Answer:
In fact, ice is slightly less reflective than water. The reflectivity is related to the refractive index (in a rather complicated way) and the refractive index of ice is 1.31 while the refractive index of water is 1.33. The slightly lower refractive index of ice will cause a slightly lower reflectivity. In both cases, the reflectivity is about 0.05 i.e. at an air/water or air/ice surface about 5% of the light is reflected.
Explanation:
