As I was reviewing the data and papers
gathered together for the optical properties of water, I discovered
that the people who have reported the optical absorption of water fall
into two groups: those who actually do measurements and those who
compile all the currently available data and choose a reasonable set. In general,
the former group are compelled to do their measurements because they are
disappointed by the current status of compiled data. The discussion
section of these papers always makes it clear that their data is in
agreement with published work and yet slightly better.
Of course, the group that compiles existing data are then compelled
to create yet another compilation so that there will be a nice
accepted water spectrum.
All the data on this page is presented in terms of wavelength in
nanometers and the Beer's law absorption coefficient µa
that is presented in units of inverse centimeters.
If you are still not clear on where to look for the optical properties of
water then you should probably click here.