Describe the difference between Isostatic and Eustatic sea level change?

Isostatic sea level change refers to a change in the level of the land relative to the sea, and it is a localised change. The two main causes are isostatic rebound - the slow rise of areas that were once covered by ice during the last ice age, as well as tectonic activity - a short term shift in the level of the level of the land due to seismic activity. Eustatic sea level change refers to the change in the level of the sea itself, with the effect of this being global. It can be caused by thermal expansion - water expanding as it gets warmer leading to it being a larger volume, or also as a result of the melting of ice caps causing more water to be stored as a liquid form the in ocean, rather than as solid form as ice on land.