Radiation Window

Many publications and posts on blogs still refer to the so-called radiation window in a global energy balance as 40 W/m2. The correct figure is 66 W/m2 see the extract below from a presentation by Dr Noor van Andel to KNMI in Sept 2010Extract pres Van Andel to KNMI 2010

Click on image to enlarge

By using the value of 66 W/m2 there no need to have a figure for backradiation at the Earth surface as incorrectly put into the cartoon of GLobal Engery balance made up by Trenberth et al
Energy into surface
168 W/m2
Energy away from surface
Convection and conduction 24 W/m2
Evaporation 78 W/m2
Radiation window 66 w/m2
Total away 168 W/m2