v ary ing ▁quantities ▁such ▁as ▁atmos pher ic ▁CO 2 ▁concentration , ▁carbon ▁budget , ▁and ▁ar ctic ▁sea ▁ice ▁volume . ▁ ▁Background ▁ ▁Haw kins ▁cred ited ▁a ▁" F rid ay ▁afternoon " ▁email ▁from ▁Norwegian ▁clim at ologist ▁Jan ▁F ug l est ved t ▁for ▁the ▁idea ▁of ▁converting ▁a ▁conventional ▁col oured ▁line ▁chart ▁into ▁a ▁spir al , ▁and ▁thank ed ▁F ug l est ved t ' s ▁wife , ▁Tar an ▁F æ hn , ▁for ▁having ▁suggested ▁it ▁to ▁F ug l est ved t . ▁F æ hn , ▁a ▁research er ▁for ▁Statistics ▁Norway ▁and ▁the ▁Os lo ▁Centre ▁for ▁Research ▁on ▁Environment ally ▁Friend ly ▁Energy , ▁had ▁suggested ▁that ▁connecting ▁December ▁to ▁the ▁following ▁January ▁would ▁show ▁temperature ▁evolution ▁in ▁a ▁more ▁dynamic ▁way . ▁En su ing ▁email ▁discuss ions ▁ref ined ▁the ▁design ▁of ▁the ▁climate ▁spir al , ▁which ▁Haw kins ▁published ▁on ▁Monday ▁ 9 ▁May ▁ 2 0 1 6 . ▁ ▁D iss em ination ▁Ex pect ing ▁" only ▁some ▁vague ▁interest ", ▁Haw kins ▁later ▁wrote ▁that ▁his ▁twe et ▁of ▁the ▁new ▁graph ic ▁had ▁been ▁viewed ▁ 3 . 4 ▁million ▁times ▁in ▁its ▁first ▁year . ▁The ▁twe et ed ▁graph ic ▁is ▁widely ▁described ▁as ▁having ▁gone ▁vir al . ▁Within ▁a ▁day , ▁Cl imate ▁Central ▁writer ▁Andrea ▁Thompson ▁remarked ▁in ▁The ▁Guardian ▁that ▁the ▁" met ap hor ic ▁spir al " ▁of ▁the