A king tide is a non-scientific term used to describe the highest predicted high-tide and lowest low-tide events of the year. King tides occur during a perigean spring tide, which happens when the Moon is closest to Earth and aligned with the Sun during a full or new moon. These tides are naturally occurring, predictable events that happen three or four times a year. The predicted heights of a king tide can be further augmented by local weather patterns and ocean conditions.

King tides are important because they show what average water levels might look like in the future based on sea-level rise projections. As water levels rise along the coastline, high tides can extend further inland and lead to local flooding. This is of particular concern when a king tide occurs under storm conditions, causing extreme storm surges that can lead to significant damage to property and coastline.

King tides are not a scientific term, nor are they used in a scientific context. However, they are a way to communicate local sea level rise impacts over long time periods. Photographing very high tides is a way to raise awareness of potential sea level rise impacts and identify flood-prone locations. The increased understanding of how sea level rise will impact local resources is valuable information for community decision-makers.