Updated arXiv articles

Three of my articles posted to arXiv.org have been updated:

• "Efficient statistical classification of satellite measurements" (arxiv:1202:2194v2)
• "Microwave emissivity of fresh water ice--Lake ice and Antarctic ice pack--Radiative transfer simulations versus satellite radiances" (arxiv:1202.4095v2)
•  "Sea Ice Brightness Temperature as a Function of Ice Thickness, Part II: Computed curves for thermodynamically modelled ice profiles" (arxiv:1202.6567v2)

Mostly it is fairly minor corrections, however for the first article I have added a whole new appendix on how one of the equations is derived.  When I first wrote the article, I had thought that the derivation was trivial enough that it could be omitted.  I now realize that this is somewhat presumptive and arrogant and that not everyone has the time or inclination to sit down trying to derive complex formulas.  In a piece of writing whose job it is to convey information, better to include too much than too little.