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La transición de la fase de percolación en el hielo marino
1K. M. Golden, Department of Mathematics, University of Utah, Salt Lake City, UT 84112, USA. S. F. Ackley, U.S. Army Cold Regions Research and Engineering Laboratory, Hanover, NH 03755, USA. V. I. Lytle, Antarctic Cooperative Research Centre a.
Science (New York, N.Y.)
|December 18, 1998
Resumen
El hielo marino se vuelve permeable al flujo de fluidos a una temperatura crítica, permitiendo el transporte de calor y nutrientes. Esta transición, explicada por la teoría de la percolación, es vital para comprender la geofísica y la biología del hielo marino.
Área de la Ciencia:
- La geofísica es la geofísica.
- Oceanografía La oceanografía es la oceanografía.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El hielo marino exhibe un cambio significativo en las propiedades de transporte de fluidos.
- Esta transición ocurre a una fracción de volumen de salmuera crítica (pc ≈ 5%) o a una temperatura (Tc ≈ -5°C).
- Por encima de Tc, el movimiento de la salmuera facilita la transferencia de calor y nutrientes; por debajo de Tc, el hielo marino se vuelve impermeable.
Objetivo del estudio:
- Para explicar el comportamiento crítico de las propiedades de transporte en el hielo marino.
- Para investigar el papel de los canales de salmuera en el hielo marino.
- Aplicar la teoría de la percolación para comprender la permeabilidad del hielo marino.
Principales métodos:
- Utilizando la teoría de la percolación para modelar el transporte del hielo marino.
- Comparando la microestructura del hielo marino con los polvos comprimidos.
- Predecir teóricamente la fracción crítica de volumen de salmuera (pc).
Principales resultados:
- Se identificó una fracción crítica de volumen de salmuera (PC) de aproximadamente el 5%.
- Se determinó una temperatura crítica (Tc) de aproximadamente -5°C para una salinidad de 5 partes por mil.
- La microestructura del hielo marino muestra similitudes con los polvos comprimidos, lo que respalda las predicciones teóricas.
Conclusiones:
- La transición en el transporte de fluidos de hielo marino se rige por la teoría de la percolación.
- Comprender esta transición crítica es crucial para la geofísica, la biología y la teledetección del hielo marino.
- Las predicciones teóricas de pc se alinean con las propiedades observadas del hielo marino.
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