Interestingly, if you take this method and require the base’s elevation to be somewhere at or above sea level, you get the height of the mountain as it would appear to a human viewer

I say interesting bc when we use this methodology, Denali in Alaska actually appears to be the largest. While its peak is only ~20k feet above seal level, its lowest base is 3k above sea level. Making it appear to be 17k feet tall. Meanwhile Everest is something like 29k and 14k, making it appear to be 15k feet tall, or about 2k feet shorter than Denali

This is sometimes mistaken for a mountain’s “prominence”, but that’s actually a different measurement