Converting Units of Solar Radiation

There have been many suggestions to include the formulas used to convert radiation from MJ / m2 and Watts /m2 to micromoles. For radiation data, both VEMAP and Hubbard Brook report total global radiation in MJ m-2 day-1. As PnET uses PAR (umoles m-2 sec-1), we have converted from one to the other using: 

       umoles   =    MJ     X   2.0513 umole    X           day
      --------    --------     --------------       ---------------------
       m2 sec      m2 day             MJ             seconds of daylight

For radiation reported in Watts, to convert Watts/m2 into MJ/m2: 

       MJ    =   (W/m2) (3.6 KJ/W)
      ----      -------------------
       m2               10^3


Return to download page

© 2001 Complex Systems Research Center