Resumen

ALDAMA, Alvaro A.. Three-Part Descomposition of Natural Flows: Application to the Colorado River Drought Characterization. Tecnol. cienc. agua [online]. 2016, vol.7, n.5, pp.167-195. ISSN 2007-2422.

An analysis of the natural flow in the Colorado River basin is presented in this paper, within the context of what is established by the 1944 Treaty between Mexico and the United States. Firstly, the monthly record of natural annual flow at the station closest to the border between both countries, which corresponds to the location just upstream of the Imperial dam, is built. Thus, values between September of 1906 and December of 2012 were included, in accordance with the most recently available information. The most important statistics of such record are estimated and it is shown that the record itself does not follow a normal distribution. The 2.28, 15.87, 84.13 y 97.72 sample percentiles are computed and on the basis of their values, the historical record is characterized in terms of extremely scarce, scarce, normal, abundant and extremely abundant periods. The dominant periods in the record are identified via Fourier analysis. Through a novel three-part decomposition, the trend, dominant cyclical and random components of the record are identified. It is shown that the last follows a normal distribution and a characterization of the historical record in very dry, dry, normal, humid and very humid periods is performed, on the basis of a dynamic standardized runoff index, proposed by the author herein.

Palabras llave : Natural annual flow in the Colorado River basin; 1944 Treaty between México and the United States; transboundary waters; normal distribution; Central Limit Theorem; percentiles; spectral analysis; three-part decomposition; trend; cyclical component; random component; dynamic standardized runoff index.