Variability analysis of the troposphere and low-stratosphere in the Southern Hemisphere

In the 20’s, researchers such as Dobson et al. pointed out the relationship between the troposphere and stratosphere, though this line of research was left. In the 80’s the finding of the ozone-layer deplation over the Antartic led the researchers to study distinct features of the stratosphere. Nowadays, one can count on stratospheric data records long enough that have permitted to performe climatic studies which confirm the relationship between the troposphere and the stratosphere.

The Analysis of 70 hPa-temperature anomalies for the period 1979-97 in the Southern Hemisphere, by means of Principal Components, showed the impact of both the Chichon and the Monte Pinatibo volcanic eruptions on the tropical and subtropical regions, also the clear evidence of ocurrence of the ENSO event as well as negative trends in the Antartic-region time-series.

These evidences have led us to study the geopotential heigths of 1000, 500 and 70 hPa corresponding to the period 1979-97 through the use of the Principal Components Analysis in order to estimate the inter-monthly-to-inter-annual variability by employing data from the NCEP re-analysis. For so, the annual cylce is filterd out so as to eliminate the seasonality in base on the refence period 1982-91 and thus the mean-monthly anomaly fields are obtained.