Low-frequency oscillations in radiative-convective models
Although eastward propagation is usually regarded as an essential feature of the low-frequency ``Madden-Julian oscillation`` observed in the tropical atmosphere, many observations indicate that there is an important stationary or quasi-stationary component of the oscillation. Yasunari (1979), for example, investigated the stationary 30--60 day variation in upper tropospheric cloudiness in the Asian summer monsoon region. In a case study of the 30--60 day oscillation. Hsu et al. (1990) found a strong stationary oscillation of the divergence, outgoing longwave mdiadon and other fields. A recent observational study by Weickmann and Khalsa (1990) offers further evidence that the Madden-Julian oscillation has an important stationary component. In this paper, we present evidence that intraseasonal oscillations can be produced by local radiative and convective processes. This suggests that the observed propagating Madden-Julian wave is produced by interactions between these local processes and the large scale motion field, and is not essential for the existence of the observed oscillation.
- Research Organization:
- Colorado State Univ., Fort Collins, CO (United States). Dept. of Atmospheric Science
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG02-89ER69027
- OSTI ID:
- 10170891
- Report Number(s):
- CONF-9110161-6; ON: DE92018779; CNN: Grant NAG-5-1058
- Resource Relation:
- Conference: 5. American Meteorological Society (AMS) conference on climate variations,Denver, CO (United States),14-18 Oct 1991; Other Information: PBD: [1991]
- Country of Publication:
- United States
- Language:
- English
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