Influência da coluna total de ozônio na variabilidade da radiação ultravioleta sobre o sul da América do Sul

Abstract

Ozone (O3) is much less than 1% of the gases in the Earth's atmosphere; however, it is essential to life on Earth, because it absorbs ultraviolet radiation of the type B (UVB), which is harmful to the health of living beings. The tropical region is the largest producer of stratospheric ozone; however, due to the Brewer-Dobson circulation, this region has low values of ozone total column, which can be extended to higher latitudes. The overall goal of this study is to investigate the influence of the Ozone Total Column (CTO) depletion on the variability of the solar Ultraviolet Radiation (UVR) on the south of South America in the period from December 2004 to November 2014, using daily data of UVR and CTO depletion from the sensor Ozone Monitoring Instrument (OMI) from NASA. The relationship between the variables of the global ozone column and the Ultraviolet Index (I-UV) did not show any specific characteristics both meridional and seasonally, showing no influence / dependence between the variables, when the linear correlation coefficient presented values close to 0,5 (50%). The first pattern of PC (Principal component) showed that the months that have strong direct correlation occur in the quarters June-July-August (JJA) and September-October-November (SON). The linear regression showed a greater dependence from the influence of the CTO in UVR in the quarter December-January- February (DJF) reaching values higher than 0,8. In the year 2005 the anomalies were standardized in DJF and March-April-May (MAM) positive values reaching up to 3,0 standard deviations in the southern region of Brazil. The cases of significant depletion of the CTO layer have proven that only low levels of ozone are not determinant for the high values of UVR. The presence of bands of cloudiness was a possible factor for non-registration of high values of UVR. It was observed that both monthly and seasonally the P95 of ultraviolet radiation has higher values in the warmer months than in the colder months.