding how the ecological systems have changed so far and identifying regional climate changes and impacts will help guide conservationists on how to increase resilience of these systems. Because it is not possible to know exactly where a tipping point may be, a risk averse approach argues for reducing emissions quickly to dramatically to lessen the risk of climate and ecological surprises. If we stop burning fossil fuels altogether today how long would it take for the climate to stabilize? Given this time lag, we also need to remember that even after temperatures stabilize, other systems such as oceans, ice sheets and biomes will continue to change far into the future. Even under low emissions scenarios, the Intergovernmental Panel on Climate Change suggests that climate would not &lsquostabilize&rsquo until hundreds or even thousands of years from now. A changing climate system affects biodiversity. We can and must slow the rate of global warming, but even the most aggressive efforts to limit greenhouse gas emissions will not stop change for a very long time to come, well beyond our own lifetimes. Why are some countries more vulnerable to climate change than others and which countries will be impacted the most? How can smallholder farmers in the developing world start to adapt to changing climate conditions without the resources that large-scale farmers have in the developed world? How is science improving climate projections? Do we know enough to act now? After decades of advances in scientific understanding and computational power, today&rsquos climate models are able to simulate many of the large-scale climate features that impact local climate, including high-pressure systems, mid-latitude storm tracks, and the jet stream. Projections of many important climate changes, such as the amount of warming and sea level rise are robust. As climate models continue to advance, they will tackle finer-resolution processes like what will happen to sea breezes and local storms. But we cannot wait for models to improve before taking action. We must make decisions today with the information we already have. Answers provided by: The issue can be overwhelming. The science is complicated. Predictions about the fate of the planet carry endless caveats and asterisks. So we’ve put together a list of quick answers to often-asked questions about climate change. This should give you a running start on understanding the problem. As of early 2017, the Earth had warmed by roughly 2 degrees Fahrenheit, or more than 1 degree Celsius, since 1880, when records began at a global scale. That figure includes the surface of the ocean. The warming is greater over land, and greater still in the Arctic and parts of Antarctica. The number may sound low. We experience much larger temperature swings in our day-to-day lives from weather systems and from the changing of seasons. But when you average across the entire planet and over months or years, the temperature differences get far smaller – the variation at the surface of the Earth from one year to the next is measured in fractions of a degree. So a rise of 2 degrees Fahrenheit since the 19th century is actually high. The substantial warming that has already occurred explains why much of the world’s land ice is starting to melt and the oceans are rising at an accelerating pace. The heat accumulating in the Earth because of human emissions is roughly equal to the heat that would be released by 400,000 Hiroshima atomic bombs exploding across the planet every day. Scientists believe most and probably all of the warming since 1950 was caused by the human release of greenhouse gases. If emissions continue unchecked, they say the global warming could ultimately exceed 8 degrees Fahrenheit, which would transform the planet and undermine its capacity to support a large human population. The risks are much greater over the long run than over the next few decades, but the emissions that create those risks are happening now. This means the current generation of people is dooming future generations to a more difficult future. Over the coming 25 or 30 years, scientists say, the climate is likely to resemble that of today, although gradually getting warmer, with more of the extreme heat waves that can kill vulnerable people. Rainfall will be heavier in many parts of the world, but the periods between rains will most likely grow hotter and drier. The number of hurricanes and typhoons may actually fall, but the ones that do occur will draw energy from a hotter ocean surface, and therefore may be more intense. Coastal flooding will grow more frequent and damaging, as is already happening. Longer term, if emissions continue to rise unchecked, the risks are profound. Scientists fear climate effects so severe that they might destabilize governments, produce waves of refugees, precipitate the sixth mass extinction of plants and animals in the Earth’s history, and melt the polar ice caps, causing the seas to rise high enough to flood most of the world’s coastal cities. All of this could take hundreds or even thousands of years to play out, but experts cannot rule out abrupt changes, such as a collapse of agriculture, that would throw civilization into chaos much sooner. Bolder efforts to limit emissions would reduce these risks, or at least slow the effects, but it is already too late to eliminate the risks entirely. You can reduce your own carbon footprint