Climate science: how it matters for understanding forecasting, materials I’ve read or plan to read, sources of potential bias

As part of a re­view of fore­cast­ing, I’ve been look­ing at weather and cli­mate fore­cast­ing (I wrote one post on weather fore­cast­ing and an­other on the differ­ent time hori­zons for weather and cli­mate fore­cast­ing).

Cli­mate fore­cast­ing is turn­ing out to be a fairly tricky topic to look into, partly be­cause of the in­her­ent com­plex­ity of the task, and partly be­cause of the poli­ti­ciza­tion sur­round­ing An­thro­pogenic Global Warm­ing (AGW).

Due to the com­plex­ity and the po­ten­tial for bias, I de­cided to dis­close what ma­te­ri­als I’ve read and my po­ten­tial sources of bias.

Why am I look­ing at cli­mate fore­cast­ing?

Cli­mate fore­cast­ing, and the de­bate sur­round­ing what’ll hap­pen to the cli­mate and how hu­man choices to­day can shape it, is one of the biggest ex­am­ples of a long-range fore­cast­ing effort that has at­tracted wide­spread at­ten­tion, both in terms of the sci­ence and the policy and poli­ti­cal im­pli­ca­tions. Un­der­stand­ing how it was done can give in­sights into the abil­ity of hu­mans to make fore­casts about the long-run fu­ture (on the decadal or cen­ten­nial timescale) in the face of con­sid­er­able un­cer­tainty, and use those fore­casts to drive de­ci­sions to­day. This would be rele­vant for other long-range fore­cast­ing prob­lems, such as (pos­si­bly) friendly AI. Note though that my fo­cus isn’t driven by find­ing par­allels with any other spe­cific fore­cast­ing prob­lem, such as friendly AI.

The sorts of ques­tions I hope to an­swer by the end of this inquiry

The fol­low­ing are ques­tions to which I hope to state rel­a­tively clear an­swers by the end:

  • How good are we at cli­mate fore­cast­ing?

  • How good are we at know­ing how good we are at cli­mate fore­cast­ing? Are the fore­casts ap­pro­pri­ately cal­ibrated, or do they tend to be over­con­fi­dent or un­der­con­fi­dent?

  • Are cli­mate fore­cast­ers us­ing the best tools available to them from other do­mains (such as statis­tics, econo­met­rics, fore­cast­ing, weather fore­cast­ing)? Are they us­ing best prac­tices in their efforts?

  • What is the level of ev­i­dence re­gard­ing An­thro­pogenic Global Warm­ing (AGW) and to what ex­tent have the peo­ple gen­er­ally deferred to as ex­perts cor­rectly weighed the ev­i­dence?

The fol­low­ing are ques­tions to which I may not ob­tain clear an­swers, but I’ll be look­ing for and re­port­ing in­for­ma­tion on them be­cause they in­fluence the an­swers to the pre­ced­ing ques­tions:

  • Given that cli­mate fore­casts, and the AGW hy­poth­e­sis in par­tic­u­lar, have been con­sid­ered a ba­sis for sig­nifi­cant col­lec­tive ac­tion (such as re­strict­ing emis­sions, or sub­sidies to al­ter­na­tive en­ergy sources), there are ob­vi­ously big poli­ti­cal stakes in the out­come of the sci­ence. Oil and coal com­pa­nies, par­tic­u­larly if they don’t an­ti­ci­pate be­ing eas­ily able to di­ver­sify, stand to lose from policy mea­sures, while nu­clear, so­lar. and wind en­ergy com­pa­nies might gain. To what ex­tent have these vested in­ter­ests in­fluenced the sci­ence?

  • More gen­er­ally, to what ex­tent have peo­ple’s be­liefs about the pos­si­ble poli­ti­cal con­se­quences about spe­cific out­comes af­fected the sci­ence in ways that are not epistem­i­cally jus­tified? For in­stance, do peo­ple who are more risk-averse tend to ex­ag­ger­ate the harms, so that they can con­vince a less risk-averse pub­lic to take ac­tion? Do peo­ple who view re­stric­tions on car­bon diox­ide emis­sions as eco­nom­i­cally dis­as­trous tend to down­play the sci­en­tific ev­i­dence for AGW in or­der to min­i­mize the prob­a­bil­ity of emis­sions re­duc­tion leg­is­la­tion?

