▁for ests . ▁He ▁believed ▁that ▁existing ▁simulation ▁models ▁of ▁climate ▁change ▁fail ▁to ▁account ▁for ▁some ▁important ▁factors , ▁and ▁that ▁the ▁results ▁thus ▁contain ▁too ▁great ▁a ▁margin ▁of ▁error ▁to ▁reli ably ▁predict ▁future ▁tr ends . ▁ ▁D ys on ' s ▁views ▁on ▁global ▁war ming ▁were ▁critic ized . ▁Cl imate ▁scient ist ▁James ▁Hans en ▁said ▁that ▁D ys on ▁" does n ' t ▁know ▁what ▁he ' s ▁talking ▁about   ... ▁If ▁he ' s ▁going ▁to ▁w ander ▁into ▁something ▁with ▁major ▁consequences ▁for ▁human ity ▁and ▁other ▁life ▁on ▁the ▁planet , ▁then ▁he ▁should ▁first ▁do ▁his ▁home work   – ▁which ▁he ▁obviously ▁has ▁not ▁done ▁on ▁global ▁war ming ." ▁D ys on ▁replied ▁that ▁"[ m ] y ▁ob jections ▁to ▁the ▁global ▁war ming ▁propag anda ▁are ▁not ▁so ▁much ▁over ▁the ▁technical ▁facts , ▁about ▁which ▁I ▁do ▁not ▁know ▁much , ▁but ▁it ' s ▁rather ▁against ▁the ▁way ▁those ▁people ▁behave ▁and ▁the ▁kind ▁of ▁int ol er ance ▁to ▁criticism ▁that ▁a ▁lot ▁of ▁them ▁have ." ▁ ▁D ys on ▁argued ▁that ▁political ▁efforts ▁to ▁reduce ▁the ▁causes ▁of ▁climate ▁change ▁dist ract ▁from ▁other ▁global ▁problems ▁that ▁should ▁take ▁priority . ▁ ▁Since ▁originally ▁taking ▁interest ▁in ▁climate ▁studies ▁in ▁the ▁ 1 9 7 0 s , ▁D ys on ▁suggested ▁that ▁carbon ▁dio x ide ▁levels ▁in ▁the ▁atmosphere ▁could ▁be ▁controlled ▁by ▁plant ing ▁fast - g