Seasonal analysis of the urban heat island at Buenos Aires city

BARRUCAND, MARIANA; CAMILLONI, INÉS

Melbourne

Conferencia; 9th International Conference on Southern Hemisphere Meteorology & Oceanography; 2009

American Meteorological Society

The Buenos Aires urban heat island (UHI) effect is analyzed for this city, considering both annual and seasonal characteristics. The largest intensities are found for the nocturnal UHI (03 and 21 LT) and an “inverse” effect (the city cooler than the rural surrounding) with absolute intensities lower than 0.5°C is found during the afternoon (15 LT) for some years. Although the Metropolitan Area population had a persistent increase since the beginning of the 20 century, the UHI effect has been decreasing in the studied period (1960-2007), especially at nocturnal hours for all seasons. These results could be related with a diminution of clear skies and calm frequencies in Buenos Aires. The wind speed analysis does not present the expected inverse relationship with the UHI intensity, suggesting that the radiative processes involved for the Buenos Aires UHI development are dominant over the dynamical ones.