Sources

Courses or full-fledged reviews

Books about cli­mate change aimed at a pop­u­lar audience

  • Six De­grees: Our Fu­ture on a Hot­ter Planet by Mark Ly­nas (Ama­zon, Wikipe­dia)): I only read the chap­ters about warm­ing up to 3 de­grees Cel­sius. The fo­cus of my in­quiry is the cli­mate fore­cast­ing it­self, not so much the con­se­quences of it, but I did want to get a han­dle on what sorts of con­se­quences peo­ple ex­pect.

  • Com­ing Cli­mate Cri­sis? Con­sider the Past, Be­ware the Big Fix by Claire J. Park­in­son (Ama­zon): I have read Chap­ters 1 and 5 so far, and in­tend to read/​skim other chap­ters when writ­ing about rele­vant ma­te­rial.

Books about spe­cific con­tro­ver­sies sur­round­ing cli­mate change

    • The Hockey Stick Illu­sion: Cli­mate­gate and the Cor­rup­tion of Science by An­drew Mont­ford (Ama­zon, Wikipe­dia): I read al­most the whole book (skip­ping some pages of the last chap­ter). De­spite the sub­ti­tle, the book is not about Cli­mate­gate but rather about the de­bate sur­round­ing the hockey stick graph. The graph is ac­tu­ally quite periph­eral to the cen­tral de­bates of cli­mate sci­ence, but the de­bate sur­round­ing it pro­vides im­por­tant in­sight into the so­ciol­ogy of cli­mate sci­ence and the IPCC pro­cess.

    • The Cli­mate Files: The Bat­tle for the Truth about Global Warm­ing by Fred Pearce (Ama­zon): I read the whole book.

    Book chapters

    • Chap­ter 12 of Nate Silver’s The Sig­nal and the Noise. This chap­ter is about cli­mate sci­ence, and speci­fi­cally about an­thro­pogenic global warm­ing. The book also has a chap­ter on weather fore­cast­ing that I read and used in an ear­lier post.

    IPCC reports

    Blogs and websites

    I refer­ence here only the blogs and web­sites I’ve iden­ti­fied as places to check out, rather than ones where I chanced upon an iso­lated blog post by link-traips­ing or search­ing the web.

    • Skep­ti­cal Science (web­site, Wikipe­dia): Un­like what the name sug­gests, it is not run by global warm­ing skep­tics but rather by peo­ple who seek to de­bunk global warm­ing skep­ti­cism. I used this web­site mainly to un­der­stand both the stan­dard ar­gu­ments offered against the An­thro­pogenic Global Warm­ing (AGW) hy­poth­e­sis and the com­mon main­stream re­but­tals to these ar­gu­ments. I found it to be a rea­son­ably com­pre­hen­sive com­pendium of ar­gu­ments and re­but­tals.

    • Watts Up With That? (WUWT) (web­site, Wikipe­dia) run by An­thony Watts (Wikipe­dia): I used this web­site ex­ten­sively to un­der­stand non-main­stream and skep­ti­cal per­spec­tives on cli­mate sci­ence, as well as some as­pects of the source of ran­cor and skep­ti­cism ex­pressed by out­side-the-es­tab­lish­ment blog­gers. As a gen­eral rule, when­ever look­ing up a topic, I searched for it on WUWT. I found WUWT to have fairly thor­ough and com­pre­hen­sive cov­er­age and the in­di­vi­d­ual posts to be quite long and de­tailed, but not all posts should be treated as re­li­able or on par with a pub­lished ar­ti­cle. Each post should be eval­u­ated at the ob­ject level.

    • Cli­mate Au­dit (CA) (web­site, Wikipe­dia), run by Stephen McIn­tyre (Wikipe­dia): Although this too is la­beled a skep­tic site, it has much more limited scope. While WUWT cov­ers any and all cli­mate sci­ence-re­lated top­ics and fea­tures guest posts from all sorts of peo­ple, CA is more fo­cused on the mod­el­ing and statis­ti­cal meth­ods used in pa­pers. As the name sug­gests, the pur­pose is more like an au­di­tor than some­body at­tempt­ing to sell a com­pet­ing the­ory. I’ve used this to un­der­stand some of the con­tro­ver­sies sur­round­ing mea­sure­ment, and get a sense of the poli­tics and dy­nam­ics of dis­putes.