in lots of simple ways, and most of them will save you money. You can plug leaks in your home insulation to save power, install a smart thermostat, switch to more efficient light bulbs, turn off the lights in any room where you are not using them, drive fewer miles by consolidating trips or taking public transit, waste less food and eat less meat. Perhaps the biggest single thing individuals can do on their own is to take fewer airplane trips just one or two fewer plane rides per year can save as much in emissions as all the other actions combined. If you want to be at the cutting edge, you can look at buying an electric or hybrid car, putting solar panels on your roof, or both. If you want to offset your emissions, you can buy certificates, with the money going to projects that protect forests, capture greenhouse gases and so forth. Some airlines sell these to offset emissions from their flights . You can also buy offset certificates in a private marketplace, from companies such as TerraPass some people even give these as holiday gifts. In states that allow you to choose your own electricity supplier, you can often elect to buy green electricity you pay slightly more, and the money goes into a fund that helps finance projects like wind farms. Leading companies are also starting to demand clean energy for their operations. You can pay attention to company policies, patronize the leaders, and let the others know you expect them to do better. In the end, though, experts do not believe the needed transformation in the energy system can happen without strong state and national policies. So speaking up and exercising your rights as a citizen matters as much as anything else you can do. In the best case that scientists can imagine, several things happen: Earth turns out to be less sensitive to greenhouse gases than currently believed plants and animals manage to adapt to the changes that have already become inevitable human society develops much greater political will to bring emissions under control and major technological breakthroughs occur that help society to limit emissions and to adjust to climate change. Some technological breakthroughs are already making cleaner energy more attractive. In the United States, for instance, coal has been losing out to natural gas as a power source, as new drilling technology has made gas more abundant and cheaper for a given amount of power, gas cuts emissions in half. In addition, the cost of wind and solar power has declined so much that they are now the cheapest power source in a few places, even without subsidies. Unfortunately, scientists and energy experts say the odds of all these things breaking our way are not very high. The Earth could just as easily turn out to be more sensitive to greenhouse gases as less. Global warming seems to be causing chaos in parts of the natural world already, and that seems likely to get worse, not better. So in the view of the experts, simply banking on rosy assumptions without any real plan would be dangerous. They believe the only way to limit the risks is to limit emissions. Agriculture of all types produces greenhouse gases that warm the planet, but meat production is especially harmful &mdash and beef is the most environmentally damaging form of meat. Some methods of cattle production demand a lot of land, contributing to destruction of forests the trees are typically burned, releasing carbon dioxide into the atmosphere. Other methods require huge amounts of water and fertilizer to grow food for the cows. The cows themselves produce emissions of methane, a potent greenhouse gas that causes short-term warming. Meat consumption is rising worldwide as the population grows, and as economic development makes people richer and better able to afford meat. This trend is worrisome. Studies have found that if the whole world were to start eating beef at the rate Americans eat it, produced by the methods typically used in the United States, that alone might erase any chance of staying below an internationally agreed-upon limit on global warming. Pork production creates somewhat lower emissions than beef production, and chicken lower still. So reducing your meat consumption, or switching from beef and pork to chicken in your diet, are moves in the right direction. Of course, as with any kind of behavioral change meant to benefit the climate, this will only make a difference if lots of other people do it, too, reducing the overall demand for meat products. That is actually hard to say, which is one reason scientists are urging that emissions be cut they want to limit the possibility of the worst case coming to pass. Perhaps the greatest fear is a collapse of food production, accompanied by escalating prices and mass starvation. It is unclear how likely this would be, since farmers are able to adjust their crops and farming techniques, to a degree, to adapt to climatic changes. But we have already seen heat waves contribute to broad crop failures. A decade ago, a big run-up in grain prices precipitated food riots around the world and led to the collapse of at least one government, in Haiti. Another possibility would be a disintegration of the polar ice sheets, leading to fast-rising seas that would force people to abandon many of the world’s great cities and would lead to the loss of trillions of dollars worth of property and other assets. In places like Florida and Virginia, towns are