Relation of El Nino and La Nina phenomena to precipitation, evapotranspiration and temperature in the Amazon basin.
Weather phenomena El Nino and La Nina are observed by meteorological variables, which allows you to track climate change and its possible effects in certain regions. The objective of this study was to analyze the behavior of rainfall, temperature and evapotranspiration in the Amazon river basin (Latitudes 5deg N to 20deg S and Longitudes 50deg W to 80deg W) comparing them with the occurrence of El Nino and La Nina phenomena, from January 2000 to December 2016. The values referring to the meteorological variables were obtained from the TRMM and MODIS orbital sensors. After data pre processing, the data were separated into monthly and annual scales and per period according to the presence or absence of El Nino and La Nina phenomena. Based on the results obtained, it was observed that the studied variables were affected by modification of both phenomena. The modifications are more noticeable in the distinction between the more and less rainy periods. Among the variables studied, the evapotranspiration was severely affected in the rainiest months, the La Nina phenomenon, and the least rainy months, El Nino. Thus, it was possible to conclude that, in general, the presence of La Nina increased precipitation values in comparison to the Neutral period, but the inverse occurs in the presence of El Nino. The methodology applied in the present study was adequate for the analysis of the modifications of the meteorological variables coming from the El Nino and La Nina phenomena, being able to be adapted to other variables and regions.
The Science of the total environment