A tsunami warning is an alert issued to inform people about the potential for a tsunami, which is a series of large ocean waves typically caused by underwater earthquakes, volcanic eruptions, or landslides. These warnings are crucial for coastal communities, as tsunamis can cause significant destruction and loss of life. Warnings are issued by organizations like the National Oceanic and Atmospheric Administration (NOAA) in the United States. They use seismic data and ocean buoys to monitor conditions and determine if a tsunami is likely to occur. When a warning is issued, it is important for people in affected areas to evacuate to higher ground immediately.