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La formación de hielo cúbico en condiciones relevantes para la atmósfera de la Tierra
Benjamin J Murray1, Daniel A Knopf, Allan K Bertram
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.
Nature
|March 11, 2005
Resumen
Los experimentos de laboratorio muestran que el hielo cúbico se forma en gotas de agua pura que se congelan por debajo de 190 K. Este hallazgo es crucial para comprender las nubes de hielo atmosférico y su impacto potencial en el clima de la Tierra.
Área de la Ciencia:
- Química de la atmósfera La química de la atmósfera
- La cristalografía es una técnica de cristalografía.
- La geofísica es la geofísica.
Sus antecedentes:
- La nucleación homogénea de hielo en las gotas de agua atmosféricas suele formar hielo hexagonal.
- Informes anteriores sugieren la posibilidad de la formación de hielo cúbico en la atmósfera de la Tierra.
Objetivo del estudio:
- Para investigar la formación de hielo cúbico en agua pura y gotas de solución acuosa en condiciones atmosféricas.
- Para determinar el rango de temperatura y las condiciones que favorecen la formación de hielo cúbico.
Principales métodos:
- Experimentos de laboratorio que implican la nucleación homogénea de gotas de agua de tamaño micrométrico.
- Tasas de enfriamiento controladas que imitan las condiciones atmosféricas.
- Análisis de la formación de la fase de los cristales de hielo.
Principales resultados:
- Se observó la formación de hielo cúbico en agua pura y gotas de solución acuosa que se congelaban homogéneamente.
- La formación de hielo cúbico es dominante a temperaturas por debajo de 190 K.
- Este rango de temperatura es relevante para las nubes estratosféricas polares y las nubes tropicales de la tropopausa.
Conclusiones:
- El hielo cúbico puede formarse en la atmósfera de la Tierra bajo condiciones específicas.
- La presencia de hielo cúbico podría alterar la microfísica de las nubes, la presión del vapor de agua y las distribuciones de tamaño de las partículas de hielo.
- Esto puede conducir a una mayor deshidratación en la región de la tropopausa.
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