Approximately how much lower is the northern hemisphere's elevation compared to the mean planetary elevation?

Answer

4 to 5 km

The Martian dichotomy is characterized by the northern hemisphere, known as Vastitas Borealis, lying significantly lower, specifically between 4 and 5 kilometers below the average elevation of the planet.

Approximately how much lower is the northern hemisphere's elevation compared to the mean planetary elevation?
ancientMarsGeologyevidenceshoreline