Azad Sarita, Rajeevan M
Indian Institute of Technology Mandi, Mandi 75001 Himachal Pradesh, India.
Indian Institute of Tropical Meteorology, Dr Homi Bhabha Road, Pashan 411 008 Pune, India.
Sci Rep. 2016 Feb 3;6:20145. doi: 10.1038/srep20145.
EI Nino-Southern Oscillation (ENSO) and Indian monsoon rainfall are known to have an inverse relationship, which we have observed in the rainfall spectrum exhibiting a spectral dip in 3-5 y period band. It is well documented that El Nino events are known to be associated with deficit rainfall. Our analysis reveals that this spectral dip (3-5 y) is likely to shift to shorter periods (2.5-3 y) in future, suggesting a possible shift in the relationship between ENSO and monsoon rainfall. Spectral analysis of future climate projections by 20 Coupled Model Intercomparison project 5 (CMIP5) models are employed in order to corroborate our findings. Change in spectral dip speculates early occurrence of drought events in future due to multiple factors of global warming.
众所周知，厄尔尼诺 - 南方涛动（ENSO）与印度季风降雨呈反比关系，我们在降雨频谱中观察到在3 - 5年周期波段出现频谱低谷。有充分记录表明，厄尔尼诺事件与降雨不足有关。我们的分析表明，这种频谱低谷（3 - 5年）未来可能会向更短周期（2.5 - 3年）转变，这表明ENSO与季风降雨之间的关系可能会发生变化。为了证实我们的发现，我们采用了20个耦合模式比较计划第5阶段（CMIP5）模型对未来气候预测进行频谱分析。频谱低谷的变化推测由于全球变暖的多种因素，未来干旱事件可能会提前发生。
