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The location of the Intertropical Convergence Zone (ITCZ) can be established as a function of convergence between tropical trade winds from the Northern and Southern Hemispheres. This zone has a great impact on the weather since it directly affects the distribution of precipitation in equatorial and tropical regions on a global scale. This document elaborates on the development of a methodology to locate the ITCZ using a convergence algorithm in the vector field of wind velocity obtained from the ERA Interim reanalysis model. This methodology is unique because it relies on a robust concept of gradient analysis and achieves a location range for ITCZ in defined periods of time registered historically, which has not been developed in previous studies. The methodology consists of a series of individual algorithms that allow for the cleaning, segmentation, and debugging of convergence data, until simplified maps for visualization are obtained using MATLAB®. The results are statistical ranges of the location of the ITCZ in each month of the 41 years of data available, meridional shift patterns, and contrast maps between cumulative monthly location and the location on months of years where El Niño Southern Oscillation (ENSO) was present to show possible correlation.
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