Characterizatión of main external climate influences in rainfall and air temperature in the Paute River Basin - Southern Andes of Ecuador

Abstract

Characterization of climate variability in the Andes mountain range needs special assessment as rainfall and temperature are extremely variable in space and time. This paper examines the anomalies of observed month rainfall and temperature data of respectively 25 and 16 stations, from the early 1960‟s to the 1990‟s and compare them against anomalies from different external climate influences in annual and 3-month seasonal block periods. The stations are located in the Río Paute Basin in the Ecuador‟s southern Andes. All stations are within the elevation band 1800 and 4200 m a.s.l. and affected by the Tropical Pacific, Amazon and Tropical Atlantic climate. The results show similar temperature variations for the entire region, which are highly influenced by the ENSO, especially during the DJF season. During JJA, the correlation is weaker showing the influence of other climate factors. Higher temperature anomalies are found at the high elevation sites while in deep valleys the anomalies are less significant. Rainfall variations depend, in addition to elevation, on additional factors such as the aspect orientation, slope and hydrological regime. Highest and most significant rainfall anomalies are found in the eastern sites.