already starting to have trouble with coastal flooding. Scientists also worry about other wild-card events. Will the Asian monsoons become less reliable, for instance? Billions of people depend on the monsoons to provide water for crops, so any disruptions could be catastrophic. Another possibility is a large-scale breakdown of the circulation patterns in the ocean, which could potentially lead to sudden, radical climate shifts across entire continents. As more companies, governments and researchers devote themselves to the problem, the chances of big technological advances are improving. But even many experts who are optimistic about technological solutions warn that current efforts are not enough. For instance, spending on basic energy research is only a quarter to a third of the level that several in-depth reports have recommended. And public spending on agricultural research has stagnated even though climate change poses growing risks to the food supply. People like Bill Gates have argued that crossing our fingers and hoping for technological miracles is not a strategy &mdash we have to spend the money that would make these things more likely to happen. The ocean is rising at a rate of about a foot per century. That causes severe effects on coastlines, forcing governments and property owners to spend tens of billions of dollars fighting erosion. But if that rate continued, it would probably be manageable, experts say. The risk is that the rate will accelerate markedly. If emissions continue unchecked, then the temperature at the Earth’s surface could soon resemble a past epoch called the Pliocene, when a great deal of ice melted and the ocean rose by something like 80 feet compared to today. A recent study found that burning all the fossil fuels in the ground would fully melt the polar ice sheets, raising the sea level by more than 160 feet over an unknown period. Many coastal experts believe that even if emissions stopped tomorrow, 15 or 20 feet of sea-level rise is already inevitable. The crucial issue is probably not how much the oceans are going to rise, but how fast. And on that point, scientists are pretty much flying blind. Their best information comes from studying the Earth’s history, and it suggests that the rate can on occasion hit a foot per decade, which can probably be thought of as the worst case. Even if the rise is much slower, many of the world’s great cities will flood eventually. Studies suggest that big cuts in emissions could slow the rise, buying crucial time for society to adapt to an altered coastline. The idea that Earth is sensitive to greenhouse gases is confirmed by many lines of scientific evidence. For instance, the basic physics suggesting that an increase of carbon dioxide traps more heat was discovered in the 19th century, and has been verified in thousands of laboratory experiments. Climate science does contain uncertainties, of course. The biggest is the degree to which global warming sets off feedback loops, such as a melting of sea ice that will darken the surface and cause more heat to be absorbed, melting more ice, and so forth. It is not clear exactly how much the feedbacks will intensify the warming some of them could even partly offset it. This uncertainty means that computer forecasts can give only a range of future climate possibilities, not absolute predictions. But even if those computer forecasts did not exist, a huge amount of evidence suggests that scientists have the basic story right. The most important evidence comes from the study of past climate conditions, a field known as paleoclimate research. The amount of carbon dioxide in the air has fluctuated naturally in the past, and every time it rises, the Earth warms up, ice melts and the ocean rises. A hundred miles inland from today’s East Coast of the United States, seashells can be dug from ancient beaches that are three million years old, a blink of an eye in geologic time. These past conditions are not a perfect guide to the future, because humans are pumping carbon dioxide into the air far faster than nature has ever done. But they show it would be foolish to assume that modern society is somehow immune to large-scale, threatening changes. Most of the attacks on climate science are coming from libertarians and other political conservatives who do not like the policies that have been proposed to fight global warming. Instead of negotiating over those policies and trying to make them more subject to free-market principles, they have taken the approach of blocking them by trying to undermine the science. This ideological position has been propped up by money from fossil-fuel interests, which have paid to create organizations, fund conferences and the like. The scientific arguments made by these groups usually involve cherry-picking data, such as focusing on short-term blips in the temperature record or in sea ice, while ignoring the long-term trends. The most extreme version of climate denialism is to claim that scientists are engaged in a worldwide hoax to fool the public so that the government can gain greater control over people’s lives. As the arguments have become more strained, many oil and coal companies have begun to distance themselves publicly from climate denialism, but some are still helping to finance the campaigns of politicians who espouse such views. Scientists have published strong evidence that the warming climate is making