The objective of this article was to design and implement a system that allows evaluating the variation of the area of a lagoon and a snow-capped mountain in Ecuador through satellite image processing, the Yahuarcocha lagoon and the Cotopaxi volcano were selected due to the availability of many satellite images without distortions. The images downloaded from the Landsat-7 and Landsat-8 satellite were obtained from the Earth Explorer platform, considering that the Landsat-7 satellite images had to go through a Pre-processing to improve their quality due to the failure of the Scan Line Corrector (SLC), ArcGIS software was used for this. Subsequently, with MATLAB software, the system that executes the Processing of the images was carried out, which consisted of making a cutout of the area of interest, generating a mask to have a more specific area, applying the thresholding, calculating the area that each image has and finally display the results on a two-dimensional graph. Obtaining as a result that the values generated by the system are valid and reliable, since the validation was carried out with 8 water resources, between lagoons and snow-capped mountains with hypothetical values, through inferential statistics with the T Student test for a sample in the which the null hypothesis was accepted in all cases. Additionally, a mathematical prediction model for the year 2022 was carried out using a polynomial of degree 1. Future research should try to validate the mathematical prediction models obtained in this article.