Waves are the motion of the water's surface, usually caused by the transfer of energy from wind. Wave energy causes the water to move in a circular motion. The height and length of these waves combined with the slope of the beach influence how high the water can reach up on the coast. Waves are an important component of the total water level, which is how high the water gets. Scientists in the USGS Coastal Change Hazards group use measurements of beach slope, along with wave height predictions from partners at the National Oceanic and Atmospheric Administration, to predict how high water will reach along our coastlines. These forecasts are available in the Total Water Level and Coastal Change Hazards forecast viewer.