What is the difference between absolute sea level change and relative sea level change?

Absolute sea level change refers to changes in the height of the ocean's surface relative to the center of the Earth, measured globally using satellite altimetry. It reflects the actual increase or decrease in the volume of water in the oceans, influenced by factors such as melting ice sheets, thermal expansion, and changes in ocean circulation. In contrast, relative sea level change is the change in sea level experienced at a specific location, accounting for both the absolute change in the ocean's surface and the vertical movement of the land. Land movements can be caused by factors such as tectonic activity, subsidence, or glacial isostatic adjustment. Thus, relative sea level change can vary significantly from place to place, even if the global absolute sea level is rising.