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Low population, low flatlands or a hot or cold climate qualify as such.
Soil quality and climate are the main factors for such high population density. Central Mexico has a high altitude above sea level (around 2000 meters or 6500 ft), allowing a temperate climate unlike the scorching deserts to the north, or the suffocating tropical rain-forests to the south. Also, central Mexico's altitude is the result of strong volcanic activity, resulting in rich topsoil that allows higher agricultural yields and in turn, bigger populations.
injurious climate
New Mexico has an arid and semi-arid climate.
Mexico has almost every climate
The population of The Climate Group is 100.
Northern Mexico is part of the Sonoran and Chihuahuan deserts, so it has a dry, arid climate. The Mexican central plateau, where Mexico City and many other cities are located, has a temperate climate, such as San Francisco or Los Angeles in the United States. Southern Mexico has a more tropical climate, but as Mexico has a rugged topography, some parts of the south have a "mountain jungle" climate that is incredibly humid, but temperate.
Mexico's climate is in the 90's in the day, and drops as far as 30 degrees at nighttime in the dessert.
it poops in its pants
The population of State of Mexico is 15,175,862.
HSBC Mexico's population is 22,000.
It has milder climate and better soil for agriculture, in contrast to the suffocating deserts to the north and the tropical climate on the coasts. This in turns allows for more intensive agriculture and a higher population density.