Urban-biased trends in Buenos Aires' mean temperature

BARROS, VICENTE; CAMILLONI, INÉS

CLIMATE RESEARCH

INTER-RESEARCH

Lugar: Oldendorf/Luhe; Año: 1994 vol. 4 p. 33 - 45

0936-577X

The yearly mean temperature in northeastern Argentina is described by a simple model of geographic coordinates and elevation. According to the simulation tests, the mean temperature in a given year at any rural location can be estimated with a RMSE (root-mean-square error) of less than 0.5C as long as there are data from at least 8 stations in the region. The mean temperature for a 5 yr period can be estimated with an even lower RMSE of less than 0.4C. In spite of the severe limitations of the available data, use of the model permits Buenos Aires' urban-rural temperature differences since 1929 to be calculated. During the 1940s and 1950s the urban-rural temperature difference increased linearly, later slowing and reaching a maximum during the 1960s. The decrease in the urban-rural temperature difference after the 1960s could be attributed at least in part to the general warming of the region. An extension of the latter finding to global surface mean temperature suggests the possibility that the presumed global warming is now being masked to a certain extent by the urban heat island effect, contrary to what happened during the first 60 yr of the century.