Semestral Journal of Centro Argentino de Meteorólogos, which is published  since 1970 and serves on the Core of Argentine Scientific Journals since 2005. Meteorologica publishes original papers in the field of atmospheric sciences and oceanography.

Registration number of intellectual property: RL-2018-42420861-APN-DNDA#MJ

ISSN 1850-468X

Volume 40 – N°1 MORE NOTES FROM THIS ISSUE

EXPLORING MAXIMUM AND MINIMUM TEMPERATURES IN DIFFERENT REANALYSIS. PART 2: VARIABILITY IN DIFFERENT TIME SCALES

Pablo Gabriel Zaninelli, Claudio Guillermo Menéndez y Andrea Fabiana Carril

Centro de Investigaciones del Mar y la Atmósfera (CIMA), CONICET-UBA, Buenos Aires, Argentina
Departamento de Ciencias de la Atmósfera y los Océanos (DCAO), FCEN, Universidad de Buenos Aires, Argentina
UMI IFAECI/CNRS, Buenos Aires, Argentina

Manuscript received on 28 August 2013, in final form on 1 July 2014

ABSTRACT

In this work it is analyzed the maximum temperature (TX) and minimum temperature (TN) variability for summer and winter, respectively, in southeastern South America (SESA) in the period 1961-2000 using an observational climatology and three multidecadal reanalysis (NCEP, ERA40, 20CR). It is also described the changes between the 20-year periods 1981-2000 and 1961-1980 in daily and interannual variability and in extremes (percentiles 75 and 25) of TX and TN. The geographical patterns of change between both periods of the daily variability of TX and TN are similar to the geographical patterns of changes in extremes of these variables. In Argentina, in general, there is a decrease in the frequency of hot summer days and cold winter nights in agreement with a decrease of daily variability. The maximum interannual variability of TX happens in a transitional zone which includes much of central and northern Argentina, where soil moisture constrains evapotranspiration variability and thus resulting feedbacks with the atmosphere. The changes between both periods in the observational climatology suggest a shift to the southwest in the zone of maximum interannual variability of TX possibly associated with changes in the variability of precipitation. Overall reanalysis have difficulty reproducing the main geographical patterns of changes in daily and interannual variability of TX and TN between the two periods.

Keywords: reanalysis intercomparison, maximum temperature, minimum temperature, climate variability