Recently, Zoran Kahrić held a lecture on the development of NASA’s ICESat-2 satellite and here’s one of the first pictures we are publishing (thanks to Mr Kahrić).
The picture shows Bikini Atoll. The right figure shows where the laser beams went. In the left picture is beam # 2 (right line in color image); the surface of the sea (with waves) and the deep bottom can be seen. Then the bottom is raised, comes above the sea and begins the lagoon, which is shallow and no waves. At the end of the beam comes a reef that goes down to the surface and starts high waves again.