row ing ▁trees . ▁He ▁calculated ▁that ▁it ▁would ▁take ▁a ▁tr ill ion ▁trees ▁to ▁remove ▁all ▁carbon ▁from ▁the ▁atmosphere . ▁In ▁a ▁ 2 0 1 4 ▁interview ▁he ▁said , ▁" What ▁I ' m ▁convinced ▁of ▁is ▁that ▁we ▁don ' t ▁understand ▁climate   ... ▁It ▁will ▁take ▁a ▁lot ▁of ▁very ▁hard ▁work ▁before ▁that ▁question ▁is ▁settled ." ▁ ▁D ys on ▁was ▁a ▁member ▁of ▁the ▁academic ▁advis ory ▁council ▁of ▁the ▁Global ▁W arm ing ▁Policy ▁Foundation , ▁a ▁climate ▁s cept ic ▁think ▁tank ▁cha ired ▁by ▁N ig el ▁Law son . ▁He ▁compared ▁belief ▁in ▁climate ▁change ▁to ▁religion . ▁ ▁War fare ▁and ▁weapons ▁At ▁the ▁British ▁Bom ber ▁Command , ▁D ys on ▁and ▁colle agues ▁proposed ▁removing ▁two ▁gun ▁tur rets ▁from ▁the ▁R AF ▁Lanc aster ▁bom bers , ▁to ▁cut ▁the ▁cat ast roph ic ▁losses ▁due ▁to ▁German ▁f igh ters ▁in ▁the ▁Battle ▁of ▁Berlin . ▁A ▁Lanc aster ▁without ▁tur rets ▁could ▁fly ▁ ▁faster ▁and ▁be ▁much ▁more ▁man eu ver able . ▁ ▁On ▁hearing ▁the ▁news ▁of ▁the ▁bomb ing ▁of ▁H iro sh ima : ▁ ▁In ▁ 1 9 6 7 , ▁in ▁his ▁capacity ▁as ▁a ▁military ▁advis er , ▁D ys on ▁wrote ▁an ▁influ ential ▁paper ▁on ▁the ▁issue ▁of ▁possible ▁US ▁use ▁of ▁tact ical ▁nuclear ▁weapons ▁in ▁the ▁Vietnam ▁War . ▁When ▁a ▁general ▁said ▁in ▁a ▁meeting , ▁" I ▁think