Question: Global or eustatic sea level is different from local sea level because: Group of answer choices Eustatic sea level is measured relative to a fixed point on land, whereas local sea level is measured by sonar on board ocean going vessels. Local sea level is measured relative to a specific location on land and global sea-level is measured relative to the earth's center and averaged across the planet. Local sea level is the average of all local measurements and global sea level is the average of all global sea level measurements.