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Variabilidad interanual del metano atmosférico: posibles efectos de la oscilación El Niño-Sur
Science (New York, N.Y.)
|April 4, 1986
Resumen
Los niveles de metano en la atmósfera de la Tierra muestran ciclos estacionales y variaciones interanuales. Un importante evento de El Niño causó que las concentraciones de metano cayeran por debajo de los niveles esperados, lo que ralentizó la tasa de aumento a largo plazo.
Área de la Ciencia:
- Ciencias de la atmósfera Ciencias atmosféricas.
- Ciencias del clima Ciencias del clima Ciencias del clima
- Monitoreo del medio ambiente El monitoreo del medio ambiente.
Sus antecedentes:
- El metano es un gas de efecto invernadero significativo con un ciclo de vida atmosférico complejo.
- Comprender las tendencias de concentración de metano es crucial para la investigación del cambio climático.
- Se observan variaciones estacionales e interanuales en los niveles de metano, pero no se comprenden completamente.
Objetivo del estudio:
- Para analizar a largo plazo los datos de concentración de metano de mediciones continuas.
- Para identificar y caracterizar la variabilidad estacional e interanual en el metano atmosférico.
- Para evaluar el impacto de los principales eventos climáticos, como El Niño-Oscilación Sur, en las tendencias del metano.
Principales métodos:
- Las mediciones atmosféricas continuas de las concentraciones de metano se llevaron a cabo en Cape Meares, Oregon.
- Análisis de datos durante un período de 6 años para identificar tendencias y variaciones cíclicas.
- Análisis de correlación para vincular la variabilidad del metano con fenómenos climáticos como El Niño y la Oscilación del Sur.
Principales resultados:
- Las concentraciones de metano muestran claros ciclos estacionales.
- La tasa de aumento del metano muestra variaciones interanuales significativas.
- Se observó una disminución prominente en la concentración de metano por debajo de los niveles esperados durante el último evento importante de El Niño-Oscilación Sur.
Conclusiones:
- La variabilidad interanual, influenciada por eventos como El Niño, impacta las tasas de acumulación de metano a largo plazo.
- La tasa a largo plazo de aumento del metano en Cabo Meares es de aproximadamente 16 partes por mil millones en volumen por año (1% anual).
- Esta tasa observada es menor de lo estimado inicialmente a partir de cálculos anteriores a corto plazo, lo que pone de relieve la importancia de un monitoreo extendido.
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