How do interpolation and extrapolation differ, which is more reliable

These 2 are techniques whereby an individual tries to analyze and observe additional data points or information that may not be recorded and or obvious. From a graph, usually linear.

Interpolation involves the individual to be aware of the pattern observed or relationship between the 2 variables and tries to obtain a value that is in between 2 recorded or defined data points.

Extrapolation involves the individual to estimate and imagine what the graph would appear as if further data was collected, based on the previous recordings. This can be found out due to the relationship between the 2 variables in the graph.

Thermohaline circulation and gyres