Paleclimatic Events Of El Ninos, La Niñas And Neutrals And Of Precipitation In Southern Ans Eastern Of Amazônia

Abstract

Climatic studies associated with the physical variables of the atmosphere to identify patterns and their variations require long data series to have more reliable results. These series with instrumental measures do not always have this longevity of observations, so approximations using paleoclimatic techniques are important to infer variability related to these physical processes in nature. Variations on the sea surface temperature (SST) that cause pressure differences on the surface between the west and east of the Pacific Ocean, called the South Oscillation, are characteristics that are associated with events of SST changes in the Tropical Pacific (El Ninõs , La Niñas and Neutros), which climatically impact various areas of the globe. Proxies of precipitation were used for the areas in the west and east of the Pacific, 50-1955 DC, the South Oscillation Index and the precipitation of two areas in the southwest (1800-2012 DC) and east (1800-2012 DC) of the Amazon. The base methodology was the calculation of Z scores used as measures of variability of the proxies. The main results showed that the IOS proxies indicated El Niños (La Niñas) events associated with periods of warmer global climates in the RWP and MWP period and colder in the DACP and LIA period. For the southwest and eastern areas of the Amazon, the proxies showed that there was a major variation in precipitation over the past 200 years in the southwest sector of the same.

Keywords:
ENSO; SOI; climatic variation