Pan evaporation analysis in central Mxico: Trends, self-affinity and important frequencies

International Journal of Physical Sciences

Fidel Blanco-Macias¹ 

关键词: Linear trends;    fractal dimension;    power spectrum density;    yearly cycle;    quasi–    biannual cycle;    El Niñ;    o Southern Oscillation;    sunspot cycle.;   

DOI  :  10.5897/IJPS10.586

学科分类：物理（综合）

来源: Academic Journals

【 摘 要 】

Long-term monthly pan evaporation time series registered at 40 meteorological stations located within Mexico’s state of Zacatecas were analyzed in order to identify their trends. In addition, we analyzed the power spectrum signals of evaporation anomaly series in order to identify their important frequencies and its possible connection with periodic phenomena. Results suggest that negative trends are prevailing over positive trends. We found negative linear trend for 27 out of 40 pan evaporation time series; 18 of the 27 decreasing trends were significant at p<0.05. On the other hand, 13 out of 40 pan evaporation trends were positive but only 3 at significant level (p<0.05). Moreover, noise in all of these monthly pan evaporation series tends to be a persistent behavior. Additionally, we found that important frequencies could be related with the yearly cycle, quasi–biannual cycle, ‘El Niño Southern Oscillation’ phenomena and sunspot cycle.

【 授权许可】

CC BY