It's more than a third. Roughly half the circle is water. It also contains all of Tibet, the Hindu Kush and the Southeast Asian rainforest (except New Guinea).

It's more than a third. Roughly half the circle is water. It also contains all of Tibet, the Hindu Kush and the Southeast Asian rainforest (except New Guinea). Furthermore it contains the highly mountainous islands of Japan, Taiwan, the Phillippines and Indonesia. Proclaiming that all or even most of this land is "habitable" is obviously silly if you just look at it: https://media.cntraveler.com/photos/593eedf1f2125a2b5b9ed24d/master/w_768,c_limit/map-reddit-cr.jpg https://media.cntraveler.com/photos/593eedf1f2125a2b5b9ed24d... Any glance at a map of population density will reveal that all of the highest density areas (pink) are within the circle: https://en.m.wikipedia.org/wiki/Population_density#/media/File%3AWorld_population_density_1994_-_with_equator.png https://en.m.wikipedia.org/wiki/Population_density#/media/Fi... This is definitely an interesting phenomenon and not just clickbait. The most likely explanation is that high rainfall in East Asia has allowed high-yield rice cultivation preceding the Green Revolution, allowing East Asia to support much higher population density in preindustrial times than any other region. Europe is too cold, Africa and West Asia too dry, and the Americas didn't have rice. (Although they did have the potato, but it didn't spread outside the Andes without European assistance.)