heat waves more frequent and intense. It is also causing heavier rainstorms, and coastal flooding is getting worse as the oceans rise because of human emissions. Global warming has intensified droughts in regions like the Middle East, and it may have strengthened a recent drought in California. In many other cases, though, the linkage to global warming for particular trends is uncertain or disputed. That is partly from a lack of good historical weather data, but it is also scientifically unclear how certain types of events may be influenced by the changing climate. Another factor: While the climate is changing, people’s perceptions may be changing faster. The Internet has made us all more aware of weather disasters in distant places. On social media, people have a tendency to attribute virtually any disaster to climate change, but in many cases there is little or no scientific support for doing so. Countries with huge, frozen hinterlands, including Canada and Russia, could see some economic benefits as global warming makes agriculture, mining and the like more possible in those places. It is perhaps no accident that the Russians have always been reluctant to make ambitious climate commitments, and President Vladimir V. Putin has publicly questioned the science of climate change. However, both of those countries could suffer enormous damage to their natural resources escalating fires in Russia are already killing millions of acres of forests per year. Moreover, some experts believe countries that view themselves as likely winners from global warming will come to see the matter differently once they are swamped by millions of refugees from less fortunate lands. Scientists have been warning since the 1980s that strong policies were needed to limit emissions. Those warnings were ignored, and greenhouse gases in the atmosphere were allowed to build up to potentially dangerous levels. So the hour is late. But after 20 years of largely fruitless diplomacy, the governments of the world are finally starting to take the problem seriously. A deal reached in Paris in late 2015 commits nearly every country to some kind of action. President Trump decided in 2017 to pull the United States out of that deal, saying it would unfairly burden American businesses. But other countries are promising to go forward with it anyway, and some states and cities have defied Mr. Trump by adopting more ambitious climate goals. Religious leaders like Pope Francis are speaking out. Low-emission technologies, such as electric cars, are improving. Leading corporations are making bold promises to switch to renewable power and stop forest destruction. What is still largely missing in all this are the voices of ordinary citizens. Because politicians have a hard time thinking beyond the next election, they tend to tackle hard problems only when the public rises up and demands it. The environmental pressures from global agriculture are enormous. Global demand for beef and for animal feed, for instance, has led farmers to cut down large swaths of the Amazon forest. Brazil adopted tough oversight and managed to cut deforestation in the Amazon by 80 percent in a decade. But the gains there are fragile, and severe problems continue in other parts of the world, such as aggressive forest clearing in Indonesia. Scores of companies and organizations, including major manufacturers of consumer products, signed a declaration in New York in 2014 pledging to cut deforestation in half by 2020, and to cut it out completely by 2030. The companies that signed the pact are now struggling to figure out how to deliver on that promise. Many forest experts consider meeting the pledge to be difficult, but possible. They say consumers must keep up the pressure on companies that use ingredients like palm oil in products ranging from soap to lipstick to ice cream. People can also help the cause by altering their diets to eat less meat, and particularly less beef. Many people imagine the ocean to be like a bathtub, where the water level is consistent all the way around. In fact, the sea is rather lumpy &mdash strong winds and other factors can cause water to pile up in some spots, and to be lower in others. Also, the huge ice sheets in Greenland and Antarctica exert a gravitational pull on the sea, drawing water toward them. As they melt, sea levels in their vicinity will fall as the water gets redistributed to distant areas. How the rising ocean affects particular parts of the world will therefore depend on which ice sheet melts fastest, how winds and currents shift, and other related factors. On top of all that, some coastal areas are sinking as the sea rises, so they get a double whammy. The greenhouse gases being released by human activity are often called “carbon emissions,” just for shorthand. That is because the two most important of the gases, carbon dioxide and methane, contain carbon. Many other gases also trap heat near the Earth’s surface, and many human activities cause the release of such gases to the atmosphere. Not all of these actually contain carbon, but they have all come to be referred to by the same shorthand. By far the biggest factor causing global warming is the burning of fossil fuels for electricity and transportation. That process takes carbon that has been underground for millions of years and moves it into the atmosphere, as carbon dioxide, where it will influence the climate for many