Subject: Why glycerol reduces the amount of ice in cells during cryopreservation?

Glycerol is a cryoprotective when freezing  sperm cells in liquid 
nitrogen. 
Without the cryoprotection of glycerol, cell death might occur. 
However, if glycerol is present there is a reduction in the 
amount of ice formed at subzero tempatures.  I was wondering: 
What is it about glycerol that reduce the amount of ice during 
freezing?
 Also, glycerol also reduces the build up in salt concentration 
in the cell? Could you help describe How/Why glycerol reduces the 
solution effects (salt concentration)?

Re: Why glycerol reduces the amount of ice in cells during cryopreservation?