近年研究強調大氣雲輻射效應（atmospheric cloud-radiative effect, ACRE）對Madden-Julian Oscillation（MJO）成長與維持的重要性。然而，MJO 的雲輻射效應將如何隨著溫室氣體增加而變化，其相關機制仍須更多討論。為此，我們採用Geophysical Fluid Dynamics Laboratory′s CM4.0 (GFDL-CM4) physical climate model討論MJO在1%CO2情境下的變化。與前人研究一致，全球暖化下MJO有較強的對流活動，其雲的發展也更顯著。增強的greenhouse enhancement factor (GEF) 和增多的高雲族覆蓋結果一致。MJO的雲輻射效應與中層垂直水氣平流有良好的相關性，其主要貢獻來自於氣候平均（background）水氣垂直梯度和季內尺度垂直運動的交互作用。這個關聯性顯示雲輻射效應的增強，是因為在暖化下有更多水氣被輸送至較高的對流層。研究結果也指出，降低的有效粗濕穩定度（effective gross moist stability）是由於增強的垂直水氣平流與雲輻射效應，這些結果強調大氣—雲—輻射效應在暖化後對MJO的重要性。;Recent research has shown that the atmospheric cloud-radiative effect (ACRE) plays a key role in the growth and maintenance of the Madden-Julian Oscillation (MJO). However, the mechanisms in how the ACRE in the MJO will change with increasing greenhouse gases are still not well understood. To this end, the Geophysical Fluid Dynamics Laboratory′s CM4.0 physical climate model (GFDL-CM4) is employed to elucidate changes in the MJO with 1% increases in CO2 concentration per year. Under global warming, the MJO amplifies and the evolution of the cloud population becomes more pronounced, consistent with previous studies. An intensification of the greenhouse enhancement factor (GEF) is found, in agreement with an increase in high clouds. The ACRE exhibits a high correlation with the mid-level vertical moisture advection, which is dominated by the interaction between mean-state moisture and the intraseasonal vertical velocity. This relation implies that ACRE strengthens because more moisture is transported to the upper troposphere with warming. Results also indicate that the effective gross moist stability (GMS) decreases due to the strong vertical moisture advection and increased radiative effects from ACRE. According to GFDL-CM4, these findings suggest that moisture-cloud-radiation interactions may become more important to the MJO in a warmer climate.
