What is “corrected mean sea level” in tide predictions?

Corrected mean sea level in tide predictions refers specifically to the average sea level that has been adjusted to account for various influences that can cause fluctuations in sea height. Among the factors considered are atmospheric pressure and the effects of wind, both of which can significantly impact the actual sea level at a given moment.

In meteorological terms, low atmospheric pressure can result in higher sea levels (a phenomenon known as the inverse barometer effect), while high atmospheric pressure can lead to lower sea levels. Wind can also cause temporary increases or decreases in water levels, especially in coastal areas.

This corrected mean sea level provides a more accurate baseline for predicting tides, allowing mariners and scientists to understand and anticipate the natural changes in sea level that may occur due to these atmospheric conditions. This accuracy is crucial for navigation, coastal management, and various maritime activities, ensuring that tide predictions reflect real-world conditions as closely as possible.