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Dilución del norte del Océano Atlántico Norte en las últimas décadas
Ruth Curry1, Cecilie Mauritzen
1Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA 02543, USA. rcurry@whoi.edu
Science (New York, N.Y.)
|June 18, 2005
Resumen
Las grandes adiciones de agua dulce al Océano Atlántico Norte desde la década de 1960 están refrescando áreas clave. Esta importante afluencia de agua dulce puede impactar en la circulación meridional del Atlántico durante el próximo siglo.
Área de la Ciencia:
- Oceanografía La oceanografía es la oceanografía.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
- Hidrología Hidrología Hidrología.
Sus antecedentes:
- La salinidad del océano es un indicador clave del flujo de agua dulce.
- El Océano Atlántico Norte juega un papel crítico en los patrones de circulación oceánica global.
Objetivo del estudio:
- Para cuantificar la cantidad y el momento de la entrada de agua dulce en los mares nórdicos y las cuencas subpolares.
- Evaluar el impacto potencial del refrescamiento observado en la circulación de volcado meridional del Atlántico.
Principales métodos:
- Análisis de los datos históricos de salinidad desde mediados de la década de 1960 hasta mediados de la década de 1990.
- Estimación del volumen de agua dulce y las tasas de entrada basadas en los cambios de salinidad.
Principales resultados:
- Se estima que 19.000 +/- 5000 kilómetros cúbicos de agua dulce adicional entraron en los mares nórdicos y las cuencas subpolares entre 1965 y 1995.
- Aproximadamente 10.000 kilómetros cúbicos de esta agua dulce entraron a finales de la década de 1960 a un ritmo de 2000 kilómetros cúbicos por año.
- La acumulación de agua dulce observada sugiere una escala de tiempo de un siglo para alcanzar los umbrales críticos de refrescamiento.
Conclusiones:
- Se ha producido un importante refrescamiento en el norte del Atlántico Norte desde mediados del siglo XX.
- La tasa de entrada de agua dulce, particularmente a fines de la década de 1960, fue sustancial.
- Estos cambios pueden tener implicaciones a largo plazo para la estabilidad de la circulación de volteo meridional del Atlántico.
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