Land-Water Distribution and the Pear-Shape of the Earth

The orbital analysis of artificial Earth satellites have revealed the existence of a strong third harmonic in the gravitational potential of the Earth which gives its ‘pear-shape’ in the averaged meridional section. Various attempts to explain this pear-shape based on physical principles have proved to be inconclusive. In this study, a new approach based upon statistical correlation between variables has been advocated. It is shown that even though geoid highs and lows do not generally correspond to the locations of the continents and oceans, the average land-water distribution bears significant correlation with the geoid heights. Specifically, the distribution of water is directly correlated to the geoid heights whereas the distribution of land is inversely correlated with the latter. This analysis is consistent with the principle of mass loading and is also able to locate the ‘stem’ of the pear at the North pole. It is suggested that the correlation between land-water distribution and the pearshape of the Earth is causal rather than coincidental.