centuries into the future. Methane is even more potent at trapping heat than carbon dioxide, but it breaks down more quickly in the air. Methane comes from swamps, from the decay of food in landfills, from cattle and dairy farming, and from leaks in natural gas wells and pipelines. While fossil-fuel emissions are the major issue, another major creator of emissions is the destruction of forests, particularly in the tropics. Billions of tons of carbon are stored in trees, and when forests are cleared, much of the vegetation is burned, sending that carbon into the air as carbon dioxide. When you hear about carbon taxes, carbon trading and so on, these are just shorthand descriptions of methods designed to limit greenhouse emissions or to make them more expensive so that people will be encouraged to conserve fuel. “In philosophy, there’s the technical term ‘moral status’ which means you have a reason for treating something a certain way,” says Dr Shepherd. So if a living being can feel pain or joy it’s deemed to have value and should be treated with respect. Humans are thought to have the highest level of moral status but some environmental activists disagree. “Some plants have a high status, for example, the rainforest or plants from which we get food. And many medicines come from plants. But do you keep plants alive just for human survival rather than in their own right? It depends on your value system,” he says. Trees are alive, an ecosystem in their own right and an important part of our environment. But, conflicts between trees and people often happen. This can be due to a tree’s natural growth endangering human life, such as an overgrown branch hanging over a pavement or playground. And conflict can result from human activities impacting on trees - such as that car crash we mentioned at the beginning. But trees, like humans, also have medics to look after them. It’s a tree surgeon’s job to maintain the health and welfare of trees. So humans help trees - the development of tree surgery indicates some people care about them a great deal. Many keen gardeners will tell you talking to their plants helps them grow. And even if it doesn’t, people enjoy growing them and having them in their homes and gardens. We get enormous pleasure from plant life. Do people in the developed world have the right to demand that people in the developing world don’t build over their natural environments? People are thought to be a higher evolved form of life than plants because we can experience and give great joy. We’re presumed to have a high degree of intelligence and sophistication and to make rational choices. Yet, some argue that humans aren’t always rational and can cause great suffering as well as joy. Whereas plants never set out to deliberately harm us - except in sci-fi novels such as ‘The Day Of the Triffids’ (by John Wyndham) when plants take over and kill people! Maybe the reason why this story is so popular is that it touches upon a deep fear that plants might one day fight back? “We assume humans are vastly more important than plants but when you start to think of why that is, you can get to some interesting places,” adds Dr Shepherd. “For some people, all life matters. That would be the argument from environmental philosophers. Some argue you shouldn’t mess with nature unless you have a very good reason, e.g. human life is at risk”. This morning in Sweden representatives from the Intergovernmental Panel on Climate Change presented a summary of the current state of scientific knowledge about climate change, a brief version of part of the IPCC’s upcoming full report. Most of the attention is being paid—and rightly so—to the things we know we know for sure: the temperature is rising, the sea level is, too. And we and our carbon emissions are largely to blame. The IPCC report speaks a language of certainties and uncertainties—what do we think we know? how certain are we about it? The headline news from this new IPCC report is that we’re overwhelmingly certain that people are causing climate change. But what are we less confident about? The short answer is: we’re less sure about what’s happening in places where there’s less data— whether because historically there’s been less funding for science there, as in places outside the northern hemisphere, or less human presence, as in Antarctica. This doesn’t undermine the IPCC’s claims: these sources of uncertainty were all taken into consideration when the IPCC said that we’re the dominant driver of climate change. Rather, they’re a reminder that though the science of climate change is settled, it isn’t complete. There’s a lot more work for scientists to do, and many open questions—some of them quite large. Answering these questions will do a great deal to help us answer the really important question: what’s next? So here, gleaned from the IPCC’s briefing, are some of the things we’re still trying to work out: What’s up with clouds? We’ve touched on this one before, but it’s just as true as ever: we don’t really know what’s going on with clouds. We know that they’re important in determining the “climate sensitivity,” the measure of how much warming you’d expect for a given increase in greenhouse gases. And they’re also obviously relevant to figuring out how the weather will be affected. But, as the IPCC says, trying to make clouds in a computer model is tricky. The southern hemisphere The bulk of long-term scientific research has been focused on the northern hemisphere, and those gaps in the observation grid mean that we know less about how things work down under. We’re not quite as sure how all the extra energy in the Earth’s atmosphere, trapped by greenhouse gases, is warming the air in the Southern Hemisphere. This isn’t to say it isn’t warming. The question is about how much warming we’re seeing at different altitudes. We’re also not quite sure how the rain has, or will, change. We know that over the northern hemisphere rainfall has been going up, but we’re not so sure what’s going on over the ocean or in the southern hemisphere. Changes in Antarctic ice The vast Antarctic glaciers are a focus of a lot of research, but we’re not really sure how they work. Scientists are trying to figure that out, because all of that ice could mean a lot of sea level rise. National Geographic says that if Antarctica and all the other ice melted we’d get something like 216 feet of sea level rise. (This is never going to happen, but it’s not fun to think about.) We also don’t know as much as we’d like about the gigantic floating sheets of ice that ring Antarctica. Scientists are having trouble understanding why they sometimes seem to be growing, and there’s a lot of uncertainty in our predictions of what will happen to them as the world continues to warm. Arctic permafrost bomb The Arctic reaches of Canada and Siberia and Scandinavia and other polar regions are full of permafrost—land that’s frozen year round. As the world gets warmer, it makes sense that this permafrost will start to thaw (and it has been). What people are really worried about is that, trapped within this frozen soil, there is whole lot of carbon in the form of decaying plant material known as peat. Peat likes to catch on fire. Peat also releases carbon dioxide and methane as it breaks down. So, there’s a big worry that if we keep thawing out the frozen peat, that there will be a big surge in greenhouse gases. But that’s exactly what it is—a worry. We’re not really sure how much extra greenhouse gases will be released from all this frozen land. A lot of it depends on how much we can limit global warming. The power of the sun Some people like to claim that changes in the amount of energy coming from the Sun are what’s actually causing climate change, and that greenhouse gas emissions aren’t to blame. If it’s all the Sun’s fault, then we’re off the hook. Those people are wrong. That being said, of course changes in the amount of energy coming from the Sun affect the climate. How this happens, though, is the question. Scientists think that there may be a connection between the 11-year solar cycle and medium-term changes in the climate, changes that happen from decade to decade. This matters because these decade-to-decade changes can stack on top of the long-term changes caused by anthropogenic climate change. The fate of the AMOC There’s a gigantic circulation system running all throughout the world’s oceans, linking them together, transporting nutrients and salt and heat between the Pacific and the Atlantic and the Indian and the others. The Atlantic Ocean branch of this system is called the Atlantic Meridional Overturning Circulation—meridional because it flows “along the meridian,” and overturning because, from north to south, it flows along the bottom of the ocean, and from south to north, it flows along the top. This circulation system is very important for keeping everything moving, and its behavior affects everything from the temperature in Europe to the strength of the monsoon in China. Scientists are worried that if climate change melts enough of the ice in Greenland and the rest of the Arctic that this circulation pattern could slow down, or even stop entirely. The IPCC says it’s “very unlikely” that the AMOC will stop in the next 100 years, but, after that, they’re not so sure. What’s the takeaway here? We’re already locked in to a certain amount of climate change, thanks to the greenhouse gases we’ve already let into the air. We know that the world is going to change, but in some cases we’re not quite so sure what exactly is going to happen. We know a lot about climate change—we know that it’s happening and that it’s our fault—but that doesn’t mean scientists can take a break. There’s still a lot of work to be done to understand how the planet’s going to react to these changes we’ve wrought.
Aanvaar u of aanvaar u nie dat gegewens uit een land China gerneraliseer kan word sonder verdere bewyse om die begrip van die effek van die aardverwarming op die opbrengs in te lig nie?
Ons is nog besig met die ontwikkeling en validering van wetenskaplike en wiskundige benaderings om ons kennis te sistematiseer en gevolgtrekkings te maak. Vir die hele stelsel is die wetenskap beslis nie besleg nie, maar die teorie van AGW is geïdentifiseer as 'n waarskynlike bedreiging vir die gesondheid van die wêreldklimaat en hier, omdat die effekstydperk beperk is, met toenemende datastelle met verbeterde betroubaarheid en 'n besliste tydperk van industrialisering is 'n vaste saak vir regstellende oorsake.
Natuurwetenskaplikes wat gewoond is aan die gebruik van eksperimente en beheerde omgewings, sukkel met die statistieke van onbeheerde natuurlike omgewing waar die beheer van veranderlikes onmoontlik is. Sommige kies om te sê dat dit nie wetenskap is nie, maar dit laat geen manier om belangrike kennisareas aan te spreek nie.
