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Concentraciones de sulfato y nitrato de un núcleo de hielo del sur de Groenlandia
Science (New York, N.Y.)
|May 23, 1986
Resumen
Los núcleos de hielo de Groenlandia revelan aumentos significativos en la contaminación por sulfatos y nitratos desde principios del siglo XX. Estos cambios en la deposición atmosférica están relacionados con las emisiones industriales de América del Norte y Eurasia.
Área de la Ciencia:
- Ciencias del medio ambiente Ciencias del medio ambiente.
- Glaciología glaciología.
- Química de la atmósfera La química de la atmósfera
Sus antecedentes:
- Los núcleos de hielo proporcionan un registro histórico de la composición atmosférica.
- Los niveles de contaminación pasados se pueden reconstruir mediante el análisis de especies químicas dentro de las capas de hielo.
Objetivo del estudio:
- Para analizar las concentraciones químicas en un núcleo de hielo del sur de Groenlandia que abarca 1869-1984.
- Para identificar tendencias en la deposición de sulfato y nitrato a lo largo del tiempo.
- Investigar las fuentes potenciales de los cambios químicos observados.
Principales métodos:
- Análisis de las concentraciones de isótopos de oxígeno, cloruro, nitrato y sulfato en un núcleo de hielo.
- La datación de las capas del núcleo de hielo para establecer una línea de tiempo desde 1869 hasta 1984.
Principales resultados:
- Las concentraciones de sulfato no sal de mar se han triplicado desde aproximadamente 1900-1910.
- Las concentraciones de nitrato se han duplicado desde aproximadamente 1955.
- Los aumentos observados se correlacionan con períodos de crecimiento industrial.
Conclusiones:
- La deposición atmosférica de sulfato y nitrato ha aumentado significativamente en Groenlandia.
- Las emisiones antropogénicas de América del Norte y Eurasia probablemente contribuyen a estas tendencias.
- Los datos de núcleos de hielo ofrecen información valiosa sobre los patrones de contaminación ambiental a largo plazo.
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