Laser beam excursion through atmosphere above the water surface and the land is presented. The results show that the beam excursion curves of the two paths have similar outline and cycle,and are similar to those of the temperature except of their phase ahead of 0.17-0.21π. The amount of beam excursion through the land path hL in vertical direction in one cycle 24 hrs is greater than that of the water path hw, and hL/hW equals to 1.14-1.40.