    • RealCli­mate (web­site, Wikipe­dia): This was the web’s first cli­mate blog. In fact, it has been de­scribed in The Cli­mate Files and The Hockey Stick Illu­sion as a way for cli­mate sci­en­tists to re­gain con­trol of the pub­lic de­bate in the face of all the In­ter­net dis­cus­sion among skep­tics cri­tiquing their pa­pers. That be­ing said, I didn’t find the posts there very use­ful for un­der­stand­ing the is­sues in­volved. Part of it might be the com­bat­ive tone used, part of it was the low fre­quency of post­ing, and part of it was the lack of math­e­mat­i­cal de­tail ac­com­pa­ny­ing many of the posts.

    • Ju­dith Curry’s blog (web­site, Wikipe­dia on Curry): Curry is an in­ter­est­ing peo­ple be­cause she iden­ti­fies as a main­stream sci­en­tist but also en­gages with, and highly re­spects, the work of skep­tic web­sites such as WUWT and CA.

    Papers

    I read many pa­pers from a di­verse ar­ray of sources. I ar­rived at most pa­pers ei­ther by click­ing links on one of the blogs or web­sites men­tioned above, or us­ing Google or Google Scholar searches for spe­cific top­ics. Any pa­per that I use as in­put to my opinion in a spe­cific post will be ex­plic­itly linked in that post.

      Po­ten­tial for bias and inaccuracy

      • My poli­ti­cal views lean liber­tar­ian, and al­though I don’t think this af­fects my view of the plau­si­bil­ity of cli­mate the­o­ries di­rectly, it does af­fect the in­tel­lec­tual en­vi­ron­ment I op­er­ate in (less defer­en­tial to the main­stream con­sen­sus). I don’t think this was an is­sue, since the list of sources I used were mostly de­rived us­ing Google Search and Wikipe­dia as start­ing points, rather than my liber­tar­ian friends. But it might have af­fected me. Some peo­ple have also ar­gued that since liber­tar­i­ans op­pose heavy-handed gov­ern­ment in­ter­ven­tion, they have an in­cen­tive to not be­lieve in an­thro­pogenic global warm­ing since it pre­sents an “in­con­ve­nient truth” for their po­si­tion.

      • I don’t know much about the sub­ject. The above read­ing list is hardly enough to train my­self in cli­mate sci­ence. How might my lack of knowl­edge bias me? It might make me too sen­si­tive to pre­sen­ta­tion. In par­tic­u­lar, this may lead me to take po­si­tions es­poused in skep­tic blogs such as WUWT and CA more se­ri­ously: the au­thors com­bine (what seems to be) a care­ful ex­am­i­na­tion of the data with a de­sire to get at the truth of what­ever em­piri­cal is­sue they are in­ves­ti­gat­ing, and they share in con­sid­er­able de­tail their thought pro­cess. In con­trast, the Real Cli­mate blog posts are more like an­nounce­ments than in­ves­ti­ga­tions I feel part of. But this does not mean that WUWT or CA is more re­li­able, of course: the cli­mate sci­en­tists blog­ging at Real Cli­mate are more busy writ­ing up stuff for pub­li­ca­tion than shar­ing it on blogs. Much as I might pre­fer the blog­ging cul­ture to the pa­per-writ­ing cul­ture, I should avoid us­ing this as an im­por­tant in­put in my eval­u­a­tion of the le­gi­t­i­macy of spe­cific sci­en­tific claims.

      Look­ing for suggestions

      As always, I’m happy to hear sug­ges­tions. In par­tic­u­lar, I am in­ter­ested in sug­ges­tions on these fronts:

      • Ad­di­tional sources I should re­fer to

      • Cau­tions or caveats for read­ing or in­ter­pret­ing the sources already on my list (or per­haps a sug­ges­tion to read some of the already listed sources more thor­oughly)

      • Other sources of bias I might have that I missed

      • Po­ten­tial ways to cor­rect for my bias