Other airmass types include arctic, equatorial, and monsoon. Fronts are the boundaries between air masses of different temperature. Extratropical cyclones (low pressure areas) also form along these fronts and draw their energy from the temperature difference between air masses. On average, warm air masses tend to flow poleward, and cold air masses tend to flow equatorward, helping to cool the tropics and warm the polar regions.
Aztec Farming. 1  Aztec Farming and Agriculture: Chinampas System. 2  Aztec Farming and Agriculture: Chinampas Construction. 3  Aztec Farming and Agriculture: Farm Land Ownership Rules. 4  Aztec Farming and Agriculture: Farm Crops Grown. 5  Aztec Farming and Agriculture: Aztec Farmers. 6  Aztec Farming and Agriculture: Farming Tools. Aztecs used relatively primitive tools for Aztec farming and agriculture. They did not have advanced tools for the time such as plows. The most important tool for Aztec farming and agriculture was the classic wooden digging stick. This stick was called Uictli in the Nahuatl language. There were multiple types of these digging sticks and other than farming, it was often also used for other purposes such as construction and repair work.
But by far their most sophisticated use of mathematics was in astronomy. Much of knowledge of Aztec astronomy has been lost, but the there's a good synthesis of the surviving information in the book Skywatchers by Anthony Aveni. Following the Maya, the Aztecs had good calculations of the movements of many of the classical planets. For example, they calculated the cycle of Venus at 584 days (the time it takes Venus to overtake earth in its orbit.)