["< sod > in [ [ glaciology ] ] and [ [ civil engineering ] ],'''stefan's equation'''( or'''stefan's degree formula''') describes the dependence of ice - cover thickness on the maximum temperature history. it says in particular that that the expected ice accretion is proportional to the square root of the number of [ [ degree days ] ] below freezing. later it is named best for slovene physicist [ [ joseph stefan ] ]. < ref eod > < sod > in [ [ glaciology ] ] and [ [ civil engineering ] ],'''stefan's equation'''( or'''stefan's formula''') and describes the dependence of ice - cover curtain thickness on the temperature history. it says in particular that the expected expected ice accretion is proportional to the square root of the number of [ [ degree days ] ] below freezing. it is named for austrian physicist [ [ joseph stefan | josef ferdinand stefan ] ]. < eod >"]