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Moet ons fossielbrandstowwe afskaf om aardverwarming te stop? 'N Soho Forum-debat
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Die bestuur van klimaatsverandering begin met die wetenskap
Die antwoord op hierdie vraag hang grootliks af van watter spesies of ekosisteme ons oorweeg. Sommige spesies en ekosisteme is meer sensitief vir verandering as ander. Volgens die Interregeringspaneel oor klimaatsverandering, sal 'n toename van 1-2 & degC 'n risiko inhou vir unieke en bedreigde stelsels. En wetenskaplikes het ook deur middel van modellering getoon dat die impak op biodiversiteit dekades lank na klimaatstabilisering kan voortduur.
'N Kantelpunt beteken 'n punt van terugkeer, waardeur die wêreldklimaat of 'n plaaslike ekosisteem buite die grense van die huidige toestand gedryf word. Sommige navorsers sê dat ons die kantelpunt vir wêreldwye ysplate oortref het en dat dit sal smelt teen snelhede wat katastrofiese veranderinge in die seevlak tot gevolg sal hê. Ander wetenskaplikes is nie so seker nie en glo dat as die nasies van die wêreld kan saamstem om hul uitstoot so gou as moontlik te beperk, kan die wêreldwye klimaatsisteem steeds met 'n beperkter impak behoue bly. Ongeag, die boodskap is duidelik dat aksies om ons uitstoot van kweekhuisgasse vandag te verminder, toekomstige bevolkings sal bevoordeel deur die ergste gevolge van klimaatsverandering te bewerkstellig.
Even if humans were to completely stop burning fossil fuels like oil, coal and natural gas, the Earth&rsquos atmosphere would continue to warm for at least decades and possibly centuries. This is because carbon dioxide, the major greenhouse gas, remains in the atmosphere for hundreds of years after it is released when we burn fossil fuels.
The amount of warming, rainfall patterns, sea level rise, storms and other changes in the climate vary across the earth. Local climate conditions, geography (e.g., low-lying coastal areas), exposure of people and infrastructure, sensitive ecosystems, and capacity to withstand risks and recover all vary from country to country. While all countries are vulnerable to climate change both directly (through climate changes within their borders) and indirectly (through climate changes in other countries that lead, for example, to increases in the price of food), some regions are more vulnerable than others. Small island nations and nations with large populations living in megadeltas (e.g., Bangladesh and much of Southeast Asia) are particularly vulnerable to sea level rise and coastal flooding. Those least developed countries in the subtropics and tropics that rely on highly variable precipitation for staple crops&mdashmany of which are in Africa&mdashare also highly vulnerable.
In many respects, smallholder farmers are at a disadvantage in the face of climate change. They may lack access to capital markets and agrotechnology. However, these farmers are often knowledgeable about traditional varieties of crops and crop management strategies that are more suitable for the projected conditions (e.g., rice varieties that are more tolerant to droughts). Some smallholder farmers may also have strong social support networks. Making sure these farmers have access to climate risk information at seasonal and longer time scales is a step towards leveling the playing field. This type of climate information can also assist government and aid agencies as they target suitable resources and build capacity to help farmers adapt.
Climate models are our best available tool for simulating the climate of the future. Climate models will continue to improve, but for many climate problems, we already have enough information to act. Many of the largest obstacles to mitigation and adaptation are not related to a lack of climate information but rather are related to existing systems and policies.
&bull Cynthia Rosenzweig, Senior Research Scientist, NASA Goddard Institute for Space Studies and Columbia University
&bull Radley Horton, Associate Research Scientist, Center for Climate Systems Research, The Earth Institute, Columbia University,
&bull Manishka De Mel, Staff Associate, Center for Climate Systems Research, The Earth Institute, Columbia University,
&bull Danielle Peters, Staff Associate, Center for Climate Systems Research, The Earth Institute, Columbia University
Short Answers to Hard Questions About Climate Change
So what makes us think we're more important than plants?
We Know Humans Are Causing Global Warming Here Are Some Things We’re Less Sure About
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