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Re: Strange "Energy" Units



W/m^2 is a conventional unit for *rate* of energy transfer. Of course
an orthodox physicist would not like even this, since the "per unit
area" is still tacit. Making the time element tacit offends my
sensibilities, but in a discussion where that is the only related
quantity arising (such as a discussion of the heat budget of Earth)
it is conventional to shorten the phrase further, to energy transfer.

If I can live with and understand "energy transfer" per se, anyone
ought to be able to do so. I think that, as a physicist, one is less
likely to become confused by this usage than is a non-physicist. (I
almost said "normal person"!)

I frequently tell my students that, for approximate purposes, they
should remember that the solar energy flux intercepted at Earth's
surface is a kilowatt per square meter. Of course there are several
qualifications that need to be made for more accurate work, but the
rough number is one they should always retain. The terminology is
imprecise, but that should not bother the good physics student. She
can figure out what is meant by looking at the units, as you did.

Leigh