We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Diverse MJO Genesis and Predictability.
- Authors
Yuntao Wei; Hong-Li Ren; Baoqiang Xiang; Yan Wang; Jie Wu; Shuguang Wang
- Abstract
The Madden–Julian oscillation (MJO) is the dominant intra seasonal wave phenomenon influencing extreme weather and climate worldwide. Realistic simulations and accurate predictions of MJO genesis are the cornerstones for successfully monitoring, forecasting, and managing meteorological disasters 3–4 weeks in advance. Nevertheless, the genesis processes and emerging precursor signals of an eastward-propagating MJO event remain largely uncertain. Here, we find that the MJO genesis processes observed in the past four decades exhibit remarkable diversity with different seasonality and can be classified objectively into four types, namely, a novel downstream origin from the westward-propagating intra seasonal oscillation (WPISO; 20.4%), localized breeding from the Indian Ocean suppressed convection (IOSC; 15.4%), an upstream succession of the preceding weakly dispersive (WD; 25.9%), and strongly dispersive (SD; 38.3%) MJO. These four types are associated with different oceanic background states, characterized by central Pacific cooling, southern Maritime Continent warming, eastern Pacific cooling, and central Pacific warming for the WPISO, IOSC, WD, and SD types, respectively. The SD type is also favored during the easterly phase of the stratospheric quasi-biennial oscillation. Diverse convective initiations possibly imply various kinds of propagations of MJO. The sub seasonal reforecasts indicate robustly distinct prediction skills for the diverse MJO genesis. A window of opportunity for skillful week 3–4 prediction probably opens with the aid of the WPISO-type MJO precursor, which has increased the predictability of primary MJO onset by 1 week. These findings suggest that the diversified MJO genesis can be skillfully foreseen by monitoring unique precursor signals and can also serve as benchmarks for evaluating contemporary models’ modeling and predicting capabilities.
- Subjects
QUASI-biennial oscillation (Meteorology); EXTREME weather; MADDEN-Julian oscillation; OCEAN convection; CLIMATE extremes; OCEAN temperature
- Publication
Bulletin of the American Meteorological Society, 2023, Vol 104, Issue 4, pE792
- ISSN
0003-0007
- Publication type
Article
- DOI
10.1175/BAMS-D-22-0101.1