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Nubes convectivas profundas con agua líquida superenfriada sostenida hasta -37,5 grados C
1Institute of Earth Sciences, the Hebrew University of Jerusalem, Israel. daniel@vms.huji.ac.il
Nature
|June 6, 2000
Resumen
Se encontró agua líquida altamente superenfriada, crucial para comprender los procesos de las nubes, en nubes convectivas profundas. Estos hallazgos revelan que el agua líquida persiste hasta -37.5°C, lo que afecta a los modelos meteorológicos y climáticos.
Área de la Ciencia:
- Ciencias de la atmósfera Ciencias atmosféricas.
- Física de las nubes Física de las nubes.
- Meteorología Meteorología.
Sus antecedentes:
- El agua altamente superenfriada (agua líquida por debajo de 0 °C) es conocida en cirros y nubes de onda, pero no está bien estudiada en nubes convectivas profundas.
- Los datos satelitales indican la ocurrencia frecuente de agua muy superenfriada en las tormentas convectivas continentales.
- Las investigaciones anteriores carecían de mediciones in situ para el agua súper enfriada en las cimas de nubes convectivas profundas.
Objetivo del estudio:
- Para reportar las mediciones in situ de agua altamente superenfriada en nubes convectivas profundas.
- Para cuantificar la cantidad y el tamaño de las gotas de agua líquida a temperaturas muy bajas.
- Proporcionar datos para mejorar las simulaciones de procesos en la nube y comprender las implicaciones climáticas.
Principales métodos:
- Mediciones in situ utilizando instrumentos de aeronaves dentro de nubes convectivas profundas.
- Análisis del contenido de agua condensada y distribución del tamaño de las gotas a temperaturas bajo cero.
- Observación de la transición de fase de líquido a hielo para inferir los mecanismos de congelación.
Principales resultados:
- La mayor parte del agua condensada en las nubes convectivas profundas se mantuvo líquida hasta -37.5°C.
- El contenido de agua líquida alcanzó 1,8 g m-3, un orden de magnitud más alto que el reportado anteriormente.
- El diámetro medio del volumen de las gotas fue de 17 micrómetros.
- El hielo se observó exclusivamente a temperaturas ligeramente más frías, lo que sugiere una congelación homogénea.
Conclusiones:
- Las nubes convectivas profundas pueden contener cantidades significativas de agua líquida altamente superenfriada.
- Estos hallazgos desafían las suposiciones existentes sobre los procesos de nube de fases mixtas.
- Los datos son vitales para mejorar la predicción numérica del tiempo y los modelos climáticos, particularmente con respecto a las precipitaciones, el granizo y la electrificación.
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