TEMPERATURE, HUMIDITY AND PRECIPITATION VARIATIONS IN ARGENTINA AND THE ADJACENT SUB-ANTARCTIC REGION DURING THE PRESENT CENTURY

The problem regarding a possible warming in Argentina and in the adjac ent sub-antarctic region has been studied within the framework of the global warming issue and taking into account the evolution of the glob al mean surface temperature since 1880. For this reason, the decadal a verages of the annual means of the maximum, minimum and daily mean tem perature, the vapor pressure and the precipitation corresponding to th e periods of 1941-1950 and 1981-1990 have been compared for representa tive meteorological stations. The decade of 1941-1950 was chosen as a reference one as it is the warmest decade of the period of 1901-1950 i n the Argentine Pampa and Chaco plains. Then, the annual mean temperat ure series and the annual precipitation series from representative sta tions of the Argentine geographical regions have been analysed. The re sults of these studies indicate a significant warming in southern Pata gonia and South Orkney Islands since the forties or earlier, with the augmentation of each of three temperature parameters being larger than 1 degrees C. North of about 42 degrees S, however, no warming has bee n observed. Here, mean extreme temperatures vary in opposite direction s: the mean maximum temperature decreases, while the mean minimum temp erature increases. This behavior is consistent with that of the vapor pressure and the precipitation which - north of 40 degrees S - have in creased since the forties. As to the sub-antarctic region in particula r, the augmentation of the precipitation observed in Base Orcadas stat ion (South Orkney Islands), which proved to be significant at the conf idence level of 1%, may be partially associated with the general warmi ng in that region.