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Cambios en las propiedades de la masa de agua del océano: ¿oscilaciones o tendencias?
Harry L Bryden1, Elaine L McDonagh, Brian A King
1Southampton Oceanography Centre, Empress Dock, Southampton SO14 3ZH, UK. h.bryden@soc.soton.ac.uk
Science (New York, N.Y.)
|June 28, 2003
Resumen
Las aguas en modo termoclina se han vuelto recientemente más saladas y frías, revirtiendo una tendencia de refrescamiento observada desde 1965 hasta 1987. Estos hallazgos revelan importantes oscilaciones naturales en las propiedades oceanográficas.
Área de la Ciencia:
- Oceanografía La oceanografía es la oceanografía.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- Las aguas en modo de termoclina son indicadores cruciales de los cambios oceanográficos.
- Las interpretaciones anteriores vinculaban las tendencias de refrescamiento con el cambio climático antropogénico.
Objetivo del estudio:
- Para analizar cambios a largo plazo en las propiedades del agua en modo de termoclina.
- Para comparar datos hidrográficos de varias décadas.
Principales métodos:
- Utilizó cinco secciones hidrográficas que abarcan desde 1936 hasta 2002.
- Se analizaron los datos de temperatura y salinidad de las aguas de la termoclina superior (10-17°C).
Principales resultados:
- Las aguas de modo mostraron pocos cambios entre 1936 y 1965.
- Se observó refrescamiento desde 1965 hasta 1987.
- Desde 1987, las aguas del modo se han vuelto significativamente más saladas y frías.
Conclusiones:
- Los cambios recientes en el modo de las aguas revierten en gran medida la tendencia de refrescamiento de 1965-1987.
- Las sustanciales oscilaciones naturales, no solo los factores antropogénicos, influyen en las propiedades del modo-agua.
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