Located on the west margin of the Rio de la Plata estuary, the capital city of Buenos Aires is often affected by positive and negative storm surges due to strong southeasterly and northwesterly winds, respectively, which sweep the estuary. While positive surges cause severe flooding, negative surges affect navigation and drinking water supply. Since Buenos Aires is densely populated, a quantitative assessment of the variations in the regime of storm surges will help to develop policies for reducing their impacts. Changes in frequency, duration, and height of storm surges over the period 1905–2003 were determined from statistical analyses of hourly water levels. Calculations of the tidal constants used harmonic analyses of 19 y periods to account for any variation in the astronomical tide. Positive and negative surges were chosen from the residuals between observed levels and the predicted tide. The results show that the decadal averages of frequency and duration for positive surges have increased in the last three decades, but they have decreased for negative surges. The average decadal trends of the maximum positive and negative surges in each year, 1.46 ± 0.08 mm/y and 1.02 ± 0.09 mm/y, respectively, compare well with the relative mean water-level rise for Buenos Aires: 1.68 ± 0.05 mm/y. However, the height of positive surges has decreased in the last decade, and negative surges have become more intense in the last two decades.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 24 • No. sp1