Agroclimatic Characterization of the Tropical Zone of Mexico

Mexico is considered a country with a predominantly tropical climate, since most of the country is generally located at 23°27'' north latitude, as part of the Tropic of Cancer. However, within this latitude there are temperate and semi-arid zones. The problem being faced is that the definition of tropics has been based just on Latitude, frequently ignoring the Altitude factor The above mentioned problem has led to an incomplete understanding of the real surface of the Mexican tropic and other methods employed in other countries are not applicable to the Mexican conditions. This work aimed to adequately delimit the tropical zone of the country in order to carry out programs able to trigger a sustainable development of both humid and subhumid tropics. The method was based on a detailed analysis of the physical environment. To process and determine the area covered by the tropical zone, the QGIS 3.22 Batioweiza software and the following databases were used: The digital elevation model from the National Institute of Statistic, Geography and Information (INEGI) with altitude values every 3 arc seconds (approximately a 90 × 90 m grid or 0.81 ha), climate database of the climatological normal of the National Meteorological System for the states of the Mexican Republic and the 1:250,000 scale map soils from the World Reference Base or WRB for its acronym in English. Two of the variables that determine the tropical climate are the temperature, which must be higher than 18°C, and the average annual rainfall, higher than 600 mm. The images were reclassified according to altitude conditions, average annual temperature, average annual rainfall, soils, and agricultural and livestock areas. The regionalization of the tropical zone determined a total area of 70 million hectares, 18% (12.6 million has) considered as humid and most of the area 82% (57.4 million has) as sub-humid or dry tropics.