Clmt vrblty nclds ll th vrtns n th clmt tht lst lngr thn ndvdl wthr vnts, whrs th trm clmt chng nly rfrs t ths vrtns tht prsst fr lngr prd f tm, typclly dcds r mr. Clmt chng my rfr t ny tm n rth's hstry, bt th trm s nw cmmnly sd t dscrb cntmprry clmt chng, ftn pplrly rfrrd t s glbl wrmng. Snc th ndstrl Rvltn, th clmt hs ncrsngly bn ffctd by hmn ctvts.
Th clmt systm rcvs nrly ll f ts nrgy frm th sn nd rdts nrgy t tr spc. Th blnc f ncmng nd tgng nrgy nd th pssg f th nrgy thrgh th clmt systm s rth's nrgy bdgt. Whn th ncmng nrgy s grtr thn th tgng nrgy, rth's nrgy bdgt s pstv nd th clmt systm s wrmng. f mr nrgy gs t, th nrgy bdgt s ngtv nd rth xprncs clng.
Th nrgy mvng thrgh rth's clmt systm fnds xprssn n wthr, vryng n ggrphc scls nd tm. Lng-trm vrgs nd vrblty f wthr n rgn cnsttt th rgn's clmt. Sch chngs cn b th rslt f "ntrnl vrblty", whn ntrl prcsss nhrnt t th vrs prts f th clmt systm ltr th dstrbtn f nrgy. xmpls ncld vrblty n cn bsns sch s th Pcfc dcdl sclltn nd tlntc mltdcdl sclltn. Clmt vrblty cn ls rslt frm xtrnl frcng, whn vnts tsd f th clmt systm's cmpnnts prdc chngs wthn th systm. xmpls ncld chngs n slr tpt nd vlcnsm.
Clmt vrblty hs cnsqncs fr s lvl chngs, plnt lf, nd mss xtnctns; t ls ffcts hmn scts.